draft-ietf-mmusic-sdp-atm-01.txt   draft-ietf-mmusic-sdp-atm-02.txt 
Internet Engineering Task Force Internet Engineering Task Force
Internet Draft Rajesh Kumar Internet Draft Rajesh Kumar
Document: draft-ietf-mmusic-sdp-atm-01.txt Mohamed Mostafa Document: draft-ietf-mmusic-sdp-atm-02.txt Mohamed Mostafa
October 1, 2000 Cisco Systems October 27, 2000 Cisco Systems
Expires: April 1, 2001 Expires: April 27, 2001
Conventions for the use of the Session Description Protocol (SDP) Conventions for the use of the Session Description Protocol (SDP)
for ATM Bearer Connections for ATM Bearer Connections
STATUS OF THIS DOCUMENT STATUS OF THIS DOCUMENT
This document is an Internet-Draft and is in full conformance with This document is an Internet-Draft and is in full conformance with
all provisions of Section 10 of RFC2026. all provisions of Section 10 of RFC2026.
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
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addressed are Type 1, Type 2 and Type 5. This list of conventions is addressed are Type 1, Type 2 and Type 5. This list of conventions is
meant to be exhaustive. Individual applications can use subsets of meant to be exhaustive. Individual applications can use subsets of
these conventions. Further, these conventions are meant to comply these conventions. Further, these conventions are meant to comply
strictly with the SDP syntax as defined in rfc2327. strictly with the SDP syntax as defined in rfc2327.
1. Introduction...............................................................2 1. Introduction...............................................................2
2. Representation of Certain Fields within SDP description lines..............4 2. Representation of Certain Fields within SDP description lines..............4
2.2 Representation of Parameter Values.....................................4 2.2 Representation of Parameter Values.....................................4
2.3 Directionality Convention..............................................4 2.3 Directionality Convention..............................................4
2.4 Case convention.........................................................5 2.4 Case convention.........................................................5
3. Capabilities Provided by SDP conventions..................................5 2.5 Use of special characters in SDP parameter values.......................5
4. Format of the ATM Session Description......................................6 3. Capabilities Provided by SDP conventions..................................6
4. Format of the ATM Session Description......................................7
5.1 The Origin Line.........................................................8 5.1 The Origin Line.........................................................8
5.2 The Session Name Line...................................................8 5.2 The Session Name Line...................................................9
5.3 The Connection Information Line.........................................9 5.3 The Connection Information Line.........................................9
5.4 The Timestamp Line.....................................................10 5.4 The Timestamp Line.....................................................11
5.5 Media Information Line for ATM connections.............................10 5.5 Media Information Line for ATM connections.............................11
5.5.1 The Virtual Connection ID.........................................11 5.5.1 The Virtual Connection ID.........................................12
5.5.2 The Transport Parameter...........................................13 5.5.2 The Transport Parameter...........................................14
5.5.3 The Format List for AAL1 and AAL5 applications....................14 5.5.3 The Format List for AAL1 and AAL5 applications....................15
5.5.4 The Format List for AAL2 applications.............................14 5.5.4 The Format List for AAL2 applications.............................15
5.5.5 Media information line construction...............................14
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5.6 The Media Attribute Lines..............................................17 5.5.5 Media information line construction...............................16
5.6.1 The 'atmmap' attribute.......................................20 5.6 The Media Attribute Lines..............................................18
5.6.2 The 'eecid' attribute............................................23 5.6.1 The 'atmmap' attribute.......................................21
5.6.3 The 'aalType' attribute............................................24 5.6.2 The 'eecid' attribute............................................25
5.6.4 The 'silenceSupp' attribute........................................24 5.6.3 The 'aalType' attribute............................................26
5.6.5 The 'ecanf' and 'ecanb' attributes.................................25 5.6.4 The 'silenceSupp' attribute........................................26
5.6.6 The 'gcf' and 'gcb' attributes.....................................26 5.6.5 The 'ecanf' and 'ecanb' attributes.................................27
5.6.7 The 'profileDesc' attribute........................................27 5.6.6 The 'gcf' and 'gcb' attributes.....................................28
5.6.8 The 'vsel' attribute...............................................28 5.6.7 The 'profileDesc' attribute........................................29
5.6.9 The 'dsel' attribute...............................................29 5.6.8 The 'vsel' attribute...............................................30
5.6.10 The 'fsel' attribute..............................................30 5.6.9 The 'dsel' attribute...............................................31
5.6.11 The 'capability' attribute.......................................31 5.6.10 The 'fsel' attribute..............................................32
5.6.12 The 'qosClass' attribute.........................................32 5.6.11 The 'capability' attribute.......................................33
5.6.13 The 'bcob' attribute.............................................32 5.6.12 The 'qosClass' attribute.........................................34
5.6.14 The 'stc' attribute..............................................32 5.6.13 The 'bcob' attribute.............................................34
5.6.15 The 'upcc' attribute.............................................33 5.6.14 The 'stc' attribute..............................................35
5.6.16 The 'atmQOSfparms' and 'atmQOSbparms' attributes..................33 5.6.15 The 'upcc' attribute.............................................35
5.6.17 The 'aal2QOSfparms' and 'aal2QOSbparms' attributes...............34 5.6.16 The 'atmQOSfparms' and 'atmQOSbparms' attributes..................35
5.6.18 The 'atmFtrfcDesc' and 'atmBtrfcDesc' attributes..................34 5.6.17 The 'aal2QOSfparms' and 'aal2QOSbparms' attributes...............36
5.6.19 The 'aal2FtrfcDesc' and 'aal2BtrfcDesc' attributes...............36 5.6.18 The 'atmFtrfcDesc' and 'atmBtrfcDesc' attributes..................36
5.6.20 The 'abrFparms' and 'abrBparms' attributes.......................36 5.6.19 The 'aal2FtrfcDesc' and 'aal2BtrfcDesc' attributes...............38
5.6.21 The 'clkrec' attribute............................................37 5.6.20 The 'abrFparms' and 'abrBparms' attributes.......................38
5.6.23 The 'prtfl' attribute.............................................37 5.6.21 The 'clkrec' attribute............................................39
5.6.24 The 'bearerType' attribute........................................38 5.6.23 The 'prtfl' attribute.............................................40
5.6.25 The 'structure' attribute.........................................39 5.6.24 The 'bearerType' attribute........................................40
5.6.26 The 'sbc' attribute...............................................39 5.6.25 The 'structure' attribute.........................................41
5.6.27 The 'fcpsSDUsize' and 'bcpsSDUsize' attributes....................39 5.6.26 The 'sbc' attribute...............................................41
5.6.28 The 'aal2CPS' attribute...........................................40 5.6.27 The 'fcpsSDUsize' and 'bcpsSDUsize' attributes....................41
5.6.29 The 'aal2sscs3661' attribute......................................40 5.6.28 The 'aal2CPS' attribute...........................................42
5.6.30 The 'aal2sscs3662' attribute......................................41 5.6.29 The 'aal2sscs3661' attribute......................................42
5.6.31 The 'aalApp' attribute............................................42 5.6.30 The 'aal2sscs3662' attribute......................................43
5.6.32 The 'lij' attribute...............................................43 5.6.31 The 'aalApp' attribute............................................44
5.6.34 The 'cache' attribute.............................................44 5.6.32 The 'lij' attribute...............................................45
5.6.35 Specification of Higher-layer attributes......................45 5.6.34 The 'cache' attribute.............................................46
5.6.36 Use of the second media-level part in H.323 Annex C applications45 5.6.35 Specification of Higher-layer attributes......................47
5.6.37 Chaining SDP descriptors........................................46 5.6.36 Use of the second media-level part in H.323 Annex C applications47
5.6.38 Use of the eecid media attribute in call establishment procedures46 5.6.37 Chaining SDP descriptors........................................48
6.0 List of Parameters with Representations...............................50 5.6.38 Use of the eecid media attribute in call establishment procedures48
7.0 Examples of ATM session descriptions using SDP.........................56 6.0 List of Parameters with Representations...............................52
8.0 Representation of data media..........................................57 7.0 Examples of ATM session descriptions using SDP.........................58
9.0 Security Considerations..................................................58 8.0 Representation of data media..........................................59
9.1 Bearer Security.......................................................58 9.0 Security Considerations..................................................60
9.2 Security of the SDP description.......................................58 9.1 Bearer Security.......................................................60
10. ATM SDP Grammar..........................................................58 9.2 Security of the SDP description.......................................60
10. ATM SDP Grammar..........................................................61
1. Introduction 1. Introduction
SDP will be used in conjunction with a connection handling /device SDP will be used in conjunction with a connection handling /device
control protocol such as Megaco (H.248) [26], SIP [18] or MGCP [25] to control protocol such as Megaco (H.248) [26], SIP [18] or MGCP [25] to
communicate the information needed to set up ATM and AAL2 bearer communicate the information needed to set up ATM and AAL2 bearer
connections. These connections include voice connections, voiceband data connections. These connections include voice connections, voiceband data
connections, clear channel circuit emulation connections, video connections connections, clear channel circuit emulation connections, video connections
and baseband data connections (such as fax relay, modem relay, SSCOP, and baseband data connections (such as fax relay, modem relay, SSCOP,
frame relay etc.). frame relay etc.).
These conventions use standard SDP syntax as defined in rfc2327 These conventions use standard SDP syntax as defined in rfc2327
to describe the ATM-level and AAL-level connections, addresses and to describe the ATM-level and AAL-level connections, addresses and
other parameters. In general, parameters associated with layers other parameters. In general, parameters associated with layers
higher than the ATM adaptation layer are included only if they are higher than the ATM adaptation layer are included only if they are
tightly coupled to the ATM or AAL layers. Since the syntax conforms to tightly coupled to the ATM or AAL layers. Since the syntax conforms to
rfc2327, standard SDP parsers should react in a well-defined and safe
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rfc2327, standard SDP parsers should react in a well-defined and safe
manner on receiving session descriptions based on the SDP conventions manner on receiving session descriptions based on the SDP conventions
in this document. This is done by extending the values of fields defined in in this document. This is done by extending the values of fields defined in
rfc2327 rather than by defining new fields. This is true for all SDP lines rfc2327 rather than by defining new fields. This is true for all SDP lines
except the of the media attribute lines, in which case new except the of the media attribute lines, in which case new
attributes are defined. The SDP protocol allows the definition attributes are defined. The SDP protocol allows the definition
of new attributes in the media attribute lines which are free-form. of new attributes in the media attribute lines which are free-form.
For the remaining lines, the fact that the <networkType> field in For the remaining lines, the fact that the <networkType> field in
an SDP descriptor is set to "ATM" should preclude the misinterpretation of an SDP descriptor is set to "ATM" should preclude the misinterpretation of
extended parameter values by rfc2327-compliant SDP parsers. extended parameter values by rfc2327-compliant SDP parsers.
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emphasizing keywords rather than to refer to characters or strings. emphasizing keywords rather than to refer to characters or strings.
2.3 Directionality Convention 2.3 Directionality Convention
This section defined the meaning of the terms 'forward' and This section defined the meaning of the terms 'forward' and
'backward' as used in this document. This is specially applicable 'backward' as used in this document. This is specially applicable
to parameters that have a specific direction associated with them. to parameters that have a specific direction associated with them.
In this document, 'forward' refers to the direction away from the In this document, 'forward' refers to the direction away from the
ATM node under consideration, while 'backward' refers to the direction ATM node under consideration, while 'backward' refers to the direction
towards the ATM node. This convention must be used in all SDP-based
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towards the ATM node. This convention must be used in all SDP-based
session descriptions regardless of whether underlying bearer is an SVC, a session descriptions regardless of whether underlying bearer is an SVC, a
dynamically allocated PVC/SPVC or a dynamically allocated CID. This dynamically allocated PVC/SPVC or a dynamically allocated CID. This
is regardless of which side originates the service connection. If ATM is regardless of which side originates the service connection. If ATM
SVC or AAL2 Q.2630.1 signaling is used, the directionality convention SVC or AAL2 Q.2630.1 signaling is used, the directionality convention
is independent of which side originates the SVC or AAL2 connection. is independent of which side originates the SVC or AAL2 connection.
This provides a simple way of identifying the direction in which a This provides a simple way of identifying the direction in which a
parameter is applicable, in a manner that is independent of the parameter is applicable, in a manner that is independent of the
underlying ATM or AAL2 bearer. This simplicity comes at a price, underlying ATM or AAL2 bearer. This simplicity comes at a price,
described below. described below.
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2.4 Case convention 2.4 Case convention
As defined in RFC2327 [1], SDP syntax is case-sensitive. Since these ATM As defined in RFC2327 [1], SDP syntax is case-sensitive. Since these ATM
conventions conform strictly with SDP syntax, they are case-sensitive. SDP conventions conform strictly with SDP syntax, they are case-sensitive. SDP
line types (e.g. "c", "m", "o", "a") and fields in the SDP lines should be line types (e.g. "c", "m", "o", "a") and fields in the SDP lines should be
built according to the case conventions in [1] and in this document. It is built according to the case conventions in [1] and in this document. It is
suggested, but not required, that SDP parsers for ATM applications be case- suggested, but not required, that SDP parsers for ATM applications be case-
tolerant where ignoring case does not result in ambiguity. tolerant where ignoring case does not result in ambiguity.
2.5 Use of special characters in SDP parameter values
In general, rfc2327-conformant string values of SDP parameters[1] do
not include special characters that are neither alphabets nor
digits. An exception is the "/" character used in the value "RTP/AVP"
of transport sub-field of the 'm' line.
String values used in SDP descriptions of ATM connections retain this
convention, while allowing the use of the special character "/" in a manner
commensurate with [1]. In addition, the special characters "$" and "-" are
used in the following manner. A "$" value is a wildcard that allows the
recipient of the SDP description to select any permitted value of the
parameter. A "-" value indicates that it is not necessary to specify the
value of the parameter in the SDP description because this parameter is
irrelevant for this application, or because its value can be
known from another source such as provisioning, defaults, another
protocol, another SDP descriptor or another part of the same SDP
descriptor. If the use of these special characters is construed as a
violation of rfc2327 [1] syntax, then reserved string values can be used.
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The string "CHOOSE" can be used in lieu of "$". The string "OMIT" can be
used in lieu of "-" for an omitted parameter. A decision to use special
characters or reserved keywords will be made before this internet draft
is upgraded to an rfc.
3. Capabilities Provided by SDP conventions 3. Capabilities Provided by SDP conventions
To support these applications listed in section 1, the SDP conventions in To support these applications listed in section 1, the SDP conventions in
this document provide the following session control capabilities: this document provide the following session control capabilities:
* Identification of the underlying bearer network type as ATM. * Identification of the underlying bearer network type as ATM.
* Identification by an ATM network element of its own address, * Identification by an ATM network element of its own address,
in one of several possible formats. A connection peer can in one of several possible formats. A connection peer can
initiate SVC set-up to this address. A call agent or connection initiate SVC set-up to this address. A call agent or connection
peer can select an pre-established bearer path to this address. peer can select an pre-established bearer path to this address.
* Identification of the ATM bearer connection that is to be * Identification of the ATM bearer connection that is to be
bound to the service-level connection. This is either bound to the service-level connection. This is either
a VCC in AAL1/AAL2/AAL5 applications or a channel (identified by a VCC in AAL1/AAL2/AAL5 applications or a channel (identified by
a CID) in AAL2 applications. a CID) in AAL2 applications.
* Identification of media type: audio, video, data. * Identification of media type: audio, video, data.
* In AAL1/AAL5 applications, declaration of a set of payload * In AAL1/AAL5 applications, declaration of a set of payload
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types that can be bound to the ATM bearer connection. types that can be bound to the ATM bearer connection.
RTP payload types that have been registered with IANA are RTP payload types that have been registered with IANA are
re-used for AAL1 or AAL5 [31]. In the manner of standard SDP, re-used for AAL1 or AAL5 [31]. In the manner of standard SDP,
unregistered payload types are mapped dynamically. unregistered payload types are mapped dynamically.
* In AAL2 applications, declaration of a set of profiles that * In AAL2 applications, declaration of a set of profiles that
can be bound to the ATM bearer connection. A mechanism for can be bound to the ATM bearer connection. A mechanism for
dynamically defining custom profiles within the SDP session dynamically defining custom profiles within the SDP session
description is included. This allows the use of custom description is included. This allows the use of custom
profiles for connections that span multi-network interfaces. profiles for connections that span multi-network interfaces.
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parameters, CPS parameters and SSCS parameters related the underlying parameters, CPS parameters and SSCS parameters related the underlying
bearer connection. bearer connection.
* Means for enabling or describing special functions such as leaf- * Means for enabling or describing special functions such as leaf-
initiated-join, anycast and SVC caching. initiated-join, anycast and SVC caching.
* For H.323 Annex C applications, a means of specifying the IP address * For H.323 Annex C applications, a means of specifying the IP address
and port number on which the node will receive RTCP messages. and port number on which the node will receive RTCP messages.
* A means of chaining consecutive SDP descriptors so that they refer to * A means of chaining consecutive SDP descriptors so that they refer to
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different layers of the same connection. different layers of the same connection.
4. Format of the ATM Session Description 4. Format of the ATM Session Description
The sequence of lines in the session descriptions in this document The sequence of lines in the session descriptions in this document
conforms to rfc2327 [1]. In general, a session description consists of conforms to rfc2327 [1]. In general, a session description consists of
a session-level part followed by zero or more media-level parts. ATM a session-level part followed by zero or more media-level parts. ATM
session descriptions consist of a session-level part followed by one session descriptions consist of a session-level part followed by one
or two media-level parts. The only two media applicable are the ATM or two media-level parts. The only two media applicable are the ATM
bearer medium and RTCP control (where applicable). bearer medium and RTCP control (where applicable).
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o= (origin, zero or one line) o= (origin, zero or one line)
s= (session name, zero or one line) s= (session name, zero or one line)
c= (connection information, one line) c= (connection information, one line)
b= (bandwidth, zero or more lines) b= (bandwidth, zero or more lines)
t= (timestamp, zero or one line) t= (timestamp, zero or one line)
k= (encryption key, zero or one line) k= (encryption key, zero or one line)
In ATM session descriptions, there are no media attribute lines in the In ATM session descriptions, there are no media attribute lines in the
session level part. These are present in the media-level parts. session level part. These are present in the media-level parts.
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The media level part for the ATM bearer consists of the following The media level part for the ATM bearer consists of the following
lines: lines:
m= (media information and transport address, one line) m= (media information and transport address, one line)
b= (bandwidth, zero or more lines) b= (bandwidth, zero or more lines)
k= (encryption key, zero or more lines) k= (encryption key, zero or more lines)
a= (media attribute, zero or more lines) a= (media attribute, zero or more lines)
The media level part for RTCP control consists of the following The media level part for RTCP control consists of the following
lines: lines:
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in SDP descriptors in RTSP commands to describe content bandwidth. in SDP descriptors in RTSP commands to describe content bandwidth.
The encryption key line (k=) can be used The encryption key line (k=) can be used
to indicate an encryption key for the bearer, and a method to to indicate an encryption key for the bearer, and a method to
obtain the key. At present, the encryption of ATM and AAL2 bearers obtain the key. At present, the encryption of ATM and AAL2 bearers
has not been conventionalized, unlike the encryption of RTP payloads. has not been conventionalized, unlike the encryption of RTP payloads.
Nor has the authentication or encryption of ATM or AAL2 bearer signaling. Nor has the authentication or encryption of ATM or AAL2 bearer signaling.
In the ATM and AAL2 contexts, the term 'bearer' can include 'bearer In the ATM and AAL2 contexts, the term 'bearer' can include 'bearer
signaling' as well as 'bearer payloads'. signaling' as well as 'bearer payloads'.
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The order of lines in an ATM session description is exactly in the The order of lines in an ATM session description is exactly in the
rfc2327-conformant order depicted above. However, there is no order rfc2327-conformant order depicted above. However, there is no order
of the media attribute ('a') lines with respect to other 'a' lines. of the media attribute ('a') lines with respect to other 'a' lines.
The SDP protocol version for session descriptions using these The SDP protocol version for session descriptions using these
conventions is 0. In conformance with standard SDP, it is strongly conventions is 0. In conformance with standard SDP, it is strongly
recommended that the 'v' line be included at the beginning of each recommended that the 'v' line be included at the beginning of each
SDP session description. In some contexts such as Megaco, the SDP session description. In some contexts such as Megaco, the
'v' line is optional and may be omitted unless several session 'v' line is optional and may be omitted unless several session
descriptions are provided in sequence, in which case the descriptions are provided in sequence, in which case the
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The 'o', 's' and 't' lines are included for strict conformance with The 'o', 's' and 't' lines are included for strict conformance with
RFC2327. It is possible that these lines might not carry useful RFC2327. It is possible that these lines might not carry useful
information in some ATM-based applications. information in some ATM-based applications.
Therefore, some applications might omit these lines, although Therefore, some applications might omit these lines, although
it is recommended that they not do so. For maximum it is recommended that they not do so. For maximum
interoperability, it is preferable that SDP parsers not interoperability, it is preferable that SDP parsers not
reject session descriptions that do not contain these lines. reject session descriptions that do not contain these lines.
5. Structure of the Session Description Lines 5. Structure of the Session Description Lines
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5.1 The Origin Line 5.1 The Origin Line
The origin line for an ATM-based session is structured as follows: The origin line for an ATM-based session is structured as follows:
o=<username> <sessionID><version> <networkType> o=<username> <sessionID><version> <networkType>
<ATMaddressType> <ATMaddress> <addressType> <address>
The <username> is set to "-". The <username> is set to "-".
The <sessionID> can be set to one of the following: The <sessionID> can be set to one of the following:
* an NTP timestamp referring to the moment when the SDP session * an NTP timestamp referring to the moment when the SDP session
descriptor was created. descriptor was created.
* a Call ID, connection ID or context ID that uniquely * a Call ID, connection ID or context ID that uniquely
identifies the session within the scope of the ATM node. identifies the session within the scope of the ATM node.
Since calls can comprise multiple connections (sessions), Since calls can comprise multiple connections (sessions),
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The <sessionID> field is represented as a decimal or hex number of The <sessionID> field is represented as a decimal or hex number of
up to 32 digits. A "0x" prefix is used before the hex representation. up to 32 digits. A "0x" prefix is used before the hex representation.
The <version> refers to the version of the SDP session descriptor The <version> refers to the version of the SDP session descriptor
(not that of the SDP protocol). This is can be set to one of the (not that of the SDP protocol). This is can be set to one of the
following: following:
* 0. * 0.
* an NTP timestamp referring to the moment when the SDP session * an NTP timestamp referring to the moment when the SDP session
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descriptor was modified. If the SDP session descriptor has not descriptor was modified. If the SDP session descriptor has not
been modified by an intermediate entity (such as an MGC), been modified by an intermediate entity (such as an MGC),
then the <version> timestamp will be the same as the <sessionId> then the <version> timestamp will be the same as the <sessionId>
timestamp, if any. As with the <sessionId>, only the integer part timestamp, if any. As with the <sessionId>, only the integer part
of the NTP timestamp is used. of the NTP timestamp is used.
When equated to the integer part of an NTP timestamp, the <version> field When equated to the integer part of an NTP timestamp, the <version> field
is 10 digits wide. This is more restricted than [1], which allows unlimited is 10 digits wide. This is more restricted than [1], which allows unlimited
size. As in [1], the most significant digit is non-zero when an NTP size. As in [1], the most significant digit is non-zero when an NTP
timestamp is used. timestamp is used.
The <networkType> in SDP session descriptions for ATM applications The <networkType> in SDP session descriptions for ATM applications
should be assigned the string value "ATM". should be assigned the string value "ATM" or wildcarded to a "$" or "-".
The <ATMaddressType> and <ATMaddress> parameters are identical to The <addressType> and <address> parameters are identical to
those for the connection information ('c') line. Each of these those for the connection information ('c') line (Section 5.3). Each of
parameters can be set to a "-". However, it is not recommended these parameters can be wildcarded per the conventions described
that these fields be omitted without being set to a "-" since for the 'c' line in Section 5.3. These parameters should not me omitted
this is not explicitly allowed by standard SDP (rfc2327). It since this would violate SDP syntax [1].
is recognized that some parser-builders follow this practice.
As with the 'c' line, SDP parsers are not expected to check the consistency
of <networkType> with <addressType>, <address> pairs. The <addressType>
and <address> need to be consistent with each other.
5.2 The Session Name Line 5.2 The Session Name Line
In general, the session name line is structured as follows: In general, the session name line is structured as follows:
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s=<sessionName> s=<sessionName>
For ATM-based sessions, the <sessionName> parameter is set to a "-". For ATM-based sessions, the <sessionName> parameter is set to a "-".
The resulting line is: The resulting line is:
s=- s=-
5.3 The Connection Information Line 5.3 The Connection Information Line
The connection information line for ATM-based sessions is structured In general, the connection information line [1] is structured as follows:
as follows:
c=<networkType> <ATMaddressType> <ATMaddress> c=<networkType> <addressType> <address>
The <networkType> field in the 'c' line should be set to "ATM". For ATM networks, additional values of <networkType>, <addressType>
and <address> are defined, over and above those listed in [1]. The
ABNF syntax (Section 10) for ATM SDP does not limit the ways in which
<networkType> can be combined with <addressType>, <address> pairs.
However, some combinations will not be valid in
certain applications, while others will never be valid. Invalid
combinations should be rejected by application-specific functions, and
not by generic parsers. The ABNF syntax does limit the ways in which
<addressType> and <address> can be paired.
When the SDP description is built by an ATM node such as a media gateway, For ATM networks, the value of <networkType> should be set to "ATM".
the <ATMaddress> refers to the ATM address of the node building the SDP Further, this may be wildcarded to "$" or "-". If this is done, an
node using ATM as the basic transport mechanism will select a
value of "ATM". A node that interfaces with multiple network types
("IN", "ATM" etc.) that include ATM can also choose a value of "ATM".
When the SDP description is built by a node such as a media gateway,
the <address> refers to the address of the node building the SDP
description. When this description is forwarded to another node, it still description. When this description is forwarded to another node, it still
contains the original node's ATM address. When the media gateway
Rajesh Kumar, Mohamed Mostafa. 9
contains the original node's address. When the media gateway
controller builds part or all of the SDP description, the local descriptor controller builds part or all of the SDP description, the local descriptor
can contain the ATM address of the local node, while the can contain the address of the local node, while the
remote descriptor can contain the ATM address of the remote node. remote descriptor can contain the address of the remote node.
In most applications, the <ATM address> and <ATMaddressType> in If the <address> and/or <addressType> are irrelevant or are
the local descriptor are each set to "-". known by other means, they can be wildcarded per the conventions
described below.
Additionally, in all contexts, the 'm' line can have an ATM address in the Additionally, in all contexts, the 'm' line can have an ATM address in the
<virtualConnectionId> subparameter which, if present, is the <virtualConnectionId> subparameter which, if present, is the
remote address if the 'c' line address is local, and vice versa. remote address if the 'c' line address is local, and vice versa.
The <ATMaddressType> can be NSAP, E164 or GWID (ALIAS). For ATM networks, the <addressType> can be NSAP, E164 or GWID (ALIAS).
For ATM networks, the <address> syntax depends on the syntax of
The <ATMaddress> format depends on the <ATMaddressType>. the <addressType>. SDP parsers should check the consistency
of <addressType> with <address>.
NSAP: If the ATMaddressType is NSAP, the ATMaddress is expressed in NSAP: If the addressType is NSAP, the address is expressed in
the standard dotted hex form. This is a string of 40 hex digits, the standard dotted hex form. This is a string of 40 hex digits,
with dots after the 2nd, 6th, 10th, 14th, 18th, 22nd, 26th, 30th, with dots after the 2nd, 6th, 10th, 14th, 18th, 22nd, 26th, 30th,
34th and 38th digits. The last octet of the NSAP address is the 34th and 38th digits. The last octet of the NSAP address is the
'selector' field that is available for non-standard use. An example 'selector' field that is available for non-standard use. An example
of a 'c' line with an NSAP address is: of a śc∆ line with an NSAP address is:
c=ATM NSAP 47.0091.8100.0000.0060.3e64.fd01.0060.3e64.fd01.00 c=ATM NSAP 47.0091.8100.0000.0060.3e64.fd01.0060.3e64.fd01.00
A "0x" prefix shall not be used in this case since this is always in A "0x" prefix shall not be used in this case since this is always in
hexadecimal format. hexadecimal format.
E164: If the ATMaddressType is E164, the ATMaddress is expressed as E164: If the addressType is E164, the address is expressed as
a decimal number with up to 15 digits. For example: a decimal number with up to 15 digits. For example:
c=ATM E164 9738294382 c=ATM E164 9738294382
The use of E.164 numbers in the B-ISDN context is defined in ITU E.191. The use of E.164 numbers in the B-ISDN context is defined in ITU E.191.
There is a disparity between the ATM forum and the ITU There is a disparity between the ATM forum and the ITU
in the use of E.164 numbers for ATM addressing. The ATM forum (e.g. UNI in the use of E.164 numbers for ATM addressing. The ATM forum (e.g. UNI
Signaling 4.0) allows only International Format E.164 numbers, while Signaling 4.0) allows only International Format E.164 numbers, while
the ITU (e.g. Q.2931) allows private numbering plans. Since the goal the ITU (e.g. Q.2931) allows private numbering plans. Since the goal
of this SDP specification is to interoperate with all bearer signaling of this SDP specification is to interoperate with all bearer signaling
protocols, it allows the use of numbers that do not conform to the protocols, it allows the use of numbers that do not conform to the
E.164 International Format. However, to maximize overall consistency, E.164 International Format. However, to maximize overall consistency,
network administrators can restrict the provisioning of numbers to the network administrators can restrict the provisioning of numbers to the
Rajesh Kumar, Mohamed Mostafa. 9
E.164 International Format. E.164 International Format.
GWID (ALIAS): If the ATMaddressType is GWID meaning that the address is a GWID (ALIAS): If the addressType is GWID meaning that the address is a
Gateway Identifier or Node Alias. This may or may not be globally unique. Gateway Identifier or Node Alias. This may or may not be globally unique.
In this case, the ATMaddress is expressed as alphanumeric string In this case, the address is expressed as alphanumeric string
("A"-"Z", "a"-"z", "0" - "9",".","-","_"). For example: ("A"-"Z", "a"-"z", "0" - "9",".","-","_"). For example:
c=ATM GWID officeABCmgx101vism12 c=ATM GWID officeABCmgx101vism12
Since these SDP conventions can be used for more than gateways, the Since these SDP conventions can be used for more than gateways, the
string "ALIAS" can be used instead of "GWID" in the 'c' line. Thus, string "ALIAS" can be used instead of "GWID" in the 'c' line. Thus,
the example above is equivalent to: the example above is equivalent to:
c=ATM ALIAS officeABCmgx101vism12 c=ATM ALIAS officeABCmgx101vism12
An example of a GWID (ALIAS)is the CLLI code used for telecom An example of a GWID (ALIAS)is the CLLI code used for telecom
equipment. For all practical purposes, it should be adequate for the equipment. For all practical purposes, it should be adequate for the
Rajesh Kumar, Mohamed Mostafa. 10
GWID (ALIAS) to be a variable length string with a maximum size of 32 GWID (ALIAS) to be a variable length string with a maximum size of 32
characters. characters.
The connection information line is always present in an SDP session The connection information line is always present in an SDP session
descriptor. However, if there is no address to transmit, this line descriptor. However, each of the parameters on this line can be wildcarded
can be represented in one of the following ways: to a "$" or a "-", independently of whether other parameters on this line
are wildcarded or not. Not all syntactically legal wildcard combinations
are meaningful in a particular application.
Examples of meaningful wildcard combinations in the ATM context are:
c=- - -
c=$ $ $
c=ATM - - c=ATM - -
c=ATM $ $ c=ATM $ $
c=ATM <ATMaddressType> - c=ATM <addressType> -
c=ATM <ATMaddressType> $ c=ATM <addressType> $
Specifying the ATM address type without specifying the ATM address Specifying the ATM address type without specifying the ATM address
is useful when the recipient is asked to select an ATM address of is useful when the recipient is asked to select an ATM address of
a certain type (NSAP, E.164 etc.). a certain type (NSAP, E.164 etc.).
<ATMaddressType> and/or <ATMaddress> should not omitted Examples of syntactically legal wildcard combinations of dubious utility
are:
c=- $ -
c=- $ $
c=- <addressType> -
c=$ <addressType> $
c=- <addressType> <address>
c=$ <addressType> <address>
Note that <addressType> and/or <address> should not omitted
without being set to a "-" or "$" since this would violate basic without being set to a "-" or "$" since this would violate basic
SDP syntax [1]. SDP syntax [1].
5.4 The Timestamp Line 5.4 The Timestamp Line
The timestamp line for an SDP session descriptor is structured as The timestamp line for an SDP session descriptor is structured as
follows: follows:
t= <startTime> <stopTime> t= <startTime> <stopTime>
skipping to change at line 617 skipping to change at line 680
timestamp in seconds, the fractional part of the NTP timestamp is omitted. timestamp in seconds, the fractional part of the NTP timestamp is omitted.
When equated to the integer part of an NTP timestamp, the <startTime> When equated to the integer part of an NTP timestamp, the <startTime>
field is 10 digits wide. This is more restricted than [1], which field is 10 digits wide. This is more restricted than [1], which
allows unlimited size. As in [1], the most significant digit is allows unlimited size. As in [1], the most significant digit is
non-zero when an NTP timestamp is used. non-zero when an NTP timestamp is used.
The <stopTime> parameter is set to 0 for ATM-based SDP descriptors. The <stopTime> parameter is set to 0 for ATM-based SDP descriptors.
5.5 Media Information Line for ATM connections 5.5 Media Information Line for ATM connections
Rajesh Kumar, Mohamed Mostafa. 10
The general format of the media information line adapted for AAL1 The general format of the media information line adapted for AAL1
Rajesh Kumar, Mohamed Mostafa. 11
and AAL5 applications is: and AAL5 applications is:
m=<media> <virtualConnectionId> <transport> <format list> m=<media> <virtualConnectionId> <transport> <format list>
The general format of the media information line adapted for AAL2 The general format of the media information line adapted for AAL2
applications is: applications is:
m=<media> <virtualConnectionId> <transport#1> <format list#1> m=<media> <virtualConnectionId> <transport#1> <format list#1>
<transport#2> <format list#2> ... <transport#M> <format list#M> <transport#2> <format list#2> ... <transport#M> <format list#M>
skipping to change at line 644 skipping to change at line 708
When the <transport> parameter has more than one value in the 'm' When the <transport> parameter has more than one value in the 'm'
line, the <transport> <format list> pairs can be arranged in line, the <transport> <format list> pairs can be arranged in
preferential order. preferential order.
5.5.1 The Virtual Connection ID 5.5.1 The Virtual Connection ID
The <virtualConnectionId> in AAL1 and AAL5 applications can be in The <virtualConnectionId> in AAL1 and AAL5 applications can be in
one of the following formats: one of the following formats:
* <ex_vcci> * <ex_vcci>
* <ATMaddressType>-<ATMaddress>/<ex_vcci> * <addressType>-<address>/<ex_vcci>
* <ATMaddress>/<ex_vcci> * <address>/<ex_vcci>
* <ex_bcg>/<ex_vcci> * <ex_bcg>/<ex_vcci>
* <ex_portId>/<ex_vpi>/<ex_vci> * <ex_portId>/<ex_vpi>/<ex_vci>
* <ex_bcg>/<ex_vpi>/<ex_vci> * <ex_bcg>/<ex_vpi>/<ex_vci>
* <ex_vpci>/<ex_vci> * <ex_vpci>/<ex_vci>
* <ATMaddressType>-<ATMaddress>/<ex_vpci>/<ex_vci> * <addressType>-<address>/<ex_vpci>/<ex_vci>
* <ATMaddress>/<ex_vpci>/<ex_vci> * <address>/<ex_vpci>/<ex_vci>
The <virtualConnectionId> in AAL2 applications can be in one of the The <virtualConnectionId> in AAL2 applications can be in one of the
following formats: following formats:
* <ex_vcci>/<ex_cid> * <ex_vcci>/<ex_cid>
* <ATMaddressType>-<ATMaddress>/<ex_vcci>/<ex_cid> * <addressType>-<address>/<ex_vcci>/<ex_cid>
* <ATMaddress>/<ex_vcci>/<ex_cid> * <address>/<ex_vcci>/<ex_cid>
* <ex_bcg>/<ex_vcci>/<ex_cid> * <ex_bcg>/<ex_vcci>/<ex_cid>
* <ex_portId>/<ex_vpi>/<ex_vci>/<ex_cid> * <ex_portId>/<ex_vpi>/<ex_vci>/<ex_cid>
* <ex_bcg>/<ex_vpi>/<ex_vci>/<ex_cid> * <ex_bcg>/<ex_vpi>/<ex_vci>/<ex_cid>
* <ex_vpci>/<ex_vci>/<ex_cid> * <ex_vpci>/<ex_vci>/<ex_cid>
* <ATMaddressType>-<ATMaddress>/<ex_vpci>/<ex_vci>/<ex_cid> * <addressType>-<address>/<ex_vpci>/<ex_vci>/<ex_cid>
* <ATMaddress>/<ex_vpci>/<ex_vci>/<ex_cid> * <address>/<ex_vpci>/<ex_vci>/<ex_cid>
Here, Here,
<ex_vcci> = VCCI-<vcci> <ex_vcci> = VCCI-<vcci>
<ex_vpci> = VPCI-<vpci> <ex_vpci> = VPCI-<vpci>
<ex_bcg> = BCG-<bcg> <ex_bcg> = BCG-<bcg>
<ex_portId> = PORT-<portId> <ex_portId> = PORT-<portId>
<ex_vpi> = VPI-<vpi> <ex_vpi> = VPI-<vpi>
<ex_vci> = VCI-<vci> <ex_vci> = VCI-<vci>
<ex_cid> = CID-<cid> <ex_cid> = CID-<cid>
The <vcci>, <vpi>, <vci>, <vpci> and <cid> are decimal numbers The <vcci>, <vpi>, <vci>, <vpci> and <cid> are decimal numbers
or hexadecimal numbers. An "0x" prefix is used before their values or hexadecimal numbers. An "0x" prefix is used before their values
when they are in the hex format. when they are in the hex format.
The <portId> is always a hexadecimal number. An "0x" prefix is not used The <portId> is always a hexadecimal number. An "0x" prefix is not used
Rajesh Kumar, Mohamed Mostafa. 11 Rajesh Kumar, Mohamed Mostafa. 12
with it. with it.
The <ATMaddressType> and <ATMaddress> are identical The <addressType> and <address> are identical
to their definitions above for the connection information line with to their definitions above for the connection information line with
the difference that this address refers to the remote peer in the the difference that this address refers to the remote peer in the
media information line. media information line. Since the <virtualConnectionId>, as defined
here, is meant for use in ATM networks, the values of <addressType>
and <address> in the <virtualConnectionId> are limited to ATM-specific
values.
The <vpi>, <vci> and <cid> have their usual ATM connotation. The The <vpi>, <vci> and <cid> have their usual ATM connotation. The
<vpi> is an 8 or 12 bit field. The <vci> is a 16 bit field. The <cid> <vpi> is an 8 or 12 bit field. The <vci> is a 16 bit field. The <cid>
is an 8 bit field. is an 8 bit field.
The <vpci> is a 16 bit field defined in Section 4.5.16 of ITU The <vpci> is a 16 bit field defined in Section 4.5.16 of ITU
Q.2931 [Ref. 15]. The <vpci> is similar to the <vpi>,except for its Q.2931 [Ref. 15]. The <vpci> is similar to the <vpi>,except for its
width and the fact that it retains its value across VP crossconnects. width and the fact that it retains its value across VP crossconnects.
In some applications, the size of the <vpci> is the same as the size of In some applications, the size of the <vpci> is the same as the size of
the <vpi> (8 or 12 bits). In this case, the most significant 8 or 4 bits the <vpi> (8 or 12 bits). In this case, the most significant 8 or 4 bits
skipping to change at line 739 skipping to change at line 807
The <portId> parameter is used to identify the physical trunk port The <portId> parameter is used to identify the physical trunk port
on an ATM module. It can be represented as a hexadecimal number of on an ATM module. It can be represented as a hexadecimal number of
up to 32 hex digits. up to 32 hex digits.
In some applications, it is meaningful to bundle a set of connections In some applications, it is meaningful to bundle a set of connections
between a pair of ATM nodes into a bearer connection group. The <bcg> between a pair of ATM nodes into a bearer connection group. The <bcg>
subparameter is an eight bit field that allows the bundling of up subparameter is an eight bit field that allows the bundling of up
to 255 VPCs or VCCs. to 255 VPCs or VCCs.
In some applications, it is necessary to wildcard the <virtualConnectionId> In some applications, it is necessary to wildcard the <virtualConnectionId>
Rajesh Kumar, Mohamed Mostafa. 13
parameter, or some elements of this parameter. The "$" wildcard character parameter, or some elements of this parameter. The "$" wildcard character
can be substituted for the entire <virtualConnectionId> parameter, or some can be substituted for the entire <virtualConnectionId> parameter, or some
of its terms. In the latter case, the constant strings that of its terms. In the latter case, the constant strings that
Rajesh Kumar, Mohamed Mostafa. 12
qualify the terms in the <virtualConnectionId> are retained. The qualify the terms in the <virtualConnectionId> are retained. The
concatenation <ATMaddressType>-<ATMaddress> can be wildcarded in the concatenation <addressType>-<address> can be wildcarded in the
following ways: following ways:
* The entire concatenation, <ATMaddressType>-<ATMaddress>, is * The entire concatenation, <addressType>-<address>, is
replaced with a "$". replaced with a "$".
* <ATMaddress> is replaced with a "$", but <ATMaddressType> is * <address> is replaced with a "$", but <addressType> is
not. not.
Examples of wildcarding the <virtualConnectionId> in the AAL1 and AAL5 Examples of wildcarding the <virtualConnectionId> in the AAL1 and AAL5
contexts are: $, VCCI-$, BCG-100/VPI-20/VCI-$. Examples of contexts are: $, VCCI-$, BCG-100/VPI-20/VCI-$. Examples of
wildcarding the <virtualConnectionId> in the AAL2 context are: $, wildcarding the <virtualConnectionId> in the AAL2 context are: $,
VCCI-40/CID-$, BCG-100/VPI-20/VCI-120/CID-$, NSAP-$/VCCI-$/CID-$, VCCI-40/CID-$, BCG-100/VPI-20/VCI-120/CID-$, NSAP-$/VCCI-$/CID-$,
$/VCCI-$/CID-$. $/VCCI-$/CID-$.
It is also permissible to set the entire <virtualConnectionId> parameter
to a "-" indicating its irrelevance.
5.5.2 The Transport Parameter 5.5.2 The Transport Parameter
The <transport> parameter indicates the method used to encapsulate the The <transport> parameter indicates the method used to encapsulate the
service payload. These methods are not defined in this document, which service payload. These methods are not defined in this document, which
refers to existing ATMF and ITU-T standards, which, in turn, might refers to existing ATMF and ITU-T standards, which, in turn, might
refer to other standards. For ATM applications, the following refer to other standards. For ATM applications, the following
<transport> values are defined: <transport> values are defined:
Table 1: List of Transport Parameter values used in SDP in the ATM context Table 1: List of Transport Parameter values used in SDP in the ATM context
+---------------------------------------------------------------------+ +---------------------------------------------------------------------+
skipping to change at line 799 skipping to change at line 870
| AAL2/<corporateName> | | | AAL2/<corporateName> | |
| AAL5/<corporateName> | | | AAL5/<corporateName> | |
| AAL1/IEEE:<oui> | Corporate document | | AAL1/IEEE:<oui> | Corporate document |
| AAL2/IEEE:<oui> | | | AAL2/IEEE:<oui> | |
| AAL5/IEEE:<oui> | | | AAL5/IEEE:<oui> | |
+------------------------+--------------------------------------------+ +------------------------+--------------------------------------------+
| RTP/AVP | Annex C of H.323 [45] | | RTP/AVP | Annex C of H.323 [45] |
+------------------------+--------------------------------------------+ +------------------------+--------------------------------------------+
In H.323 Annex C applications [45], the <transport> parameter has a In H.323 Annex C applications [45], the <transport> parameter has a
Rajesh Kumar, Mohamed Mostafa. 14
value of "RTP/AVP". This is because these applications use the RTP value of "RTP/AVP". This is because these applications use the RTP
protocol [2] and audio/video profile [3]. The fact that RTP is carried protocol [2] and audio/video profile [3]. The fact that RTP is carried
directly over AAL5 per [45] can be indicated explicitly via the aalApp directly over AAL5 per [45] can be indicated explicitly via the aalApp
media attribute. media attribute.
A value of "AAL1/custom", "AAL2/custom" or "AAL5/custom" for the A value of "AAL1/custom", "AAL2/custom" or "AAL5/custom" for the
Rajesh Kumar, Mohamed Mostafa. 13
<transport> parameter can indicate non-standard or semi-standard <transport> parameter can indicate non-standard or semi-standard
encapsulation schemes defined by a corporation or a multi-vendor encapsulation schemes defined by a corporation or a multi-vendor
agreement. Since there is no standard administration of this agreement. Since there is no standard administration of this
convention, care should be taken to preclude inconsistencies convention, care should be taken to preclude inconsistencies
within the scope of a deployment. within the scope of a deployment.
The use of <transport> values "AAL1/<corporateName>", The use of <transport> values "AAL1/<corporateName>",
"AAL2/<corporateName>", "AAL5/<corporateName>", "AAL1/IEEE:<oui>", "AAL2/<corporateName>", "AAL5/<corporateName>", "AAL1/IEEE:<oui>",
"AAL2/IEEE:<oui>" and "AAL5/IEEE:<oui>" is similar. These indicate "AAL2/IEEE:<oui>" and "AAL5/IEEE:<oui>" is similar. These indicate
non-standard transport mechanisms or AAL2 profiles which should non-standard transport mechanisms or AAL2 profiles which should
skipping to change at line 862 skipping to change at line 933
In the AAL2 context, the <format list> is a list of AAL2 profile In the AAL2 context, the <format list> is a list of AAL2 profile
types: types:
<profile#1> <profile#2>...<profile#n> <profile#1> <profile#2>...<profile#n>
In most applications, the ordering of profiles implies In most applications, the ordering of profiles implies
a preference (preferred profiles before less favored ones). a preference (preferred profiles before less favored ones).
The <profile> parameter is expressed as a decimal number in the The <profile> parameter is expressed as a decimal number in the
range 1-255. range 1-255.
Rajesh Kumar, Mohamed Mostafa. 15
5.5.5 Media information line construction 5.5.5 Media information line construction
Using the parameter definitions above, the 'm' for AAL1-based audio Using the parameter definitions above, the 'm' for AAL1-based audio
media can be constructed as follows: media can be constructed as follows:
m=audio <virtualConnectionId> AAL1/ATMF <payloadType#1> m=audio <virtualConnectionId> AAL1/ATMF <payloadType#1>
Rajesh Kumar, Mohamed Mostafa. 14
<payloadType#2>...<payloadType #n> <payloadType#2>...<payloadType #n>
Note that only those payload types, whether statically mapped or Note that only those payload types, whether statically mapped or
dynamically assigned, that are consistent with af-vtoa-78 [7] can be used dynamically assigned, that are consistent with af-vtoa-78 [7] can be used
in this construction. in this construction.
Backwards compatibility note: The transport value "AAL1/AVP" used in Backwards compatibility note: The transport value "AAL1/AVP" used in
previous versions of this document should be considered equivalent to previous versions of this document should be considered equivalent to
the value "AAL1/ATMF" defined above. "AAL1/AVP" is unsuitable because the value "AAL1/ATMF" defined above. "AAL1/AVP" is unsuitable because
the AVP profile is closely tied to RTP. the AVP profile is closely tied to RTP.
skipping to change at line 924 skipping to change at line 995
The 'm' for AAL5-based H.323 Annex C audio [45] can be constructed as The 'm' for AAL5-based H.323 Annex C audio [45] can be constructed as
follows: follows:
m=audio <virtualConnectionId> RTP/AVP <payloadType#1> m=audio <virtualConnectionId> RTP/AVP <payloadType#1>
<payloadType#2>...<payloadType #n> <payloadType#2>...<payloadType #n>
For example: For example:
m=audio PORT-9/VPI-3/VCI-$ RTP/AVP 2 96 m=audio PORT-9/VPI-3/VCI-$ RTP/AVP 2 96
a=rtpmap:96 X-G727-32 a=rtpmap:96 X-G727-32
Rajesh Kumar, Mohamed Mostafa. 16
a=aalType:AAL5 a=aalType:AAL5
a=aalApp:h323c a=aalApp:h323c
implies that any VCI on VPI= 3 of trunk port #9 may be used. This VC implies that any VCI on VPI= 3 of trunk port #9 may be used. This VC
encapsulates RTP packets directly on AAL5 per [45]. The 'rtpmap' (rather encapsulates RTP packets directly on AAL5 per [45]. The 'rtpmap' (rather
than the 'atmmap') attribute is used to dynamically map the payload type than the 'atmmap') attribute is used to dynamically map the payload type
Rajesh Kumar, Mohamed Mostafa. 15
of 96 into the codec name X-G727-32 (Table 2). This name represents 32 of 96 into the codec name X-G727-32 (Table 2). This name represents 32
kbps EADPCM. kbps EADPCM.
The 'm' for AAL5-based video media can be constructed as follows: The 'm' for AAL5-based video media can be constructed as follows:
m=video <virtualConnectionId> AAL5/ITU <payloadType#1> m=video <virtualConnectionId> AAL5/ITU <payloadType#1>
<payloadType#2>...<payloadType #n> <payloadType#2>...<payloadType #n>
In this case, the use of AAL5/ITU as the transport points to H.222.1 In this case, the use of AAL5/ITU as the transport points to H.222.1
as the controlling standard [51].An example 'm' line use for video media as the controlling standard [51].An example 'm' line use for video media
skipping to change at line 986 skipping to change at line 1057
a <format list>. This is because it is possible to consider definitions a <format list>. This is because it is possible to consider definitions
from multiple sources (ATMF, ITU and non-standard documents) when selecting from multiple sources (ATMF, ITU and non-standard documents) when selecting
AAL2 profile to be bound to a connection. AAL2 profile to be bound to a connection.
In most applications, the ordering of profiles implies a preference In most applications, the ordering of profiles implies a preference
(preferred profiles before less favored ones). Therefore, there can be (preferred profiles before less favored ones). Therefore, there can be
multiple instances of the same <transport> value in the same 'm' line. multiple instances of the same <transport> value in the same 'm' line.
An example 'm' line use for audio media over AAL2 is: An example 'm' line use for audio media over AAL2 is:
Rajesh Kumar, Mohamed Mostafa. 17
m=audio VCCI-27/CID-19 AAL2/ITU 7 AAL2/custom 100 AAL2/ITU 1 m=audio VCCI-27/CID-19 AAL2/ITU 7 AAL2/custom 100 AAL2/ITU 1
This indicates the use of CID #19 on VCCI #27 to carry audio. It provides This indicates the use of CID #19 on VCCI #27 to carry audio. It provides
a preferential list of profiles for this connection: profile AAL2/ITU 7 a preferential list of profiles for this connection: profile AAL2/ITU 7
defined in [13], AAL2/custom 100 defined in an application-specific or defined in [13], AAL2/custom 100 defined in an application-specific or
interoperability document and profile AAL2/ITU 1 defined in [13]. interoperability document and profile AAL2/ITU 1 defined in [13].
Rajesh Kumar, Mohamed Mostafa. 16
Another example of the use of the 'm' line use for audio media over AAL2 Another example of the use of the 'm' line use for audio media over AAL2
is: is:
m=audio VCCI-$/CID-$ AAL2/ATMF 6 8 m=audio VCCI-$/CID-$ AAL2/ATMF 6 8
This indicates that any AAL2 CID may be used, subject to any applicable This indicates that any AAL2 CID may be used, subject to any applicable
glare avoidance/reduction rules. The profiles that can be bound to this glare avoidance/reduction rules. The profiles that can be bound to this
connection are AAL2/ATMF 6 defined in af-vtoa-0113.000 [44] and AAL2/ATMF 8 connection are AAL2/ATMF 6 defined in af-vtoa-0113.000 [44] and AAL2/ATMF 8
defined in af-vmoa-0145.000 [52]. These sources use non-overlapping defined in af-vmoa-0145.000 [52]. These sources use non-overlapping
profile number ranges. The profiles they define fall under the <transport> profile number ranges. The profiles they define fall under the <transport>
skipping to change at line 1048 skipping to change at line 1119
the 'm' line indicates an unspecified profile. The media attribute lines the 'm' line indicates an unspecified profile. The media attribute lines
indicate an adaptation layer of AAL2, and the use of the audio SAP [13] indicate an adaptation layer of AAL2, and the use of the audio SAP [13]
to carry demodulated facsimile. to carry demodulated facsimile.
5.6 The Media Attribute Lines 5.6 The Media Attribute Lines
In an SDP line sequence, the media information line 'm' is In an SDP line sequence, the media information line 'm' is
followed by one or more media attribute or 'a' lines. Media followed by one or more media attribute or 'a' lines. Media
attribute lines are per the format below: attribute lines are per the format below:
Rajesh Kumar, Mohamed Mostafa. 18
a=<attribute>:<value> a=<attribute>:<value>
or or
a=<value> a=<value>
Rajesh Kumar, Mohamed Mostafa. 17
In general, media attribute lines are optional except when needed to In general, media attribute lines are optional except when needed to
qualify the media information line. This qualification is necessary qualify the media information line. This qualification is necessary
when the "m" line for an AAL1 or AAL5 session specifies a payload when the "m" line for an AAL1 or AAL5 session specifies a payload
type that needs to be dynamically mapped. The 'atmmap' media type that needs to be dynamically mapped. The 'atmmap' media
attribute line defined below is used for this purpose. attribute line defined below is used for this purpose.
In attribute lines, subparameters that are meant to be left In attribute lines, subparameters that are meant to be left
unspecified are set to a "-". These are generally inapplicable or, if unspecified are set to a "-". These are generally inapplicable or, if
applicable, are known by other means such as provisioning. In some applicable, are known by other means such as provisioning. In some
cases, a media attribute line with all parameters set to "-" carries cases, a media attribute line with all parameters set to "-" carries
skipping to change at line 1110 skipping to change at line 1181
In the Q.1901 [36] context, the eecid is synonymous with the In the Q.1901 [36] context, the eecid is synonymous with the
bnc-id (backbone network connection identifier). bnc-id (backbone network connection identifier).
* The 'aalType' attribute. This is used to indicate the nature * The 'aalType' attribute. This is used to indicate the nature
of the ATM adaptation layer (AAL). of the ATM adaptation layer (AAL).
* The 'silenceSupp' attribute, used to indicate the use of * The 'silenceSupp' attribute, used to indicate the use of
of voice activity detection for silence suppression, and to of voice activity detection for silence suppression, and to
optionally parameterize the silence suppression function. optionally parameterize the silence suppression function.
* The 'ecanf' and 'ecanb' attributes, used to indicate the use of * The 'ecanf' and 'ecanb' attributes, used to indicate the use of
of echo cancellation, and to parameterize the this function. of echo cancellation, and to parameterize the this function.
* The 'gcf' and 'gcb' attributes, used to indicate the use of * The 'gcf' and 'gcb' attributes, used to indicate the use of
Rajesh Kumar, Mohamed Mostafa. 19
of gain control, and to parameterize the this function. of gain control, and to parameterize the this function.
* The 'profileDesc' attribute which can be used to describe * The 'profileDesc' attribute which can be used to describe
AAL2 profiles. Although any AAL2 profile can be so described, AAL2 profiles. Although any AAL2 profile can be so described,
this attribute is useful for describing, at connection this attribute is useful for describing, at connection
establishment time, custom profiles that might not be known establishment time, custom profiles that might not be known
to the far end. This attribute applies in the AAL2 context to the far end. This attribute applies in the AAL2 context
Rajesh Kumar, Mohamed Mostafa. 18
only. only.
* The 'vsel' attribute which indicates a prioritized list of * The 'vsel' attribute which indicates a prioritized list of
3-tuples for voice service. Each 3-tuple indicates a codec, 3-tuples for voice service. Each 3-tuple indicates a codec,
an optional packet length and an optional packetization an optional packet length and an optional packetization
period. This complements the 'm' line information and should period. This complements the 'm' line information and should
be consistent with it. be consistent with it.
* The 'dsel' attribute which indicates a prioritized list of * The 'dsel' attribute which indicates a prioritized list of
3-tuples for voiceband data service. Each 3-tuple indicates a 3-tuples for voiceband data service. Each 3-tuple indicates a
codec, an optional packet length and an optional packetization codec, an optional packet length and an optional packetization
period. This complements the 'm' line information and should period. This complements the 'm' line information and should
skipping to change at line 1173 skipping to change at line 1244
method for AAL1 unstructured data transfer (UDT). method for AAL1 unstructured data transfer (UDT).
* The 'fec' attribute which indicates the use of * The 'fec' attribute which indicates the use of
forward error correction. forward error correction.
* The 'prtfl' attribute which indicates indicate the fill * The 'prtfl' attribute which indicates indicate the fill
level of partially filled cells. level of partially filled cells.
* The 'bearerType' attribute is used to indicate * The 'bearerType' attribute is used to indicate
whether the underlying bearer is an ATM PVC/SPVC, an ATM SVC, whether the underlying bearer is an ATM PVC/SPVC, an ATM SVC,
or an AAL2 CID connection within an existing ATM SVC/PVC/SPVC. or an AAL2 CID connection within an existing ATM SVC/PVC/SPVC.
* When present, the 'structure' attribute is used to indicate * When present, the 'structure' attribute is used to indicate
the presence or absence of AAL1 structured data transfer (SDT), the presence or absence of AAL1 structured data transfer (SDT),
Rajesh Kumar, Mohamed Mostafa. 20
and the size of the SDT blocks. and the size of the SDT blocks.
* When present, the 'sbc' media attribute line denotes the * When present, the 'sbc' media attribute line denotes the
subchannel count in the case of n x 64 clear channel subchannel count in the case of n x 64 clear channel
communication. communication.
* When present, the 'fcpsSDUsize' and 'bcpsSDUsize' * When present, the 'fcpsSDUsize' and 'bcpsSDUsize'
attributes are used to indicate the maximum size of the attributes are used to indicate the maximum size of the
Rajesh Kumar, Mohamed Mostafa. 19
CPCS SDU payload in the forward and backward directions. CPCS SDU payload in the forward and backward directions.
* When present, the 'aal2CPS' attribute is used to * When present, the 'aal2CPS' attribute is used to
indicate that an AAL2 CPS sublayer as defined in indicate that an AAL2 CPS sublayer as defined in
ITU I.363.2 [13] is associated with the VCC referred to in the ITU I.363.2 [13] is associated with the VCC referred to in the
'm' line. Optionally, it can be used to indicate selected 'm' line. Optionally, it can be used to indicate selected
CPS options and parameter values for this VCC. CPS options and parameter values for this VCC.
* When present, the 'aal2sscs3661' attribute is used to * When present, the 'aal2sscs3661' attribute is used to
indicate the presence of an AAL2 SSCS sublayer as defined indicate the presence of an AAL2 SSCS sublayer as defined
in ITU I.366.1 [12]. Optionally, it can be used to indicate in ITU I.366.1 [12]. Optionally, it can be used to indicate
selected options and parameter values for this SSCS. selected options and parameter values for this SSCS.
skipping to change at line 1216 skipping to change at line 1287
* The 'fmtp' attribute line defined in the SDP standard can be * The 'fmtp' attribute line defined in the SDP standard can be
used to describe higher-layer parameters. These pertain used to describe higher-layer parameters. These pertain
to layers higher than the ATM adaptation layer that are to layers higher than the ATM adaptation layer that are
not closely coupled with the ATM or ATM adaptation layers. not closely coupled with the ATM or ATM adaptation layers.
Examples are the B-HLI and B-LLI IEs specified in ITU Q.2931 [15], Examples are the B-HLI and B-LLI IEs specified in ITU Q.2931 [15],
and the user-to-user information element described in and the user-to-user information element described in
ITU Q.2957 [48]. ITU Q.2957 [48].
* The 'chain' attribute line is used to chain consecutive SDP * The 'chain' attribute line is used to chain consecutive SDP
descriptions. descriptions.
The base specification for SDP, rfc2327 [1], allows the definition
of new attributes. In keeping with this spirit, some of the attributes
listed above can also be used in SDP descriptions of IP
and other non-ATM sessions. For example, the 'vsel', 'dsel' and 'fsel'
attributes refer generically to codecs. These can be used for service-
specific codec negotiation and assignment in non-ATM as well as
ATM applications.
5.6.1 The 'atmmap' attribute 5.6.1 The 'atmmap' attribute
The 'atmmap' attribute is defined on the basis of the 'rtpmap' The 'atmmap' attribute is defined on the basis of the 'rtpmap'
attribute used in RFC2327. attribute used in RFC2327.
a=atmmap:<payloadType> <encodingName> a=atmmap:<payloadType> <encodingName>
The 'atmmap' attribute is used to dynamically map encoding names The 'atmmap' attribute is used to dynamically map encoding names
into payload types. This is necessary for those encoding names which into payload types. This is necessary for those encoding names which
have not been assigned a static payload type through IANA [31]. Payload have not been assigned a static payload type through IANA [31]. Payload
types and encoding techniques that have been registered with IANA types and encoding techniques that have been registered with IANA
for RTP are retained for AAL1 and AAL5. for RTP are retained for AAL1 and AAL5.
AAL5.
Rajesh Kumar, Mohamed Mostafa. 21
The range of statically defined payload types is in the range The range of statically defined payload types is in the range
0-95. All static assignments of payload types to codecs are 0-95. All static assignments of payload types to codecs are
listed in [31]. The range of payload types defined dynamically listed in [31]. The range of payload types defined dynamically
via the 'atmmap' attribute is 96-127. via the 'atmmap' attribute is 96-127.
Table 2 lists standard encoding names with their corresponding statically Table 2 lists standard encoding names with their corresponding statically
mapped payload types [31]. It also suggests encoding names for mapped payload types [31]. It also suggests encoding names for
codecs not addressed in [31]. For these, payload types are mapped codecs not addressed in [31]. For these, payload types are mapped
dynamically via the 'atmmap' attribute. Table 2 is not meant to be an dynamically via the 'atmmap' attribute. Table 2 is not meant to be an
exhaustive list of codec names. exhaustive list of codec names.
Rajesh Kumar, Mohamed Mostafa. 20 Rajesh Kumar, Mohamed Mostafa. 22
Table 2: Encoding Names and Payload Types Table 2: Encoding Names and Payload Types
|---------------------|--------------|---------------------------| |---------------------|--------------|---------------------------|
| Encoding Technique | Encoding Name| Payload type | | Encoding Technique | Encoding Name| Payload type |
|---------------------|--------------|---------------------------| |---------------------|--------------|---------------------------|
| PCM - Mu law | "PCMU" | 0 (Statically Mapped) | | PCM - Mu law | "PCMU" | 0 (Statically Mapped) |
|---------------------|--------------|---------------------------| |---------------------|--------------|---------------------------|
| 32 kbps ADPCM | "G726-32" | 2 (Statically Mapped) | | 32 kbps ADPCM | "G726-32" | 2 (Statically Mapped) |
|---------------------|--------------|---------------------------| |---------------------|--------------|---------------------------|
|Dual rate 5.3/6.3kbps| "G723" | 4 (Statically Mapped) | |Dual rate 5.3/6.3kbps| "G723" | 4 (Statically Mapped) |
|---------------------|--------------|---------------------------| |---------------------|--------------|---------------------------|
skipping to change at line 1300 skipping to change at line 1379
| suppression | | | | suppression | | |
|----------------------------------------------------------------| |----------------------------------------------------------------|
| Dual rate 5.3/6.3 |"X-G7231a-L" | None, map dynamically | | Dual rate 5.3/6.3 |"X-G7231a-L" | None, map dynamically |
| kbps - high rate w/ | | | | kbps - high rate w/ | | |
| ITU-defined silence | | | | ITU-defined silence | | |
| suppression | | | | suppression | | |
|---------------------|--------------|---------------------------| |---------------------|--------------|---------------------------|
| 16 kbps EADPCM | "X-G727-16" | None, map dynamically | | 16 kbps EADPCM | "X-G727-16" | None, map dynamically |
|---------------------|--------------|---------------------------| |---------------------|--------------|---------------------------|
Rajesh Kumar, Mohamed Mostafa. 21 Rajesh Kumar, Mohamed Mostafa. 23
+---------------------+--------------+---------------------------+ +---------------------+--------------+---------------------------+
| 24 kbps EADPCM | "X-G727-24" | None, map dynamically | | 24 kbps EADPCM | "X-G727-24" | None, map dynamically |
|---------------------|--------------|---------------------------| |---------------------|--------------|---------------------------|
| 32 kbps EADPCM | "X-G727-32" | None, map dynamically | | 32 kbps EADPCM | "X-G727-32" | None, map dynamically |
|---------------------|--------------|---------------------------| |---------------------|--------------|---------------------------|
|n x 64 kbps Clear | "X-CCD" | None, map dynamically | |n x 64 kbps Clear | "X-CCD" | None, map dynamically |
|Channel without CAS | | | |Channel without CAS | | |
|per af-vtoa-78 [7] | | | |per af-vtoa-78 [7] | | |
|---------------------|--------------|---------------------------| |---------------------|--------------|---------------------------|
|n x 64 kbps Clear | "X-CCD-CAS" | None, map dynamically | |n x 64 kbps Clear | "X-CCD-CAS" | None, map dynamically |
skipping to change at line 1358 skipping to change at line 1437
| DVI4, 11.025 KHz[3] | "DVI4" | 16 (Statically Mapped) | | DVI4, 11.025 KHz[3] | "DVI4" | 16 (Statically Mapped) |
|---------------------|--------------|---------------------------| |---------------------|--------------|---------------------------|
| DVI4, 22.05 KHz [3] | "DVI4" | 17 (Statically Mapped) | | DVI4, 22.05 KHz [3] | "DVI4" | 17 (Statically Mapped) |
|---------------------|--------------|---------------------------| |---------------------|--------------|---------------------------|
| MPEG1/MPEG2 video | "MPV" | 32 (Statically Mapped) | | MPEG1/MPEG2 video | "MPV" | 32 (Statically Mapped) |
|---------------------|--------------|---------------------------| |---------------------|--------------|---------------------------|
| MPEG 2 audio/video | "MP2T" | 33 (Statically Mapped) | | MPEG 2 audio/video | "MP2T" | 33 (Statically Mapped) |
| transport stream | | | | transport stream | | |
|---------------------|--------------|---------------------------| |---------------------|--------------|---------------------------|
Rajesh Kumar, Mohamed Mostafa. 22 Rajesh Kumar, Mohamed Mostafa. 24
|---------------------|--------------|---------------------------| |---------------------|--------------|---------------------------|
| ITU H.261 video | "H261" | 31 (Statically Mapped) | | ITU H.261 video | "H261" | 31 (Statically Mapped) |
|---------------------|--------------|---------------------------| |---------------------|--------------|---------------------------|
| ITU H.263 video | "H263" | 33 (Statically Mapped) | | ITU H.263 video | "H263" | 33 (Statically Mapped) |
|---------------------|--------------|---------------------------| |---------------------|--------------|---------------------------|
| ITU H.263 video |"H263-1998" | None, map dynamically | | ITU H.263 video |"H263-1998" | None, map dynamically |
| 1998 version | | | | 1998 version | | |
|---------------------|--------------|---------------------------| |---------------------|--------------|---------------------------|
| MPEG 1 system stream| "MP1S" | None, map dynamically | | MPEG 1 system stream| "MP1S" | None, map dynamically |
|---------------------|--------------|---------------------------| |---------------------|--------------|---------------------------|
skipping to change at line 1420 skipping to change at line 1499
requests with service-level call control signaling. requests with service-level call control signaling.
Within an SDP session description, the eecid attribute is used as Within an SDP session description, the eecid attribute is used as
follows: follows:
a=eecid:<eecid> a=eecid:<eecid>
where <eecid> consists of up to 8 hex digits (equivalent to 4 where <eecid> consists of up to 8 hex digits (equivalent to 4
octets). Since this is always represented in hex, the "0x" octets). Since this is always represented in hex, the "0x"
Rajesh Kumar, Mohamed Mostafa. 23 Rajesh Kumar, Mohamed Mostafa. 25
prefix shall not be used. prefix shall not be used.
This SDP document does not specify how the eecid (synonymous This SDP document does not specify how the eecid (synonymous
with bnc-id) is to be communicated through bearer signaling with bnc-id) is to be communicated through bearer signaling
(Q.931, UNI, PNNI, AINI, IISP, proprietary signaling equivalent, (Q.931, UNI, PNNI, AINI, IISP, proprietary signaling equivalent,
Q.2630.1). This is a task of these bearer signaling protocols. Q.2630.1). This is a task of these bearer signaling protocols.
However, the following informative statements are made to However, the following informative statements are made to
convey a sense of the interoperability that is a goal of convey a sense of the interoperability that is a goal of
current standardization efforts: current standardization efforts:
skipping to change at line 1480 skipping to change at line 1559
5.6.4 The 'silenceSupp' attribute 5.6.4 The 'silenceSupp' attribute
When present, the 'silenceSupp' attribute is used to indicate When present, the 'silenceSupp' attribute is used to indicate
the use or non-use of silence suppression. the use or non-use of silence suppression.
The format of the 'silenceSupp' media attribute line is The format of the 'silenceSupp' media attribute line is
as follows: as follows:
a=silenceSupp: <silenceSuppEnable> <silenceTimer> <suppPref> <sidUse> a=silenceSupp: <silenceSuppEnable> <silenceTimer> <suppPref> <sidUse>
<fxnslevel> <fxnslevel>
Rajesh Kumar, Mohamed Mostafa. 24 Rajesh Kumar, Mohamed Mostafa. 26
If any of the parameters in the silenceSupp media attribute line If any of the parameters in the silenceSupp media attribute line
is not specified, is inapplicable or is implied, then it is set to is not specified, is inapplicable or is implied, then it is set to
"-". "-".
The <silenceSuppEnable> can take on values of "on" or "off". If it The <silenceSuppEnable> can take on values of "on" or "off". If it
is "on", then silence suppression is enabled. is "on", then silence suppression is enabled.
The <silenceTimer> is a 16-bit field which can be represented in The <silenceTimer> is a 16-bit field which can be represented in
decimal or hex. Each increment (tick) of this timer represents decimal or hex. Each increment (tick) of this timer represents
a millisecond. The maximum value of this timer is between 1 and 3 a millisecond. The maximum value of this timer is between 1 and 3
skipping to change at line 1541 skipping to change at line 1620
In addition to the decimal representation of <fxnslevel>, a In addition to the decimal representation of <fxnslevel>, a
hex representation, preceded by a "0x" prefix, is also allowed. hex representation, preceded by a "0x" prefix, is also allowed.
5.6.5 The 'ecanf' and 'ecanb' attributes 5.6.5 The 'ecanf' and 'ecanb' attributes
When present, the 'ecanf' and 'ecanb' attributes are used to indicate When present, the 'ecanf' and 'ecanb' attributes are used to indicate
the use or non-use of echo cancellation in the forward the use or non-use of echo cancellation in the forward
and backward directions respectively. See Section and backward directions respectively. See Section
Rajesh Kumar, Mohamed Mostafa. 25 Rajesh Kumar, Mohamed Mostafa. 27
2.3 for a definition of the terms 'forward' and 'backward'. 2.3 for a definition of the terms 'forward' and 'backward'.
The format of the 'ecanf' and 'ecanb' media attribute lines is The format of the 'ecanf' and 'ecanb' media attribute lines is
as follows: as follows:
a=ecanf: <ecanEnable> <ecanType> a=ecanf: <ecanEnable> <ecanType>
a=ecanb: <ecanEnable> <ecanType> a=ecanb: <ecanEnable> <ecanType>
If any of the parameters in the ecanf and ecanb media attribute lines If any of the parameters in the ecanf and ecanb media attribute lines
is not specified, is inapplicable or is implied, then it is set to is not specified, is inapplicable or is implied, then it is set to
skipping to change at line 1604 skipping to change at line 1683
The <gcEnable> parameter can take on values of "on" or "off". If it The <gcEnable> parameter can take on values of "on" or "off". If it
is "on", then gain control is enabled. If it is "off", then is "on", then gain control is enabled. If it is "off", then
gain control is disabled. gain control is disabled.
The <gcLvl> parameter is represented as the decimal or hex The <gcLvl> parameter is represented as the decimal or hex
equivalent of a 16-bit binary field. A value of 0xFFFF implies equivalent of a 16-bit binary field. A value of 0xFFFF implies
automatic gain control. Otherwise, this number indicates the automatic gain control. Otherwise, this number indicates the
number of decibels of inserted loss. The upper bound, 65,535 dB number of decibels of inserted loss. The upper bound, 65,535 dB
Rajesh Kumar, Mohamed Mostafa. 26 Rajesh Kumar, Mohamed Mostafa. 28
(0xFFFE) of inserted loss, is an absurdly large number and is a (0xFFFE) of inserted loss, is an absurdly large number and is a
carryover from Megaco [26]. In practical applications, the inserted loss carryover from Megaco [26]. In practical applications, the inserted loss
is much lower. is much lower.
When SDP is used with some media gateway control protocols such as MGCP When SDP is used with some media gateway control protocols such as MGCP
and Megaco [26], there exist means outside SDP descriptions to specify and Megaco [26], there exist means outside SDP descriptions to specify
the gain control properties of a connection. Nevertheless, this the gain control properties of a connection. Nevertheless, this
media attribute line is included for completeness. As a result, the media attribute line is included for completeness. As a result, the
SDP can be used for describing gain control in applications SDP can be used for describing gain control in applications
where alternate means for this are unavailable. where alternate means for this are unavailable.
skipping to change at line 1665 skipping to change at line 1744
packet length in octets. packet length in octets.
The <packetTime> is a decimal integer representation of the AAL2 The <packetTime> is a decimal integer representation of the AAL2
packetization interval in ms. packetization interval in ms.
For instance, the 'profileDesc' media attribute line below defines For instance, the 'profileDesc' media attribute line below defines
the AAL2/custom 100 profile. This profile is reproduced in the Table 3 the AAL2/custom 100 profile. This profile is reproduced in the Table 3
below. For a description of the parameters in this profile such as below. For a description of the parameters in this profile such as
M and the sequence number interval, see ITU I.366.2 [13]. M and the sequence number interval, see ITU I.366.2 [13].
Rajesh Kumar, Mohamed Mostafa. 27 Rajesh Kumar, Mohamed Mostafa. 29
a=profileDesc:AAL2/custom 100 0-7 PCMG 40 5 0-7 SIDG 1 5 8-15 a=profileDesc:AAL2/custom 100 0-7 PCMG 40 5 0-7 SIDG 1 5 8-15
G726-32 40 10 8-15 SIDG 1 5 G726-32 40 10 8-15 SIDG 1 5
If the <packetTime> parameter is to be omitted or implied, then the If the <packetTime> parameter is to be omitted or implied, then the
same profile can be represented as follows: same profile can be represented as follows:
a=profileDesc:AAL2/custom 100 0-7 PCMG 40 - 0-7 SIDG 1 - 8-15 a=profileDesc:AAL2/custom 100 0-7 PCMG 40 - 0-7 SIDG 1 - 8-15
G726-32 40 - 8-15 SIDG 1 - G726-32 40 - 8-15 SIDG 1 -
If a gateway has a provisioned or hard coded definition of a If a gateway has a provisioned or hard coded definition of a
skipping to change at line 1728 skipping to change at line 1807
where the <encodingName> parameter can take one of the values in column 2 of where the <encodingName> parameter can take one of the values in column 2 of
Table 2. The <packetLength> is a decimal integer representation of the Table 2. The <packetLength> is a decimal integer representation of the
packet length in octets. The <packetTime> is a decimal integer packet length in octets. The <packetTime> is a decimal integer
representation of the packetization interval in ms. The parameters representation of the packetization interval in ms. The parameters
<packetLength>and <packetTime> can be set to "-" when not needed. Also, the <packetLength>and <packetTime> can be set to "-" when not needed. Also, the
entire 'vsel' media attribute line can be omitted when not needed. entire 'vsel' media attribute line can be omitted when not needed.
For example, For example,
Rajesh Kumar, Mohamed Mostafa. 28 Rajesh Kumar, Mohamed Mostafa. 30
a=vsel:G729 10 10 G726-32 40 10 a=vsel:G729 10 10 G726-32 40 10
indicates first preference of G.729 or G.729a (both are interoperable) as indicates first preference of G.729 or G.729a (both are interoperable) as
the voice encoding scheme. A packet length of 10 octets and a packetization the voice encoding scheme. A packet length of 10 octets and a packetization
interval of 10 ms are associated with this codec. G726-32 is the second interval of 10 ms are associated with this codec. G726-32 is the second
preference stated in this line, with an associated packet length of 40 preference stated in this line, with an associated packet length of 40
octets and a packetization interval of 10 ms. If the packet length and octets and a packetization interval of 10 ms. If the packet length and
packetization interval are intended to be omitted, then this media attribute packetization interval are intended to be omitted, then this media attribute
line becomes line becomes
a=vsel:G729 - - G726-32 - - a=vsel:G729 - - G726-32 - -
The media attribute line The media attribute line
a=vsel:G726-32 40 10 a=vsel:G726-32 40 10
indicates preference for or selection of 32 kbps ADPCM with a packet indicates preference for or selection of 32 kbps ADPCM with a packet
length of 40 octets and a packetization interval of 10 ms. length of 40 octets and a packetization interval of 10 ms.
This media attribute line can be used in the AAL1, AAL2 and This media attribute line can be used in ATM as well as non-ATM contexts.
AAL5 contexts. The <packetLength> and <packetTime> are not meaningful Within the ATM context, it can be applied to the AAL1, AAL2 and AAL5
adaptations. The <packetLength> and <packetTime> are not meaningful
in the AAL1 case and should be set to "-". In the AAL2 case, in the AAL1 case and should be set to "-". In the AAL2 case,
this line determines the use of some or all of the rows in this line determines the use of some or all of the rows in
a given profile table. If multiple 3-tuples are present, they a given profile table. If multiple 3-tuples are present, they
can indicate a hierarchical assignment of some rows in that can indicate a hierarchical assignment of some rows in that
profile to voice service e.g. row A preferred to row B etc. profile to voice service e.g. row A preferred to row B etc.
If multiple profiles are present on the 'm' line, the profile If multiple profiles are present on the 'm' line, the profile
qualified by this attribute is the first qualified by this attribute is the first
profile. If a single profile that has been selected for a connection profile. If a single profile that has been selected for a connection
is indicated in the 'm' line, the 'vsel' attribute qualifies the is indicated in the 'm' line, the 'vsel' attribute qualifies the
use, for voice service, of codecs within that profile. use, for voice service, of codecs within that profile.
skipping to change at line 1789 skipping to change at line 1869
<encodingName #N> <packetLength #N><packetTime #N> <encodingName #N> <packetLength #N><packetTime #N>
where the <encodingName> parameter can take one of the values in where the <encodingName> parameter can take one of the values in
column 2 of Table 2. The <packetLength> and <packetTime> column 2 of Table 2. The <packetLength> and <packetTime>
parameters are per their definition, above, for the 'vsel' parameters are per their definition, above, for the 'vsel'
media attribute line. The parameters <packetLength>and <packetTime>) media attribute line. The parameters <packetLength>and <packetTime>)
can be set to "-" when not needed. The <fxIncl> flag is presumed to be can be set to "-" when not needed. The <fxIncl> flag is presumed to be
"off" if it is set to "-". Also, the entire 'dsel' media attribute line "off" if it is set to "-". Also, the entire 'dsel' media attribute line
can be omitted when not needed. can be omitted when not needed.
Rajesh Kumar, Mohamed Mostafa. 29 Rajesh Kumar, Mohamed Mostafa. 31
For example, For example,
a=dsel:- G726-32 20 5 PCMU 40 5 a=dsel:- G726-32 20 5 PCMU 40 5
indicates that this line does not address facsimile, and that the indicates that this line does not address facsimile, and that the
first preference for the voiceband data codes is 32 kbps ADPCM, first preference for the voiceband data codes is 32 kbps ADPCM,
while the second preference is PCMU. The packet length while the second preference is PCMU. The packet length
and the packetization interval associated with G726-32 are 20 octets and and the packetization interval associated with G726-32 are 20 octets and
5 ms respectively. For PCMU, they are 40 octets and 5 ms respectively. 5 ms respectively. For PCMU, they are 40 octets and 5 ms respectively.
This media attribute line can be used in the AAL1, AAL2 and This media attribute line can be used in ATM as well as non-ATM contexts.
AAL5 contexts. The <packetLength> and <packetTime> are not meaningful Within the ATM context, it can be applied to the AAL1, AAL2 and AAL5
adaptations. The <packetLength> and <packetTime> are not meaningful
in the AAL1 case and should be set to "-". In the AAL2 case, in the AAL1 case and should be set to "-". In the AAL2 case,
this line determines the use of some or all of the rows in this line determines the use of some or all of the rows in
a given profile table. If multiple 3-tuples are present, they a given profile table. If multiple 3-tuples are present, they
can indicate a hierarchical assignment of some rows in that can indicate a hierarchical assignment of some rows in that
profile to voiceband data service e.g. row A preferred to row B etc. profile to voiceband data service e.g. row A preferred to row B etc.
If multiple profiles are present on the 'm' line, the profile If multiple profiles are present on the 'm' line, the profile
qualified by this attribute is the first qualified by this attribute is the first
profile. If a single profile that has been selected for a connection profile. If a single profile that has been selected for a connection
is indicated in the 'm' line, the 'dsel' attribute qualifies the is indicated in the 'm' line, the 'dsel' attribute qualifies the
use, for voiceband data service, of codecs within that profile. use, for voiceband data service, of codecs within that profile.
skipping to change at line 1848 skipping to change at line 1929
For example, For example,
a=fsel:FXDMOD-3 - - a=fsel:FXDMOD-3 - -
indicates demodulation and remodulation of ITU-T group 3 fax at the indicates demodulation and remodulation of ITU-T group 3 fax at the
gateway. gateway.
a=fsel:PCMU 40 5 G726-32 20 5 a=fsel:PCMU 40 5 G726-32 20 5
indicates a first and second preference of Mu-law PCM and 32 kbps indicates a first and second preference of Mu-law PCM and 32 kbps
ADPCM as the facsimile encoding scheme. The packet length
Rajesh Kumar, Mohamed Mostafa. 30 Rajesh Kumar, Mohamed Mostafa. 32
ADPCM as the facsimile encoding scheme. The packet length
and the packetization interval associated with G726-32 are 20 octets and and the packetization interval associated with G726-32 are 20 octets and
5 ms respectively. For PCMU, they are 40 octets and 5 ms respectively. 5 ms respectively. For PCMU, they are 40 octets and 5 ms respectively.
This media attribute line can be used in the AAL1, AAL2 and This media attribute line can be used in ATM as well as non-ATM contexts.
AAL5 contexts. The <packetLength> and <packetTime> are not meaningful Within the ATM context, it can be applied to the AAL1, AAL2 and AAL5
adaptations. The <packetLength> and <packetTime> are not meaningful
in the AAL1 case and should be set to "-". In the AAL2 case, in the AAL1 case and should be set to "-". In the AAL2 case,
this line determines the use of some or all of the rows in this line determines the use of some or all of the rows in
a given profile table. If multiple 3-tuples are present, they a given profile table. If multiple 3-tuples are present, they
can indicate a hierarchical assignment of some rows in that can indicate a hierarchical assignment of some rows in that
profile to facsimile service e.g. row A preferred to row B etc. profile to facsimile service e.g. row A preferred to row B etc.
If multiple profiles are present on the 'm' line, the profile If multiple profiles are present on the 'm' line, the profile
qualified by this attribute is the first qualified by this attribute is the first
profile. If a single profile that has been selected for a connection profile. If a single profile that has been selected for a connection
is indicated in the 'm' line, the 'fsel' attribute qualifies the is indicated in the 'm' line, the 'fsel' attribute qualifies the
use, for facsimile service, of codecs within that profile. use, for facsimile service, of codecs within that profile.
skipping to change at line 1900 skipping to change at line 1982
implications of non-standard transfer capabilities / service capabilities. implications of non-standard transfer capabilities / service capabilities.
The <subtype> field essentially serves as a subscript to the <asc> The <subtype> field essentially serves as a subscript to the <asc>
and <atc> fields. In general, it can take on any integer value, or the and <atc> fields. In general, it can take on any integer value, or the
"-" value indicating that it does not apply or that the underlying data is "-" value indicating that it does not apply or that the underlying data is
to be known by other means, such as provisioning. to be known by other means, such as provisioning.
The following combinations are recognized in the ATMF and ITU The following combinations are recognized in the ATMF and ITU
specifications: specifications:
Rajesh Kumar, Mohamed Mostafa. 33
<asc>/<atc> <subtype> Meaning <asc>/<atc> <subtype> Meaning
nrt-VBR 1 nrt-VBR.1 nrt-VBR 1 nrt-VBR.1
nrt-VBR 2 nrt-VBR.2 nrt-VBR 2 nrt-VBR.2
nrt-VBR 3 nrt-VBR.3 nrt-VBR 3 nrt-VBR.3
rt-VBR 1 rt-VBR.1 rt-VBR 1 rt-VBR.1
rt-VBR 2 rt-VBR.2 rt-VBR 2 rt-VBR.2
rt-VBR 3 rt-VBR.3 rt-VBR 3 rt-VBR.3
UBR 1 UBR.1 UBR 1 UBR.1
UBR 2 UBR.2 UBR 2 UBR.2
GFR 1 GFR.1 GFR 1 GFR.1
Rajesh Kumar, Mohamed Mostafa. 31
GFR 2 GRR.2 GFR 2 GRR.2
SBR 1 SBR1 SBR 1 SBR1
SBR 2 SBR2 SBR 2 SBR2
SBR 3 SBR3 SBR 3 SBR3
It is beyond the scope of this specification to examine the It is beyond the scope of this specification to examine the
equivalence of some of the ATMF and ITU definitions. These need to equivalence of some of the ATMF and ITU definitions. These need to
be recognized from the ATMF and ITU source specifications and exploited, be recognized from the ATMF and ITU source specifications and exploited,
as much as possible, to simplify ATM node design. as much as possible, to simplify ATM node design.
skipping to change at line 1958 skipping to change at line 2039
When present, the 'bcob' attribute represents the broadband When present, the 'bcob' attribute represents the broadband
connection oriented bearer class defined in ITU Q.2961.2 [33]. The connection oriented bearer class defined in ITU Q.2961.2 [33]. The
'bcob' media attribute line is structured as follows: 'bcob' media attribute line is structured as follows:
a=bcob:<bcob> a=bcob:<bcob>
Here, <bcob> is the decimal or hex representation of a 5-bit field. Here, <bcob> is the decimal or hex representation of a 5-bit field.
Currently, all values are unused and reserved with the following Currently, all values are unused and reserved with the following
exceptions: exceptions:
Rajesh Kumar, Mohamed Mostafa. 34
<bcob> Meaning <bcob> Meaning
1 BCOB-A 1 BCOB-A
3 BCOB-C 3 BCOB-C
16 BCOB-X 16 BCOB-X
24 BCOB-VP (transparent VP service) 24 BCOB-VP (transparent VP service)
5.6.14 The 'stc' attribute 5.6.14 The 'stc' attribute
When present, the 'stc' attribute represents susceptibility When present, the 'stc' attribute represents susceptibility
to clipping. The 'stc' media attribute line is structured as to clipping. The 'stc' media attribute line is structured as
follows: follows:
a=stc:<stc> a=stc:<stc>
Rajesh Kumar, Mohamed Mostafa. 32
Here, <stc> is the decimal equivalent of a 2-bit field. Currently, Here, <stc> is the decimal equivalent of a 2-bit field. Currently,
all values are unused and reserved with the following exceptions: all values are unused and reserved with the following exceptions:
<stc> value Binary Equivalent Meaning <stc> value Binary Equivalent Meaning
0 00 Not susceptible to clipping 0 00 Not susceptible to clipping
1 01 Susceptible to clipping 1 01 Susceptible to clipping
5.6.15 The 'upcc' attribute 5.6.15 The 'upcc' attribute
skipping to change at line 2015 skipping to change at line 2096
The 'atmQOSfparms' and 'atmQOSbparms' media attribute lines The 'atmQOSfparms' and 'atmQOSbparms' media attribute lines
are structured as follows: are structured as follows:
a=atmQOSfparms: <cdvType><acdv><ccdv><actd><cctd><aclr> a=atmQOSfparms: <cdvType><acdv><ccdv><actd><cctd><aclr>
a=atmQOSbparms: <cdvType><acdv><ccdv><actd><cctd><aclr> a=atmQOSbparms: <cdvType><acdv><ccdv><actd><cctd><aclr>
The <cdvType> parameter can take on the string values of The <cdvType> parameter can take on the string values of
"PP" and "2P". These refer to the peak-to-peak and two-point "PP" and "2P". These refer to the peak-to-peak and two-point
CDV as defined in UNI 4.0 [5] and ITU Q.2965.2 [35] respectively. CDV as defined in UNI 4.0 [5] and ITU Q.2965.2 [35] respectively.
Rajesh Kumar, Mohamed Mostafa. 35
The CDV parameters, <acdv> and <ccdv>, refer to the acceptable The CDV parameters, <acdv> and <ccdv>, refer to the acceptable
and cumulative CDVs respectively. These are expressed in units and cumulative CDVs respectively. These are expressed in units
of microseconds and represented as the decimal equivalent of microseconds and represented as the decimal equivalent
of a 24-bit field. These use the cell loss ratio, <aclr>, as the of a 24-bit field. These use the cell loss ratio, <aclr>, as the
"alpha" quantiles defined in the ATMF TM 4.1 specification [6] "alpha" quantiles defined in the ATMF TM 4.1 specification [6]
and in ITU I.356 [47]. and in ITU I.356 [47].
The CTD parameters, <actd> and <cctd>, refer to the acceptable and The CTD parameters, <actd> and <cctd>, refer to the acceptable and
cumulative CTDs respectively in milliseconds. These are represented as cumulative CTDs respectively in milliseconds. These are represented as
the decimal equivalents of 16-bit fields. These parameters are the decimal equivalents of 16-bit fields. These parameters are
equivalent to the maximum end-to-end transit delay defined in ATMF TM equivalent to the maximum end-to-end transit delay defined in ATMF TM
4.1 specification [6] and Q.2965.2 [35]. 4.1 specification [6] and Q.2965.2 [35].
The <aclr> parameter refers to forward and backward acceptable The <aclr> parameter refers to forward and backward acceptable
cell loss ratios. This is the ratio between the number of cells cell loss ratios. This is the ratio between the number of cells
lost and the number of cells transmitted. It is expressed as the decimal lost and the number of cells transmitted. It is expressed as the decimal
Rajesh Kumar, Mohamed Mostafa. 33
equivalent of an 8-bit field. This field expresses an order of equivalent of an 8-bit field. This field expresses an order of
magnitude n, where n is an integer in the range 1-15. The Cell Loss magnitude n, where n is an integer in the range 1-15. The Cell Loss
Ratio takes on the value 10 raised to the power of minus n. Ratio takes on the value 10 raised to the power of minus n.
If any of these parameters is not specified, is inapplicable or is If any of these parameters is not specified, is inapplicable or is
implied, then it is set to "-". implied, then it is set to "-".
An example use of these attributes for an rt-VBR, single-CID AAL2 An example use of these attributes for an rt-VBR, single-CID AAL2
voice VC is: voice VC is:
skipping to change at line 2077 skipping to change at line 2157
and 'atmQOSbparms' attribute lines. At present, their names serve and 'atmQOSbparms' attribute lines. At present, their names serve
as placeholders. as placeholders.
5.6.18 The 'atmFtrfcDesc' and 'atmBtrfcDesc' attributes 5.6.18 The 'atmFtrfcDesc' and 'atmBtrfcDesc' attributes
When present, the 'atmFtrfcDesc' and 'atmBtrfcDesc' attributes When present, the 'atmFtrfcDesc' and 'atmBtrfcDesc' attributes
are used to indicate ATM traffic descriptor parameters in the are used to indicate ATM traffic descriptor parameters in the
forward and backward directions respectively. See Section 2.3 for a forward and backward directions respectively. See Section 2.3 for a
definition of the terms 'forward' and 'backward'. definition of the terms 'forward' and 'backward'.
Rajesh Kumar, Mohamed Mostafa. 36
The 'atmFtrfcDesc' and 'atmBtrfcDesc' media attribute lines The 'atmFtrfcDesc' and 'atmBtrfcDesc' media attribute lines
are structured as follows: are structured as follows:
a=atmFtrfcDesc:<clpLvl> <pcr><scr><mbs><cdvt><mcr><mfs><fd><te> a=atmFtrfcDesc:<clpLvl> <pcr><scr><mbs><cdvt><mcr><mfs><fd><te>
a=atmBtrfcDesc:<clpLvl> <pcr><scr><mbs><cdvt><mcr><mfs><fd><te> a=atmBtrfcDesc:<clpLvl> <pcr><scr><mbs><cdvt><mcr><mfs><fd><te>
If any of these parameters in these media attribute lines is not If any of these parameters in these media attribute lines is not
specified, is inapplicable or is implied, then it is set to "-". specified, is inapplicable or is implied, then it is set to "-".
The <clpLvl> (CLP level) parameter indicates whether the rates and The <clpLvl> (CLP level) parameter indicates whether the rates and
bursts described in these media attribute lines apply to CLP bursts described in these media attribute lines apply to CLP
values of 0 or (0+1). It can take on the following string values: values of 0 or (0+1). It can take on the following string values:
"0", "0+1" and "-". If rates and bursts for both <clpLvl> values are to "0", "0+1" and "-". If rates and bursts for both <clpLvl> values are to
be described, then it is necessary to use two separate be described, then it is necessary to use two separate
media attribute lines for each direction in the same session media attribute lines for each direction in the same session
descriptor. If the <clpLvl> parameter is set to "-", then it descriptor. If the <clpLvl> parameter is set to "-", then it
Rajesh Kumar, Mohamed Mostafa. 34
implies that the CLP parameter is known by other means such as default, implies that the CLP parameter is known by other means such as default,
MIB provisioning etc. MIB provisioning etc.
The meaning, units and applicability of the remaining parameters The meaning, units and applicability of the remaining parameters
are per the ATMF TM 4.1 specification [6] and are reiterated below: are per the ATMF TM 4.1 specification [6] and are reiterated below:
PARAMETER MEANING UNITS APPLICABILITY PARAMETER MEANING UNITS APPLICABILITY
<pcr> PCR Cells/ CBR, rt-VBR, nrt-VBR, <pcr> PCR Cells/ CBR, rt-VBR, nrt-VBR,
second ABR, UBR, GFR; second ABR, UBR, GFR;
CLP=0,0+1 CLP=0,0+1
skipping to change at line 2136 skipping to change at line 2215
<te> CLP "on"/"off" CBR, rt-VBR, nrt-VBR, <te> CLP "on"/"off" CBR, rt-VBR, nrt-VBR,
tagging ABR, UBR, GFR; tagging ABR, UBR, GFR;
Enabled CLP=0 Enabled CLP=0
<fd> indicates that frame discard is permitted. It can take on the string <fd> indicates that frame discard is permitted. It can take on the string
values of "on" or "off". Note that, in the GFR case, frame discard values of "on" or "off". Note that, in the GFR case, frame discard
is always enabled. Hence, this subparameter can be set to "-" in is always enabled. Hence, this subparameter can be set to "-" in
the case of GFR. Since the <fd> parameter is independent the case of GFR. Since the <fd> parameter is independent
of CLP, it is meaningful in the case when <clpLvl> = "0+1". of CLP, it is meaningful in the case when <clpLvl> = "0+1".
Rajesh Kumar, Mohamed Mostafa. 37
It should be set to "-" for the case when <clpLvl> = "0". It should be set to "-" for the case when <clpLvl> = "0".
<te> (tag enable) indicates that CLP tagging is allowed. <te> (tag enable) indicates that CLP tagging is allowed.
These can take on the string values of "on" or "off". These can take on the string values of "on" or "off".
Since the <te> parameter applies only to cells with Since the <te> parameter applies only to cells with
a CLP of 0, it is meaningful in the case when <clpLvl> = "0". a CLP of 0, it is meaningful in the case when <clpLvl> = "0".
It should be set to "-" for the case when <clpLvl> = "0+1". It should be set to "-" for the case when <clpLvl> = "0+1".
An example use of these media attribute lines for an rt-VBR, An example use of these media attribute lines for an rt-VBR,
single-CID AAL2 voice VC is: single-CID AAL2 voice VC is:
a=atmFtrfcDesc:0+1 200 100 20 - - - on - a=atmFtrfcDesc:0+1 200 100 20 - - - on -
a=atmFtrfcDesc:0 200 80 15 - - - - off a=atmFtrfcDesc:0 200 80 15 - - - - off
a=atmBtrfcDesc:0+1 200 100 20 - - - on - a=atmBtrfcDesc:0+1 200 100 20 - - - on -
a=atmBtrfcDesc:0 200 80 15 - - - - off a=atmBtrfcDesc:0 200 80 15 - - - - off
Rajesh Kumar, Mohamed Mostafa. 35
This implies a forward and backward PCR of 200 cells per second This implies a forward and backward PCR of 200 cells per second
all cells regardless of CLP, forward and backward PCR of 200 cells all cells regardless of CLP, forward and backward PCR of 200 cells
per second for cells with CLP=0, a forward and backward SCR of 100 per second for cells with CLP=0, a forward and backward SCR of 100
cells per second for all cells regardless of CLP, a forward and cells per second for all cells regardless of CLP, a forward and
backward SCR of 80 cells per second for cells with CLP=0, backward SCR of 80 cells per second for cells with CLP=0,
a forward and backward MBS of 20 cells for all cells regardless a forward and backward MBS of 20 cells for all cells regardless
of CLP, a forward and backward MBS of 15 cells for cells with of CLP, a forward and backward MBS of 15 cells for cells with
CLP=0, an unspecified CDVT which can be known by other means, CLP=0, an unspecified CDVT which can be known by other means,
and an MCR and MFS which are unspecified because they are and an MCR and MFS which are unspecified because they are
inapplicable. Frame discard is enabled in both the forward and inapplicable. Frame discard is enabled in both the forward and
skipping to change at line 2198 skipping to change at line 2278
forward and backward directions respectively. See Section forward and backward directions respectively. See Section
2.3 for a definition of the terms 'forward' and 'backward'. 2.3 for a definition of the terms 'forward' and 'backward'.
The 'abrFparms' and 'abrBparms' media attribute lines are structured The 'abrFparms' and 'abrBparms' media attribute lines are structured
as follows: as follows:
a=abrFparms:<nrm><trm><cdf><adtf> a=abrFparms:<nrm><trm><cdf><adtf>
a=abrBparms:<nrm><trm><cdf><adtf> a=abrBparms:<nrm><trm><cdf><adtf>
These parameters are mapped into the ABR service parameters in These parameters are mapped into the ABR service parameters in
Rajesh Kumar, Mohamed Mostafa. 38
[6] in the manner described below. These parameters can be [6] in the manner described below. These parameters can be
represented in SDP as decimal integers, with fractions permitted represented in SDP as decimal integers, with fractions permitted
for some. Details of the meaning, units and applicability of for some. Details of the meaning, units and applicability of
these parameters are in [5] and [6]. these parameters are in [5] and [6].
If any of these parameters in the 'abrFparms' or 'abrBparms' media If any of these parameters in the 'abrFparms' or 'abrBparms' media
attribute lines is not specified, is inapplicable or is implied, attribute lines is not specified, is inapplicable or is implied,
then it is set to "-". then it is set to "-".
In SDP, these parameters are represented as the decimal or hex In SDP, these parameters are represented as the decimal or hex
equivalent of the binary fields mentioned below. equivalent of the binary fields mentioned below.
Rajesh Kumar, Mohamed Mostafa. 36
+-----------+----------------------------------+-----------------------+ +-----------+----------------------------------+-----------------------+
| PARAMETER | MEANING | FIELD SIZE | | PARAMETER | MEANING | FIELD SIZE |
+-----------+----------------------------------+-----------------------+ +-----------+----------------------------------+-----------------------+
| <nrm> | Maximum number of cells per | 3 bits | | <nrm> | Maximum number of cells per | 3 bits |
| | forward Resource Management cell | | | | forward Resource Management cell | |
+-----------+----------------------------------+-----------------------+ +-----------+----------------------------------+-----------------------+
| <trm> | Maximum time between | 3 bits | | <trm> | Maximum time between | 3 bits |
| | forward Resource Management cells| | | | forward Resource Management cells| |
+-----------+----------------------------------+-----------------------+ +-----------+----------------------------------+-----------------------+
| <cdf> | Cutoff Decrease Factor | 3 bits | | <cdf> | Cutoff Decrease Factor | 3 bits |
skipping to change at line 2260 skipping to change at line 2341
forward error correction. Currently, there exists a forward error forward error correction. Currently, there exists a forward error
correction method defined for AAL1 in ITU I.363.1 [10]. The format of the correction method defined for AAL1 in ITU I.363.1 [10]. The format of the
'fec' media attribute line is as follows: 'fec' media attribute line is as follows:
a=fec:<fecEnable> a=fec:<fecEnable>
The <fecEnable> flag indicates the presence of absence of Forward The <fecEnable> flag indicates the presence of absence of Forward
Error Correction. It can take on the string values of "NULL", Error Correction. It can take on the string values of "NULL",
"LOSS_SENSITIVE" and "DELAY_SENSITIVE". An "NULL" value implies disabling "LOSS_SENSITIVE" and "DELAY_SENSITIVE". An "NULL" value implies disabling
this capability. FEC can be enabled differently for delay-sensitive this capability. FEC can be enabled differently for delay-sensitive
Rajesh Kumar, Mohamed Mostafa. 39
and loss-sensitive connections. and loss-sensitive connections.
5.6.23 The 'prtfl' attribute 5.6.23 The 'prtfl' attribute
When present, the 'prtfl' attribute is used to indicate the fill When present, the 'prtfl' attribute is used to indicate the fill
level of cells. When this attribute is absent, then level of cells. When this attribute is absent, then
other means (such as provisionable defaults) are used to determine other means (such as provisionable defaults) are used to determine
the presence and level of partial fill. the presence and level of partial fill.
This attribute indicates the number of non-pad payload This attribute indicates the number of non-pad payload
octets, not including any AAL SAR or convergence sublayer octets. For octets, not including any AAL SAR or convergence sublayer octets. For
example, in some AAL1 applications that use partially filled cells with example, in some AAL1 applications that use partially filled cells with
Rajesh Kumar, Mohamed Mostafa. 37
padding at the end, this attribute indicates the number of leading padding at the end, this attribute indicates the number of leading
payload octets not including any AAL overhead. payload octets not including any AAL overhead.
The format of the 'prtfl' media attribute line is as follows: The format of the 'prtfl' media attribute line is as follows:
a=prtfl:<partialFill> a=prtfl:<partialFill>
Here, <partialFill> can be expressed as a decimal or a hex integer. Here, <partialFill> can be expressed as a decimal or a hex integer.
In general, permitted values are integers in the range 1 - 48 In general, permitted values are integers in the range 1 - 48
inclusive. However, this upper bound is different for different inclusive. However, this upper bound is different for different
skipping to change at line 2323 skipping to change at line 2404
(Q.2931-based or Q.2630.1 based). The format of the 'bearerType' (Q.2931-based or Q.2630.1 based). The format of the 'bearerType'
media attribute line is as follows: media attribute line is as follows:
a=bearerType: <bearerType> <localInititiation> a=bearerType: <bearerType> <localInititiation>
The <bearerType> field can take on the following string values: The <bearerType> field can take on the following string values:
"PVC", "SVC", "CID", with semantics as defined above. Here, "PVC" "PVC", "SVC", "CID", with semantics as defined above. Here, "PVC"
includes both the PVC and SPVC cases. includes both the PVC and SPVC cases.
In the case when the underlying bearer is a PVC/SPVC, or a CID In the case when the underlying bearer is a PVC/SPVC, or a CID
Rajesh Kumar, Mohamed Mostafa. 40
assigned by the MGC rather than through bearer signaling, the assigned by the MGC rather than through bearer signaling, the
<localInititiation> flag can be omitted or set to "-". In the <localInititiation> flag can be omitted or set to "-". In the
case when bearer signaling is used, this flag can be omitted case when bearer signaling is used, this flag can be omitted
when it is known by default or by other means whether the media when it is known by default or by other means whether the media
gateway initiates the connection set-up via bearer signaling. Only gateway initiates the connection set-up via bearer signaling. Only
when this is to be indicated explicitly that the <localInititiation> when this is to be indicated explicitly that the <localInititiation>
flag takes on the values of "on" or "off". An "on" value indicates flag takes on the values of "on" or "off". An "on" value indicates
that the media gateway is responsible for initiating connection set-up that the media gateway is responsible for initiating connection set-up
via bearer signaling (SVC signaling or Q.2630.1 signaling), via bearer signaling (SVC signaling or Q.2630.1 signaling),
an "off" value indicates otherwise. an "off" value indicates otherwise.
Rajesh Kumar, Mohamed Mostafa. 38
5.6.25 The 'structure' attribute 5.6.25 The 'structure' attribute
This attribute applies to AAL1 connections only. When present, This attribute applies to AAL1 connections only. When present,
the 'structure' attribute is used to indicate the presence or the 'structure' attribute is used to indicate the presence or
absence of structured data transfer (SDT), and the size in octets absence of structured data transfer (SDT), and the size in octets
of the SDT blocks. The format of the 'structure' media attribute line of the SDT blocks. The format of the 'structure' media attribute line
is as follows: is as follows:
a=structure: <structureEnable> <blksz> a=structure: <structureEnable> <blksz>
skipping to change at line 2385 skipping to change at line 2466
aggregated for transmitting clear channel data. For T1-based aggregated for transmitting clear channel data. For T1-based
applications, it can take on integral values in the inclusive range applications, it can take on integral values in the inclusive range
[1...24]. For E1-based applications, it can take on integral values in [1...24]. For E1-based applications, it can take on integral values in
the inclusive range [1...31]. When omitted, other means are to be used the inclusive range [1...31]. When omitted, other means are to be used
to determine the subchannel count. to determine the subchannel count.
5.6.27 The 'fcpsSDUsize' and 'bcpsSDUsize' attributes 5.6.27 The 'fcpsSDUsize' and 'bcpsSDUsize' attributes
When present, the 'fcpsSDUsize' and 'bcpsSDUsize' attributes are used to When present, the 'fcpsSDUsize' and 'bcpsSDUsize' attributes are used to
indicate the maximum size of the CPCS SDU payload in the forward and indicate the maximum size of the CPCS SDU payload in the forward and
Rajesh Kumar, Mohamed Mostafa. 41
backward directions respectively. See section 2.3 for a definition of the backward directions respectively. See section 2.3 for a definition of the
terms 'forward' and 'backward'. The format of these media attribute lines is terms 'forward' and 'backward'. The format of these media attribute lines is
as follows: as follows:
a=fcpsSDUsize: <cpcs> a=fcpsSDUsize: <cpcs>
a=bcpsSDUsize: <cpcs> a=bcpsSDUsize: <cpcs>
The <cpcs> fields is a 16-bit integer that can be represented in The <cpcs> fields is a 16-bit integer that can be represented in
decimal or in hex. decimal or in hex.
Rajesh Kumar, Mohamed Mostafa. 39
The meaning and values of these fields are as follows: The meaning and values of these fields are as follows:
Application Field Meaning Values Application Field Meaning Values
AAL5 <cpcs> Maximum CPCS-SDU size 1- 65,535 AAL5 <cpcs> Maximum CPCS-SDU size 1- 65,535
AAL2 <cpcs> Maximum CPCS-SDU size 45 or 64 AAL2 <cpcs> Maximum CPCS-SDU size 45 or 64
In certain applications (such as SIP-based applications), an SDP In certain applications (such as SIP-based applications), an SDP
descriptor might have both the fcpsSDUsize and bcpsSDUsize descriptor might have both the fcpsSDUsize and bcpsSDUsize
skipping to change at line 2446 skipping to change at line 2527
This SSCS can be selected via the aalApp attribute defined below This SSCS can be selected via the aalApp attribute defined below
or through the 'aal2_SSCS_3661' attribute. The format of this or through the 'aal2_SSCS_3661' attribute. The format of this
media attribute line is as follows: media attribute line is as follows:
a=aal2sscs3661:<adt> <ted> <fsssar> <bsssar> a=aal2sscs3661:<adt> <ted> <fsssar> <bsssar>
Each of these fields can be set to a "-" when the intention is to not Each of these fields can be set to a "-" when the intention is to not
specify them in an SDP descriptor. specify them in an SDP descriptor.
The <adt> flag indicates the presence of absence of assured data The <adt> flag indicates the presence of absence of assured data
Rajesh Kumar, Mohamed Mostafa. 42
transfer as defined in I.366.1. The <ted> flag indicates the transfer as defined in I.366.1. The <ted> flag indicates the
presence of absence of transmission error detection as defined presence of absence of transmission error detection as defined
in I.366.1. Each of these flags can take on the values of "on" in I.366.1. Each of these flags can take on the values of "on"
or "off". An "on" value indicates presence of the capability. or "off". An "on" value indicates presence of the capability.
The <fsssar> and <bsssar> fields are 16-bit integers that The <fsssar> and <bsssar> fields are 16-bit integers that
can be represented in decimal or in hex. The meaning and values of can be represented in decimal or in hex. The meaning and values of
the <fsssar> and <bsssar> fields are as follows: the <fsssar> and <bsssar> fields are as follows:
Rajesh Kumar, Mohamed Mostafa. 40
Field Meaning Values Field Meaning Values
<fsssar> Maximum SSSAR-SDU size 1- 65,535 <fsssar> Maximum SSSAR-SDU size 1- 65,535
forward direction forward direction
<bsssar> Maximum SSSAR-SDU size 1- 65,535 <bsssar> Maximum SSSAR-SDU size 1- 65,535
backward direction backward direction
In certain applications (such as SIP-based applications), an SDP In certain applications (such as SIP-based applications), an SDP
descriptor might have an 'aal2sscs3661' media attribute line descriptor might have an 'aal2sscs3661' media attribute line
skipping to change at line 2508 skipping to change at line 2590
mode data is enabled or disabled, corresponding to the string mode data is enabled or disabled, corresponding to the string
values of "on" and "off" respectively. values of "on" and "off" respectively.
The <faxDemod> flag indicates whether facsimile demodulation The <faxDemod> flag indicates whether facsimile demodulation
and remodulation are enabled or disabled, corresponding to the and remodulation are enabled or disabled, corresponding to the
string values of "on" and "off" respectively. string values of "on" and "off" respectively.
The <cas> flag indicates whether the transport of Channel The <cas> flag indicates whether the transport of Channel
Associated Signaling (CAS) bits in AAL2 type 3 packets is enabled Associated Signaling (CAS) bits in AAL2 type 3 packets is enabled
or disabled, corresponding to the string values of "on" and "off" or disabled, corresponding to the string values of "on" and "off"
Rajesh Kumar, Mohamed Mostafa. 43
respectively. respectively.
The <dtmf> flag indicates whether the transport of DTMF dialled The <dtmf> flag indicates whether the transport of DTMF dialled
digits in AAL2 type 3 packets is enabled or disabled, corresponding digits in AAL2 type 3 packets is enabled or disabled, corresponding
to the string values of "on" and "off" respectively. to the string values of "on" and "off" respectively.
The <mfall> flag indicates whether the transport of MF dialled The <mfall> flag indicates whether the transport of MF dialled
Rajesh Kumar, Mohamed Mostafa. 41
digits in AAL2 type 3 packets is enabled or disabled, corresponding digits in AAL2 type 3 packets is enabled or disabled, corresponding
to the string values of "on" and "off" respectively. This flag to the string values of "on" and "off" respectively. This flag
enables MF dialled digits in a generic manner, without specifying enables MF dialled digits in a generic manner, without specifying
type (e.g. R1, R2 etc.). type (e.g. R1, R2 etc.).
The <mfr1> flag indicates whether the transport, in AAL2 type 3 The <mfr1> flag indicates whether the transport, in AAL2 type 3
packets, of MF dialled digits for signaling system R1 is enabled packets, of MF dialled digits for signaling system R1 is enabled
or disabled, corresponding to the string values of "on" and "off" or disabled, corresponding to the string values of "on" and "off"
respectively. respectively.
skipping to change at line 2568 skipping to change at line 2650
5.6.31 The 'aalApp' attribute 5.6.31 The 'aalApp' attribute
When present, the 'aalApp' attribute is used to point to the When present, the 'aalApp' attribute is used to point to the
controlling standard for an application layer above the ATM adaptation controlling standard for an application layer above the ATM adaptation
layer. The format of the 'aalApp' media attribute line is as follows: layer. The format of the 'aalApp' media attribute line is as follows:
a=aalApp: <aalApp> a=aalApp: <aalApp>
The <aalApp> field can take on the string values listed The <aalApp> field can take on the string values listed
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below, along with their meaning. Note that most applications which are below, along with their meaning. Note that most applications which are
specified to run on AAL5 can also run on one or more of the AAL2 specified to run on AAL5 can also run on one or more of the AAL2
SSCS variants (TED and ADT) specified in I.366.1. SSCS variants (TED and ADT) specified in I.366.1.
This list is not exhaustive. Other values are possible. If used, these need This list is not exhaustive. An "X-" prefix should be used with
to be defined consistently across an application. non-standard values, not listed here, of the <aalApp> parameter.
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<aalApp> Meaning <aalApp> Meaning
"itu_h323c" Annex C of H.323 which specifies direct "itu_h323c" Annex C of H.323 which specifies direct
RTP on AAL5 [45]. RTP on AAL5 [45].
"af83" af-vtoa-0083.001, which specifies "af83" af-vtoa-0083.001, which specifies
variable size AAL5 PDUs with PCM voice variable size AAL5 PDUs with PCM voice
and a null SSCS [46]. and a null SSCS [46].
"assuredSSCOP" SSCOP as defined in ITU Q.2110 [43], "assuredSSCOP" SSCOP as defined in ITU Q.2110 [43],
skipping to change at line 2629 skipping to change at line 2712
parameters associated with this capability. The format of the parameters associated with this capability. The format of the
'lij' media attribute line is as follows: 'lij' media attribute line is as follows:
a=lij: <sci><lsn> a=lij: <sci><lsn>
The <sci> (screening indication) is a 4-bit field expressed as a The <sci> (screening indication) is a 4-bit field expressed as a
decimal or hex integer. It is defined in the UNI 4.0 signaling decimal or hex integer. It is defined in the UNI 4.0 signaling
specification [5]. It is possible that the values of this field will specification [5]. It is possible that the values of this field will
be defined later by the ATMF and/or ITU. Currently, all values are be defined later by the ATMF and/or ITU. Currently, all values are
reserved with the exception of 0, which indicates a 'Network Join reserved with the exception of 0, which indicates a 'Network Join
Rajesh Kumar, Mohamed Mostafa. 45
without Root Notification'. without Root Notification'.
The <lsn> (leaf sequence number) is a 32-bit field expressed as a The <lsn> (leaf sequence number) is a 32-bit field expressed as a
decimal or hex integer. Per the UNI 4.0 signaling specification [5], it decimal or hex integer. Per the UNI 4.0 signaling specification [5], it
is used by a joining leaf to associate messages and responses during is used by a joining leaf to associate messages and responses during
LIJ (leaf initiated join) procedures. LIJ (leaf initiated join) procedures.
Rajesh Kumar, Mohamed Mostafa. 43
Each of these fields can be set to a "-" when the intention Each of these fields can be set to a "-" when the intention
is to not specify them in an SDP descriptor. is to not specify them in an SDP descriptor.
5.6.33 The 'anycast' attribute 5.6.33 The 'anycast' attribute
When present, the 'anycast' attribute line is used to indicate When present, the 'anycast' attribute line is used to indicate
the applicability of the anycast function described in UNI the applicability of the anycast function described in UNI
4.0 [5]. Optional parameters to qualify this function are 4.0 [5]. Optional parameters to qualify this function are
provided. The format of the 'anycast' attribute is: provided. The format of the 'anycast' attribute is:
skipping to change at line 2690 skipping to change at line 2774
has the following format: has the following format:
a=cache:<cacheEnable><cacheTimer> a=cache:<cacheEnable><cacheTimer>
The <cacheEnable> flag indicates whether caching is enabled or The <cacheEnable> flag indicates whether caching is enabled or
not, corresponding to the string values of "on" and "off" not, corresponding to the string values of "on" and "off"
respectively. respectively.
The <cacheTimer> indicates the period of inactivity following which The <cacheTimer> indicates the period of inactivity following which
the SVC is to be released by sending an SVC release message into the SVC is to be released by sending an SVC release message into
Rajesh Kumar, Mohamed Mostafa. 46
the network. This is specified as the decimal or hex equivalent of the network. This is specified as the decimal or hex equivalent of
a 32-bit field, indicating the timeout in seconds. As usual, leading a 32-bit field, indicating the timeout in seconds. As usual, leading
zeros can be omitted. For instance, zeros can be omitted. For instance,
a=cache:on 7200 a=cache:on 7200
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implies that the cached SVC is to be deleted if it is idle for 2 hours. implies that the cached SVC is to be deleted if it is idle for 2 hours.
The <cacheTimer> can be set to "-" if it is inapplicable or implied. The <cacheTimer> can be set to "-" if it is inapplicable or implied.
5.6.35 Specification of Higher-layer attributes 5.6.35 Specification of Higher-layer attributes
This conventions in this ATM SDP document are limited to the ATM and adaptation This conventions in this ATM SDP document are limited to the ATM and adaptation
layers. Parameters associated with layers higher than the ATM adaptation layers. Parameters associated with layers higher than the ATM adaptation
layer are addressed only if these are tightly coupled to the ATM or layer are addressed only if these are tightly coupled to the ATM or
adaptation layers. adaptation layers.
skipping to change at line 2751 skipping to change at line 2836
media-level part pertains to RTCP only. media-level part pertains to RTCP only.
The <rtcpPortNum> and <rtcpIPaddr> subparameters indicate the port number The <rtcpPortNum> and <rtcpIPaddr> subparameters indicate the port number
and IP address on which the media gateway is prepared to receive RTCP packets. and IP address on which the media gateway is prepared to receive RTCP packets.
Any of the subparameters on these lines can be set to "-" if they are known by Any of the subparameters on these lines can be set to "-" if they are known by
other means. other means.
The range and format of the <rtcpPortNum> and <rtcpIPaddr> subparameters is per The range and format of the <rtcpPortNum> and <rtcpIPaddr> subparameters is per
[1]. The <rtcpPortNum> is a decimal number between 1024 and 65535. It is an odd [1]. The <rtcpPortNum> is a decimal number between 1024 and 65535. It is an odd
Rajesh Kumar, Mohamed Mostafa. 47
number. If an even number in this range is specified, the next odd number is number. If an even number in this range is specified, the next odd number is
used. The <rtcpIPaddr> is expressed in the usual dotted decimal IP address used. The <rtcpIPaddr> is expressed in the usual dotted decimal IP address
representation, from 0.0.0.0 to 255.255.255.255. representation, from 0.0.0.0 to 255.255.255.255.
Rajesh Kumar, Mohamed Mostafa. 45
5.6.37 Chaining SDP descriptors 5.6.37 Chaining SDP descriptors
The start of an SDP descriptor is marked by a 'v' line. In some The start of an SDP descriptor is marked by a 'v' line. In some
applications, consecutive SDP descriptions are alternative descriptions applications, consecutive SDP descriptions are alternative descriptions
of the same session. In others, these describe different layers of the of the same session. In others, these describe different layers of the
same connection (e.g. IP, ATM, frame relay). This is useful when these same connection (e.g. IP, ATM, frame relay). This is useful when these
connectivity at these layers are established at the same time e.g. an connectivity at these layers are established at the same time e.g. an
IP-based session over an ATM SVC. To distinguish between the IP-based session over an ATM SVC. To distinguish between the
alternation and concatenation of SDP descriptions, a 'chain' attribute alternation and concatenation of SDP descriptions, a 'chain' attribute
can be used in the case of concatenation. can be used in the case of concatenation.
skipping to change at line 2802 skipping to change at line 2888
This informative section supplements the definition of the eecid This informative section supplements the definition of the eecid
attribute (Section 5.6.2) by describing example procedures for its use. attribute (Section 5.6.2) by describing example procedures for its use.
These procedures assume a bearer-signaling mechanism for connection set-up These procedures assume a bearer-signaling mechanism for connection set-up
that is independent of service-level call control. These procedures are that is independent of service-level call control. These procedures are
independent of the media gateway control protocol (MGCP, Megaco, SIP etc.), independent of the media gateway control protocol (MGCP, Megaco, SIP etc.),
the protocol used between media gateway controllers (ITU Q.1901, SIP the protocol used between media gateway controllers (ITU Q.1901, SIP
etc.) and the protocol used for bearer connection set-up (Q.2931, UNI, PNNI, etc.) and the protocol used for bearer connection set-up (Q.2931, UNI, PNNI,
AINI, IISP, Q.2630.1 etc.). AINI, IISP, Q.2630.1 etc.).
Rajesh Kumar, Mohamed Mostafa. 48
Inter-MGC Inter-MGC
+---------+ Protocol +---------+ +---------+ Protocol +---------+
| MGC |------------------| MGC | | MGC |------------------| MGC |
+---------+ +---------+ +---------+ +---------+
| | | |
|Media Gateway |Media Gateway |Media Gateway |Media Gateway
|Control Protocol |Control Protocol |Control Protocol |Control Protocol
| | | |
+------------+ (ATM Network) +------------+ +------------+ (ATM Network) +------------+
|Originating |------------------|Terminating | |Originating |------------------|Terminating |
|Media | Bearer Setup |Media | |Media | Bearer Setup |Media |
|Gateway | Protocol |Gateway | |Gateway | Protocol |Gateway |
+------------+ +------------+ +------------+ +------------+
In the diagram above, the originating media gateway originates the service- In the diagram above, the originating media gateway originates the service-
level call. The terminating media gateway terminates it. In the forward call level call. The terminating media gateway terminates it. In the forward call
Rajesh Kumar, Mohamed Mostafa. 46
model, the originating media gateway initiates bearer connection set-up. In the model, the originating media gateway initiates bearer connection set-up. In the
backward call model, the terminating gateway initiates bearer connection set- backward call model, the terminating gateway initiates bearer connection set-
up. up.
Example use of the Backward Call Model: Example use of the Backward Call Model:
(1) The originating media gateway controller (OMGC) initiates service-level (1) The originating media gateway controller (OMGC) initiates service-level
call establishment by sending the appropriate control message to the call establishment by sending the appropriate control message to the
originating media gateway (OMG). originating media gateway (OMG).
(2) The originating media gateway (OMG) provides its NSAP address and an eecid (2) The originating media gateway (OMG) provides its NSAP address and an eecid
skipping to change at line 2860 skipping to change at line 2944
includes the session descriptor received from the OMG. This includes the session descriptor received from the OMG. This
descriptor contains the NSAP address of the OMG and the EECID descriptor contains the NSAP address of the OMG and the EECID
assigned by the OMG. Additionally, the TMGC instructs the TMG assigned by the OMG. Additionally, the TMGC instructs the TMG
to set up an SVC to the OMG. It also requests the TMG to notify to set up an SVC to the OMG. It also requests the TMG to notify
the TMGC when SVC set-up is complete. Depending on the control the TMGC when SVC set-up is complete. Depending on the control
protocol used, this can be done through a variety of means. protocol used, this can be done through a variety of means.
In the Megaco context, the request to set-up an SVC (not the In the Megaco context, the request to set-up an SVC (not the
notification request for the SVC set-up event) can be made through notification request for the SVC set-up event) can be made through
the following local descriptor: the following local descriptor:
Rajesh Kumar, Mohamed Mostafa. 49
v=0 v=0
o=- 2873397497 0 ATM - - o=- 2873397497 0 ATM - -
s=- s=-
c=ATM - - c=ATM - -
t=0 0 t=0 0
m=audio $ - - m=audio $ - -
a=bearerType:SVC on a=bearerType:SVC on
The 'bearerType' attribute indicates that an SVC is to be used and The 'bearerType' attribute indicates that an SVC is to be used and
that the <localInititiation> flag is on i.e. the SVC is to be set up that the <localInititiation> flag is on i.e. the SVC is to be set up
by the TMG. by the TMG.
(5) The TMG acknowledges the control message from the TMGC. It returns (5) The TMG acknowledges the control message from the TMGC. It returns
the following SDP descriptor with the acknowledge: the following SDP descriptor with the acknowledge:
Rajesh Kumar, Mohamed Mostafa. 47
v=0 v=0
o=- 2873397498 0 ATM NSAP o=- 2873397498 0 ATM NSAP
47.0091.8100.0000.0040.2A74.EB03.0020.4421.2A04.00 47.0091.8100.0000.0040.2A74.EB03.0020.4421.2A04.00
s=- s=-
c=ATM NSAP c=ATM NSAP
47.0091.8100.0000.0040.2A74.EB03.0020.4421.2A04.00 47.0091.8100.0000.0040.2A74.EB03.0020.4421.2A04.00
t=0 0 t=0 0
m=audio $ AAL2/ITU 8 m=audio $ AAL2/ITU 8
The NSAP address information provided in this descriptor is not needed. The NSAP address information provided in this descriptor is not needed.
skipping to change at line 2922 skipping to change at line 3005
47.0091.8100.0000.0060.3E64.FD01.0060.3E64.FD01.00 47.0091.8100.0000.0060.3E64.FD01.0060.3E64.FD01.00
s=- s=-
c=ATM NSAP c=ATM NSAP
47.0091.8100.0000.0060.3E64.FD01.0060.3E64.FD01.00 47.0091.8100.0000.0060.3E64.FD01.0060.3E64.FD01.00
t=0 0 t=0 0
m=audio $ AAL2/ITU 8 m=audio $ AAL2/ITU 8
The NSAP address information provided in this descriptor is not needed. The NSAP address information provided in this descriptor is not needed.
It can be omitted (by setting it to "- -"). It can be omitted (by setting it to "- -").
Rajesh Kumar, Mohamed Mostafa. 50
(3) The originating media gateway controller (OMGC) signals (3) The originating media gateway controller (OMGC) signals
the terminating media gateway controller (TMGC) through the terminating media gateway controller (TMGC) through
the appropriate mechanism (ISUP with Q.1901 extensions, SIP etc.). the appropriate mechanism (ISUP with Q.1901 extensions, SIP etc.).
Although this is not necessary, it can provide the TMGC with the Although this is not necessary, it can provide the TMGC with the
NSAP address provided by the OMG. NSAP address provided by the OMG.
(4) The TMGC sends the appropriate control message to the TMG. This (4) The TMGC sends the appropriate control message to the TMG. This
includes the session descriptor received from the OMG. This includes the session descriptor received from the OMG. This
descriptor contains the NSAP address of the OMG. descriptor contains the NSAP address of the OMG.
(5) The TMG acknowledges the control message from the TMGC. Along with (5) The TMG acknowledges the control message from the TMGC. Along with
the acknowledgement, it provides an SDP descriptor with a locally the acknowledgement, it provides an SDP descriptor with a locally
assigned eecid. assigned eecid.
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v=0 v=0
o=- 2873397714 0 ATM NSAP o=- 2873397714 0 ATM NSAP
47.0091.8100.0000.0040.2A74.EB03.0020.4421.2A04.00 47.0091.8100.0000.0040.2A74.EB03.0020.4421.2A04.00
s=- s=-
c=ATM NSAP c=ATM NSAP
47.0091.8100.0000.0040.2A74.EB03.0020.4421.2A04.00 47.0091.8100.0000.0040.2A74.EB03.0020.4421.2A04.00
t=0 0 t=0 0
m=audio $ AAL2/ITU 8 m=audio $ AAL2/ITU 8
a=eecid:B3D58E32 a=eecid:B3D58E32
skipping to change at line 2985 skipping to change at line 3069
(8) The OMG acknowledges the control message from the OMGC. (8) The OMG acknowledges the control message from the OMGC.
(9) The OMG sends an SVC set-up message to the TMG. Within the GIT (9) The OMG sends an SVC set-up message to the TMG. Within the GIT
information element, it includes eecid (B3D58E32) received from information element, it includes eecid (B3D58E32) received from
the TMG. the TMG.
(10)The TMG uses the eecid to correlate the SVC set-up request with the (10)The TMG uses the eecid to correlate the SVC set-up request with the
service-level control message received before from the TMGC. service-level control message received before from the TMGC.
Rajesh Kumar, Mohamed Mostafa. 51
(11)The TMG returns an SVC connect message to the OMG. On receiving (11)The TMG returns an SVC connect message to the OMG. On receiving
this message, the OMG sends an event notification to the OMGC this message, the OMG sends an event notification to the OMGC
indicating successful SVC set-up. indicating successful SVC set-up.
Note that, for this example, the "v=", "o=", "s=" and "t=" lines can be Note that, for this example, the "v=", "o=", "s=" and "t=" lines can be
omitted in the Megaco context. omitted in the Megaco context.
Rajesh Kumar, Mohamed Mostafa. 49
6.0 List of Parameters with Representations 6.0 List of Parameters with Representations
This section provides a list of the parameters used in this document, This section provides a list of the parameters used in this document,
and the formats used to represent them in SDP descriptions. In general, a and the formats used to represent them in SDP descriptions. In general, a
"-" value can be used for any field that is not specified, is inapplicable "-" value can be used for any field that is not specified, is inapplicable
or is implied. or is implied.
PARAMETER MEANING REPRESENTATION PARAMETER MEANING REPRESENTATION
<username> User name Constant "-" <username> User name Constant "-"
<sessionID> Session ID Up to 32 decimal or <sessionID> Session ID Up to 32 decimal or
hex digits hex digits
<version> Version of "0" or 10 decimal digits <version> Version of "0" or 10 decimal digits
SDP descriptor SDP descriptor
<networkType> Network type Constant "ATM" <networkType> Network type Constant "ATM" for ATM transport
<ATMaddressType> ATM address type String values: <addressType> Address type String values:
"NSAP", "E164", "GWID", "NSAP", "E164", "GWID",
"ALIAS" "ALIAS"
<ATMaddress> ATM address "NSAP": 40 hex digits, dotted <address> Address "NSAP": 40 hex digits, dotted
"E164": up to 15 decimal digits "E164": up to 15 decimal digits
"GWID": up to 32 characters "GWID": up to 32 characters
"ALIAS": up to 32 characters "ALIAS": up to 32 characters
<sessionName> Session name Constant "-" <sessionName> Session name Constant "-"
<startTime> Session start "0" or 10 decimal digits <startTime> Session start "0" or 10 decimal digits
time time
<stopTime> Session stop Constant "0" <stopTime> Session stop Constant "0"
skipping to change at line 3047 skipping to change at line 3131
<bcg> Bearer Connection Decimal or hex equivalent <bcg> Bearer Connection Decimal or hex equivalent
Group of 8 bits Group of 8 bits
<ex_bcg> Explicit "BCG-" prefixed to <bcg> <ex_bcg> Explicit "BCG-" prefixed to <bcg>
representation representation
of <bcg> of <bcg>
<portId> Port ID Hex number of up to 32 digits <portId> Port ID Hex number of up to 32 digits
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<ex_portId> Explicit "PORT-" prefixed to <portId> <ex_portId> Explicit "PORT-" prefixed to <portId>
representation representation
of <portId> of <portId>
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<vpi> Virtual Path Decimal or hex equivalent <vpi> Virtual Path Decimal or hex equivalent
Identifier of 8 or 12 bits Identifier of 8 or 12 bits
<ex_vpi> Explicit "VPI-" prefixed to <vpi> <ex_vpi> Explicit "VPI-" prefixed to <vpi>
representation representation
of <vpi> of <vpi>
<vci> Virtual Circuit Decimal or hex equivalent <vci> Virtual Circuit Decimal or hex equivalent
Identifier of 16 bits Identifier of 16 bits
skipping to change at line 3106 skipping to change at line 3190
"AAL2", "AAL3/4", "AAL2", "AAL3/4",
"AAL5", "USER_DEFINED_AAL" "AAL5", "USER_DEFINED_AAL"
<silenceSuppEnable> Silence suppression String values: <silenceSuppEnable> Silence suppression String values:
Enable "on", "off" Enable "on", "off"
<silenceTimer> Kick-in timer Decimal or hex representation <silenceTimer> Kick-in timer Decimal or hex representation
for silence of 16-bit field for silence of 16-bit field
suppression suppression
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<suppPref> Preferred Silence String values: <suppPref> Preferred Silence String values:
Suppression Method "standard", "custom" Suppression Method "standard", "custom"
<sidUse> SID Use String values: <sidUse> SID Use String values:
Method "No SID", "Fixed Noise", Method "No SID", "Fixed Noise",
"Sampled Noise" "Sampled Noise"
<fxnslevel> Fixed Noise Decimal or hex representation <fxnslevel> Fixed Noise Decimal or hex representation
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Level of a 7-bit field Level of a 7-bit field
<ecanEnable> Enable Echo String values: <ecanEnable> Enable Echo String values:
Cancellation "on", "off" Cancellation "on", "off"
<ecanType> Type of Echo String values: <ecanType> Type of Echo String values:
Cancellation "G165", "G168" Cancellation "G165", "G168"
<gcEnable> Enable Gain String values: <gcEnable> Enable Gain String values:
Control "on", "off" Control "on", "off"
skipping to change at line 3167 skipping to change at line 3251
subtype subtype
<qosClass> QoS Class Decimal integer 0-5 <qosClass> QoS Class Decimal integer 0-5
<bcob> Broadband Bearer Decimal or hex representation <bcob> Broadband Bearer Decimal or hex representation
Class of 5-bit field Class of 5-bit field
<stc> Susceptibility Decimal equivalent of <stc> Susceptibility Decimal equivalent of
to clipping a 2-bit field to clipping a 2-bit field
Rajesh Kumar, Mohamed Mostafa. 54
<upcc> User plane Decimal equivalent of <upcc> User plane Decimal equivalent of
connection a 2-bit field connection a 2-bit field
configuration configuration
<cdvType> CDV type String values: <cdvType> CDV type String values:
"PP", "2P" "PP", "2P"
<acdv> Acceptable CDV Decimal equivalent <acdv> Acceptable CDV Decimal equivalent
Rajesh Kumar, Mohamed Mostafa. 52
of 24-bit field of 24-bit field
<ccdv> Cumulative CDV Decimal equivalent <ccdv> Cumulative CDV Decimal equivalent
of 24-bit field of 24-bit field
<actd> Acceptable CTD Decimal equivalent <actd> Acceptable CTD Decimal equivalent
of 16-bit field of 16-bit field
<cctd> Cumulative CTD Decimal equivalent <cctd> Cumulative CTD Decimal equivalent
of 16-bit field of 16-bit field
skipping to change at line 3228 skipping to change at line 3312
<nrm> NRM Decimal/hex equivalent <nrm> NRM Decimal/hex equivalent
of 3 bit field of 3 bit field
<trm> TRM - ditto- <trm> TRM - ditto-
<cdf> CDF -ditto- <cdf> CDF -ditto-
<adtf> ADTF Decimal/Hex equivalent <adtf> ADTF Decimal/Hex equivalent
of 10 bit field of 10 bit field
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<clkrec> Clock Recovery String values: <clkrec> Clock Recovery String values:
Method "NULL", "SRTS", Method "NULL", "SRTS",
"ADAPTIVE" "ADAPTIVE"
<fecEnable> Forward Error String values: <fecEnable> Forward Error String values:
Correction Enable "NULL", "LOSS_SENSITIVE" Correction Enable "NULL", "LOSS_SENSITIVE"
"DELAY_SENSITIVE" "DELAY_SENSITIVE"
<partialFill> Partial Fill Decimal integer 1-48 <partialFill> Partial Fill Decimal integer 1-48
or hex equivalent or hex equivalent
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<bearerType> Bearer Type String Values: <bearerType> Bearer Type String Values:
"PVC", "SVC", "CID" "PVC", "SVC", "CID"
<localInititiation> Local Initiation String values: <localInititiation> Local Initiation String values:
"on", "off" "on", "off"
<structureEnable> Structure Present String values: <structureEnable> Structure Present String values:
"on", "off" "on", "off"
<blksz> Block Size Decimal or hexadecimal <blksz> Block Size Decimal or hexadecimal
skipping to change at line 3291 skipping to change at line 3375
<bsssar> Maximum SSSAR-SDU Decimal or hex <bsssar> Maximum SSSAR-SDU Decimal or hex
size, backward equivalent of 16-bit size, backward equivalent of 16-bit
direction field direction field
<sap> Service Access String values: <sap> Service Access String values:
Point "AUDIO", "MULTIRATE" Point "AUDIO", "MULTIRATE"
<circuitMode> Circuit Mode String values: <circuitMode> Circuit Mode String values:
Enable "on", "off" Enable "on", "off"
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<frameMode> Frame Mode String values: <frameMode> Frame Mode String values:
Enable "on", "off" Enable "on", "off"
<faxDemod> Fax Demodulation String values: <faxDemod> Fax Demodulation String values:
Enable "on", "off" Enable "on", "off"
<cas> Enable CAS transport String values: <cas> Enable CAS transport String values:
via Type 3 packets "on", "off" via Type 3 packets "on", "off"
Rajesh Kumar, Mohamed Mostafa. 54
<dtmf> Enable DTMF transport String values: <dtmf> Enable DTMF transport String values:
via Type 3 packets "on", "off" via Type 3 packets "on", "off"
<mfall> Enable MF transport String values: <mfall> Enable MF transport String values:
via Type 3 packets "on", "off" via Type 3 packets "on", "off"
<mfr1> Enable MF (R1) String values: <mfr1> Enable MF (R1) String values:
transport via "on", "off" transport via "on", "off"
Type 3 packets Type 3 packets
skipping to change at line 3354 skipping to change at line 3438
connection scope equivalent of connection scope equivalent of
selection IE 2 bits selection IE 2 bits
Definition: UNI 4.0 [5] Definition: UNI 4.0 [5]
<conScpTyp> Type of connection scope Decimal or hex <conScpTyp> Type of connection scope Decimal or hex
Definition: UNI 4.0 [5] equivalent of 4 bits Definition: UNI 4.0 [5] equivalent of 4 bits
<conScpSel> Connection scope selection Decimal or hex equivalent <conScpSel> Connection scope selection Decimal or hex equivalent
Definition: UNI 4.0 [5] of 8 bits Definition: UNI 4.0 [5] of 8 bits
Rajesh Kumar, Mohamed Mostafa. 57
<cacheEnable> Enable SVC caching String values: "on", "off" <cacheEnable> Enable SVC caching String values: "on", "off"
<cacheTimer> Timer for cached SVC Decimal or hex equivalent <cacheTimer> Timer for cached SVC Decimal or hex equivalent
deletion of 32-bit field deletion of 32-bit field
<rtcpPortNum> RTCP port number for Odd decimal in range 1,024 to <rtcpPortNum> RTCP port number for Odd decimal in range 1,024 to
H.323 Annex C applications 65,535. H.323 Annex C applications 65,535.
Preferred: Odd number in Preferred: Odd number in
Rajesh Kumar, Mohamed Mostafa. 55
the range 49,152 to 65,535 the range 49,152 to 65,535
<rtcpIPaddr> IP address for receipt Dotted decimal, 7-15 chars <rtcpIPaddr> IP address for receipt Dotted decimal, 7-15 chars
of RTCP packets of RTCP packets
<chainPointer> Chain pointer String values: "NEXT", <chainPointer> Chain pointer String values: "NEXT",
"PREVIOUS", "NULL" "PREVIOUS", "NULL"
7.0 Examples of ATM session descriptions using SDP 7.0 Examples of ATM session descriptions using SDP
An example of a complete AAL1 session description in SDP is: An example of a complete AAL1 session description in SDP is:
skipping to change at line 3404 skipping to change at line 3488
t=0 0 t=0 0
m=audio $ AAL2/ITU 8 AAL2/custom 100 AAL2/ITU 1 m=audio $ AAL2/ITU 8 AAL2/custom 100 AAL2/ITU 1
a=eecid:B3E32 a=eecid:B3E32
The AAL2 session descriptor below is the same as the one above The AAL2 session descriptor below is the same as the one above
except that it states an explicit preference for a voice codec, a except that it states an explicit preference for a voice codec, a
voiceband data codec and a voiceband fax codec. Further, it defines voiceband data codec and a voiceband fax codec. Further, it defines
the profile AAL2/custom 100 rather than assume that the far-end is the profile AAL2/custom 100 rather than assume that the far-end is
cognizant of the elements of this profile. cognizant of the elements of this profile.
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v=0 v=0
o=- A3C47F21456789F0 0 ATM NSAP o=- A3C47F21456789F0 0 ATM NSAP
47.0091.8100.0000.0060.3e64.fd01.0060.3e64.fd01.00 47.0091.8100.0000.0060.3e64.fd01.0060.3e64.fd01.00
s=- s=-
c=ATM NSAP c=ATM NSAP
47.0091.8100.0000.0060.3e64.fd01.0060.3e64.fd01.00 47.0091.8100.0000.0060.3e64.fd01.0060.3e64.fd01.00
t=0 0 t=0 0
m=audio $ AAL2/ITU 8 AAL2/custom 100 AAL2/ITU 1 m=audio $ AAL2/ITU 8 AAL2/custom 100 AAL2/ITU 1
a=eecid:B3E32 a=eecid:B3E32
a=profileDesc:AAL2/custom 100 0-7 PCMG 40 5 0-7 SIDG 1 a=profileDesc:AAL2/custom 100 0-7 PCMG 40 5 0-7 SIDG 1
skipping to change at line 3418 skipping to change at line 3503
c=ATM NSAP c=ATM NSAP
47.0091.8100.0000.0060.3e64.fd01.0060.3e64.fd01.00 47.0091.8100.0000.0060.3e64.fd01.0060.3e64.fd01.00
t=0 0 t=0 0
m=audio $ AAL2/ITU 8 AAL2/custom 100 AAL2/ITU 1 m=audio $ AAL2/ITU 8 AAL2/custom 100 AAL2/ITU 1
a=eecid:B3E32 a=eecid:B3E32
a=profileDesc:AAL2/custom 100 0-7 PCMG 40 5 0-7 SIDG 1 a=profileDesc:AAL2/custom 100 0-7 PCMG 40 5 0-7 SIDG 1
5 8-15 G726-32 40 10 8-15 SIDG 1 5 5 8-15 G726-32 40 10 8-15 SIDG 1 5
a=vsel:G726-32 40 10 a=vsel:G726-32 40 10
a=dsel:off PCMU - - a=dsel:off PCMU - -
a=fsel:G726-32 40 10 a=fsel:G726-32 40 10
An example of an SDP session descriptor for an AAL5 switched virtual circuit An example of an SDP session descriptor for an AAL5 switched virtual circuit
for delivering MPEG-2 video: for delivering MPEG-2 video:
v=0 v=0
o=- A3C47F21456789F0 0 ATM NSAP o=- A3C47F21456789F0 0 ATM NSAP
47.0091.8100.0000.0060.3e64.fd01.0060.3e64.fd01.00 47.0091.8100.0000.0060.3e64.fd01.0060.3e64.fd01.00
Rajesh Kumar, Mohamed Mostafa. 56
s=- s=-
c=ATM NSAP 47.0091.8100.0000.0060.3e64.fd01.0060.3e64.fd01.00 c=ATM NSAP 47.0091.8100.0000.0060.3e64.fd01.0060.3e64.fd01.00
t=0 0 t=0 0
m=video $ AAL5/ITU 33 m=video $ AAL5/ITU 33
a=eecid:B3E32 a=eecid:B3E32
a=aalType:AAL5 a=aalType:AAL5
a=bearerType:SVC on a=bearerType:SVC on
a=atmFtrfcDesc:0+1 7816 - - - - - off - a=atmFtrfcDesc:0+1 7816 - - - - - off -
a=atmBtrfcDesc:0+1 0 - - - - - on - a=atmBtrfcDesc:0+1 0 - - - - - on -
a=fcpsSDUsize:20680 a=fcpsSDUsize:20680
skipping to change at line 3465 skipping to change at line 3549
The following encoding names in Table 2 can refer to data as well The following encoding names in Table 2 can refer to data as well
as audio media: X-CCD and X-CCD-CAS in Table 2. as audio media: X-CCD and X-CCD-CAS in Table 2.
The following encoding names in Table 2 refer to data media: The following encoding names in Table 2 refer to data media:
X-FXDMOD-3 in Table 2. X-FXDMOD-3 in Table 2.
In the AAL1 context, X-CCD and X-CCD-CAS can be represented as In the AAL1 context, X-CCD and X-CCD-CAS can be represented as
"audio" codecs that are dynamically mapped into payload types. This "audio" codecs that are dynamically mapped into payload types. This
is done through the 'atmmap' attribute, as described earlier. For is done through the 'atmmap' attribute, as described earlier. For
example: example:
Rajesh Kumar, Mohamed Mostafa. 59
m=audio VCCI-27 AAL1/AVP 98 m=audio VCCI-27 AAL1/AVP 98
a=atmmap:98 X-CCD a=atmmap:98 X-CCD
implies that AAL1 VCCI=27 is used for n x 64 transmission. implies that AAL1 VCCI=27 is used for n x 64 transmission.
Currently, AAL1 in unsuitable for transmitting demodulated facsimile Currently, AAL1 in unsuitable for transmitting demodulated facsimile
because it lacks the bearer plane mechanisms (equivalent to AAL2 because it lacks the bearer plane mechanisms (equivalent to AAL2
type 3 messages) for transmitting control information. type 3 messages) for transmitting control information.
In the AAL2 context, these "codecs" can be assigned profile types and In the AAL2 context, these "codecs" can be assigned profile types and
skipping to change at line 3486 skipping to change at line 3572
profile tables as described in ITU I.366.2 for these "codecs", it profile tables as described in ITU I.366.2 for these "codecs", it
is preferable to adopt the common AAL2 profile convention in their is preferable to adopt the common AAL2 profile convention in their
case. An example AAL2 profile mapping for these could be as follows: case. An example AAL2 profile mapping for these could be as follows:
PROFILE TYPE PROFILE NUMBER "CODEC" (ONLY ONE) PROFILE TYPE PROFILE NUMBER "CODEC" (ONLY ONE)
"custom" 200 X-CCD "custom" 200 X-CCD
"custom" 201 X-FXDMOD-3 "custom" 201 X-FXDMOD-3
The profile does not identify the number of subchannels ('n' in nx64). The profile does not identify the number of subchannels ('n' in nx64).
This is known by other means such as the 'sbc' media attribute line. This is known by other means such as the 'sbc' media attribute line.
Rajesh Kumar, Mohamed Mostafa. 57
Currently, there is no definition of n x 64 trunking with CAS for AAL2. Currently, there is no definition of n x 64 trunking with CAS for AAL2.
For example, the media information line: For example, the media information line:
m=audio $ AAL2/custom 200 m=audio $ AAL2/custom 200
a=sbc:6 a=sbc:6
implies a 384 kbps n x 64 circuit using AAL2 adaptation. implies a 384 kbps n x 64 circuit using AAL2 adaptation.
In the case of fax demodulation and remodulation (ITU I.366.2), In the case of fax demodulation and remodulation (ITU I.366.2),
parameters such as information type, image data size and control parameters such as information type, image data size and control
skipping to change at line 3528 skipping to change at line 3612
premises. SDP relies on the security mechanisms of the encapsulating premises. SDP relies on the security mechanisms of the encapsulating
protocol or layers below the encapsulating protocol. Examples of protocol or layers below the encapsulating protocol. Examples of
encapsulating protocols are the Session Initiation Protocol (SIP), encapsulating protocols are the Session Initiation Protocol (SIP),
MGCP and Multimedia Gateway Control Protocol (MEGACO). No additional MGCP and Multimedia Gateway Control Protocol (MEGACO). No additional
security mechanisms are needed. SIP, MGCP and MEGACO security mechanisms are needed. SIP, MGCP and MEGACO
can use IPSec authentication as described in RFC1826 [Ref. can use IPSec authentication as described in RFC1826 [Ref.
27]. IPSec encryption can be optionally used with authentication to 27]. IPSec encryption can be optionally used with authentication to
provide an additional, potentially more expensive level of security. provide an additional, potentially more expensive level of security.
IPSec security associations can be made between equipment located in IPSec security associations can be made between equipment located in
untrusted areas and equipment located in trusted areas through untrusted areas and equipment located in trusted areas through
Rajesh Kumar, Mohamed Mostafa. 60
configured shared secrets or the use of a certificate authority. configured shared secrets or the use of a certificate authority.
10. ATM SDP Grammar 10. ATM SDP Grammar
This appendix provides an Augmented BNF (ABNF) grammar for the ATM This appendix provides an Augmented BNF (ABNF) grammar for the ATM
conventions for SDP. ABNF is defined in rfc2234. This is not a complete ABNF conventions for SDP. ABNF is defined in rfc2234. This is not a complete ABNF
description of SDP. Readers are referred to [1] for an ABNF description description of SDP. Readers are referred to [1] for an ABNF description
of the SDP base line protocol, and to rfc2848, rfc2543, rfc2045 and rfc2326 of the SDP base line protocol, and to rfc2848, rfc2543, rfc2045 and rfc2326
for application-specific conventions for SDP use. for application-specific conventions for SDP use.
skipping to change at line 3549 skipping to change at line 3635
safe = alpha-numeric / "'" / "-" / "." / "/" / ":" / "?" / DQUOTE / "#" / safe = alpha-numeric / "'" / "-" / "." / "/" / ":" / "?" / DQUOTE / "#" /
"$" / "&" / "*" / ";" / "=" / "@" / "[" / "]" / "^" / "_" / "`" / "{" / "$" / "&" / "*" / ";" / "=" / "@" / "[" / "]" / "^" / "_" / "`" / "{" /
"|" / "}" / "+" / "~" "|" / "}" / "+" / "~"
DQUOTE = %x22 ; double quote DQUOTE = %x22 ; double quote
alpha-numeric = ALPHA / DIGIT alpha-numeric = ALPHA / DIGIT
ALPHA = "a" / "b" / "c" / "d" / "e" / "f" / "g" / "h" / "i" / "j" / "k" / ALPHA = "a" / "b" / "c" / "d" / "e" / "f" / "g" / "h" / "i" / "j" / "k" /
"l" / "m" / "n" / "o" / "p" / "q" / "r" / "s" / "t" / "u" / "v" / "l" / "m" / "n" / "o" / "p" / "q" / "r" / "s" / "t" / "u" / "v" /
"w" / "x" / "y" / "z" / "w" / "x" / "y" / "z" /
"A" / "B" / "C" / "D" / "E" / "F" / "G" / "H" / "I" / "J" / "K" / "A" / "B" / "C" / "D" / "E" / "F" / "G" / "H" / "I" / "J" / "K" /
Rajesh Kumar, Mohamed Mostafa. 58
"L" / "M" / "N" / "O" / "P" / "Q" / "R" / "S" / "T" / "U" / "V" / "L" / "M" / "N" / "O" / "P" / "Q" / "R" / "S" / "T" / "U" / "V" /
"W" / "X" / "Y" / "Z" "W" / "X" / "Y" / "Z"
DIGIT = "0" / POS-DIGIT DIGIT = "0" / POS-DIGIT
POS-DIGIT = "1" / "2" / "3" / "4" / "5" / "6" / "7" / "8" / "9" POS-DIGIT = "1" / "2" / "3" / "4" / "5" / "6" / "7" / "8" / "9"
hex-prefix = "0" ("x" / "X") hex-prefix = "0" ("x" / "X")
HEXDIG = DIGIT / "a" / "b" / "c" / "d" / "e" / "f" / HEXDIG = DIGIT / "a" / "b" / "c" / "d" / "e" / "f" /
"A" / "B" / "C" / "D" / "E" / "F" "A" / "B" / "C" / "D" / "E" / "F"
space = %d32 space = %d32
EOL = (CR / LF / CRLF) ; as per Megaco RFC EOL = (CR / LF / CRLF) ; as per Megaco RFC
CR = %d13 CR = %d13
skipping to change at line 3589 skipping to change at line 3673
generic-U16-or-null = generic-U16 / "-" generic-U16-or-null = generic-U16 / "-"
generic-U32-or-null = generic-U32 / "-" generic-U32-or-null = generic-U32 / "-"
decimal-U8-or-null = decimal-uchar / "-" decimal-U8-or-null = decimal-uchar / "-"
decimal-U12-or-null = 1*4(DIGIT) / "-" decimal-U12-or-null = 1*4(DIGIT) / "-"
decimal-U16-or-null = 1*5(DIGIT) / "-" decimal-U16-or-null = 1*5(DIGIT) / "-"
decimal-U32-or-null = 1*10(DIGIT) / "-" decimal-U32-or-null = 1*10(DIGIT) / "-"
on-off-or-null = "on" / "off" / "-" on-off-or-null = "on" / "off" / "-"
; ABNF definition of SDP with ATM conventions ; ABNF definition of SDP with ATM conventions
Rajesh Kumar, Mohamed Mostafa. 61
SDP-infoset = 1*(announcement)announcement = proto-version origin-field SDP-infoset = 1*(announcement)announcement = proto-version origin-field
session-name-field session-name-field information-field uri-field email-fields phone-fields
information-field uri-field email-fields phone-fields connection-field connection-field bandwidth-fields time-fields key-field attribute-fields media-
bandwidth-fields time-fields key-field attribute-fields media-descriptions descriptions
proto-version = ["v=" 1*4(DIGIT) EOL] ; use "v=0" for ATM SDP proto-version = ["v=" 1*4(DIGIT) EOL] ; use "v=0" for ATM SDP
origin-field = ["o=" username space sess-id space sess-version space origin-field = ["o=" username space sess-id space sess-version space
net-type-addr EOL] net-type-addr EOL]
username = 1* safe ; for ATM use "-" username = 1* safe ; for ATM use "-"
sess-id = (1*32 DIGIT) / (hex-prefix 1*32 HEXDIG) sess-id = (1*32 DIGIT) / (hex-prefix 1*32 HEXDIG)
sess-version = (1*10 DIGIT) / (hex-prefix 1*8 HEXDIG) sess-version = (1*10 DIGIT) / (hex-prefix 1*8 HEXDIG)
net-type-addr= ip-net-type-addr/ atm-net-type-addr/ tn-net-type-addr net-type-addr= nettype space addrtype-addr
; ip-net-type-addr per rfc2327
; tn-net-type-addr per rfc2848
Rajesh Kumar, Mohamed Mostafa. 59 netttype = "ATM" / "IN" / "TN" / "-" / "$"
; Other nettype values may be defined in the future in other documents
; Validity of nettype and addrtype-addr combination to be checked at
; application level, not protocol syntax level
addrtype-addr = atm-addrtype-addr / ip-addrtype-addr / tn-addrtype-addr
; ip-addrtype-addr per rfc2327
; tn-addrtype-addr per rfc2848
; ATM address definition ; ATM address definition
atm-net-type-addr= "ATM" space atm-type-addr atm-addrtype-addr = atm-nsap-addr / atm-e164-addr / atm-alias-addr
atm-type-addr = atm-nsap-addr / atm-e164-addr / atm-alias-addr /
"-" space "-" /"$" space "$"
atm-nsap-addr = "NSAP" space (nsap-addr / "-" / "$") atm-nsap-addr = ("NSAP" / "-" / "$") space (nsap-addr / "-" / "$")
atm-e164-addr = "E164" space (e164-addr / "-" / "$") atm-e164-addr = ("E164" / "-" / "$") space (e164-addr / "-" / "$")
atm-alias-addr = ("GWID" / "ALIAS") space (alias-addr / "-" / "$") atm-alias-addr = ("GWID" / "ALIAS" / "-" / "$") space (alias-addr / "-" / "$")
nsap-addr = 2(HEXDIG) "." 9(4(HEXDIG) ".") 2(HEXDIG) nsap-addr = 2(HEXDIG) "." 9(4(HEXDIG) ".") 2(HEXDIG)
e164-addr = 1*15 (DIGIT) e164-addr = 1*15 (DIGIT)
alias-addr = 1*32(alpha-numeric / "-" / "." / "_") alias-addr = 1*32(alpha-numeric / "-" / "." / "_")
session-name-field = ["s=" text EOL] ; for ATM use "s=-" session-name-field = ["s=" text EOL] ; for ATM use "s=-"
text = byte-string text = byte-string
byte-string = 1*(byte-string-char) ; definition per rfc2327 byte-string = 1*(byte-string-char) ; definition per rfc2327
byte-string-char = %x01-09/ %x0B/ %x0C/ %x0E-FF ; all ASCII except NUL, CR & LF byte-string-char = %x01-09/ %x0B/ %x0C/ %x0E-FF ; all ASCII except NUL, CR & LF
; Definitions of information-field, uri-field, email-fields, ; Definitions of information-field, uri-field, email-fields,
; phone-fields per rfc2327. These fields are omitted in ; phone-fields per rfc2327. These fields are omitted in
; ATM SDP descriptions. If received, they are ignored in the ATM context ; ATM SDP descriptions. If received, they are ignored in the ATM context
connection-field = ["c=" c-net-type-addr] ; required, not optional, in ATM connection-field = ["c=" c-net-type-addr]
c-net-type-addr = c-ip-net-type-addr / atm-net-type-addr / tn-net-type-addr ; connection-field required, not optional, in ATM
; c-ip-net-type-addr per rfc2327
; atm-net-type-addr defined above c-net-type-addr = nettype space c-addrtype-addr
; tn-net-type-addr per rfc2848 c-addrtype-addr = atm-addrtype-addr / c-ip-addrtype-addr / tn-addrtype-addr
; atm-addrtype-addr defined above
; c-ip-addrtype-addr per rfc2327
; difference in address usage between 'o' and 'c' lines per rfc2327
Rajesh Kumar, Mohamed Mostafa. 62
; tn-addrtype-addr per rfc2848
bandwidth-fields = *("b=" bwtype ":" bandwidth EOL) bandwidth-fields = *("b=" bwtype ":" bandwidth EOL)
bwtype = 1*(alpha-numeric) bwtype = 1*(alpha-numeric)
bandwidth = 1*(DIGIT) bandwidth = 1*(DIGIT)
time-fields = *( "t=" start-time space stop-time *(EOL repeat-fields) EOL) time-fields = *( "t=" start-time space stop-time *(EOL repeat-fields) EOL)
[zone-adjustments EOL] [zone-adjustments EOL]
start-time = time / "0" start-time = time / "0"
stop-time = time / "0" ; always "0" in ATM stop-time = time / "0" ; always "0" in ATM
time = POS-DIGIT 9*(DIGIT) ; same as rfc2327 time = POS-DIGIT 9*(DIGIT) ; same as rfc2327
skipping to change at line 3663 skipping to change at line 3761
attribute-fields = *("a=" attribute EOL) attribute-fields = *("a=" attribute EOL)
; SDP descriptors for ATM do not have session-level media attribute lines ; SDP descriptors for ATM do not have session-level media attribute lines
; If these are provided, they should be ignored. ; If these are provided, they should be ignored.
media-descriptions = *(media-description) media-descriptions = *(media-description)
media-description = media-field information-field *(connection-field) media-description = media-field information-field *(connection-field)
bandwidth-fields key-field attribute-fields bandwidth-fields key-field attribute-fields
Rajesh Kumar, Mohamed Mostafa. 60
; Definitions of information-field per rfc2327. This fields are omitted in ; Definitions of information-field per rfc2327. This fields are omitted in
; ATM SDP descriptions. If received, they are ignored in the ATM context ; ATM SDP descriptions. If received, they are ignored in the ATM context
; ;
; In ATM, the connection-field is used in media-description to indicate ; In ATM, the connection-field is used in media-description to indicate
; the IP address associated with the RTCP control protocol in H.323.C ; the IP address associated with the RTCP control protocol in H.323.C
; applications. In this case, the connection field is per the rfc2327 ; applications. In this case, the connection field is per the rfc2327
; definition for IP v4-based connections. Otherwise, it is not used in ; definition for IP v4-based connections. Otherwise, it is not used in
; media-description. If received as part of media-description, ; media-description. If received as part of media-description,
; it is ignored. ; it is ignored.
; ;
skipping to change at line 3686 skipping to change at line 3782
: Definition of optional key-field as in rfc2327 : Definition of optional key-field as in rfc2327
media-field = rfc2327-media-field / rfc2848-media-field / atm-media-field media-field = rfc2327-media-field / rfc2848-media-field / atm-media-field
; rfc2327-media-field and rfc2848-media-field defined in those rfc's ; rfc2327-media-field and rfc2848-media-field defined in those rfc's
atm-media-field = "m=" media space vcId space transport-fmts EOL atm-media-field = "m=" media space vcId space transport-fmts EOL
; superset of rfc2327 definition ; superset of rfc2327 definition
media = "audio" / "video" / "data" / "application" / "control" / media = "audio" / "video" / "data" / "application" / "control" /
1*(alpha-numeric) 1*(alpha-numeric)
vcId = "$" / ex-vcci / (ex-vcci "/" ex-cid) / vcId = "$" / "-" / ex-vcci / (ex-vcci "/" ex-cid) /
(atm-type-addr-m "/" ex-vcci) / (atm-type-addr-m "/" ex-vcci) /
(atm-type-addr-m "/" ex-vcci "/" ex-cid) / (atm-type-addr-m "/" ex-vcci "/" ex-cid) /
(ex-bcg "/" ex-vcci) / (ex-bcg "/" ex-vcci "/" ex-cid) (ex-bcg "/" ex-vcci) / (ex-bcg "/" ex-vcci "/" ex-cid)
(ex-portid "/" ex-vpi "/" ex-vci) / (ex-portid "/" ex-vpi "/" ex-vci) /
(ex-portid "/" ex-vpi "/" ex-vci "/" ex-cid) / (ex-portid "/" ex-vpi "/" ex-vci "/" ex-cid) /
(ex-bcg "/" ex-vpi "/" ex-vci) / (ex-bcg "/" ex-vpi "/" ex-vci) /
(ex-bcg "/" ex-vpi "/" ex-vci "/" ex-cid) / (ex-bcg "/" ex-vpi "/" ex-vci "/" ex-cid) /
(ex-vpci "/" ex-vci) / (ex-vpci "/" ex-vci) /
(ex-vpci "/" ex-vci "/" ex-cid) / (ex-vpci "/" ex-vci "/" ex-cid) /
Rajesh Kumar, Mohamed Mostafa. 63
(atm-type-addr-m "/" ex-vpci "/" ex-vci) / (atm-type-addr-m "/" ex-vpci "/" ex-vci) /
(atm-type-addr-m "/" ex-vpci "/" ex-vci "/" ex-cid) (atm-type-addr-m "/" ex-vpci "/" ex-vci "/" ex-cid)
atm-type-addr-m = atm-nsap-addr-m / atm-e164-addr-m / atm-alias-addr-m atm-type-addr-m = atm-nsap-addr-m / atm-e164-addr-m / atm-alias-addr-m
atm-nsap-addr-m = ["NSAP-"] (nsap-addr / "$") atm-nsap-addr-m = ["NSAP-"] (nsap-addr / "$")
atm-e164-addr-m = ["E164-"] (e164-addr / "$") atm-e164-addr-m = ["E164-"] (e164-addr / "$")
atm-alias-addr-m = ["GWID-" / "ALIAS-"] (alias-addr / "$") atm-alias-addr-m = ["GWID-" / "ALIAS-"] (alias-addr / "$")
; The -m at the end indicates use in the media field ; The -m at the end indicates use in the media field
; Wildcarding rules different from ATM address on 'o' and 'c' lines
ex-vcci = "VCCI-" vcci ex-vcci = "VCCI-" vcci
ex-cid = "CID-" cid ex-cid = "CID-" cid
ex-bcg = "BCG-" bcg ex-bcg = "BCG-" bcg
ex-portid = "PORT-" portid ex-portid = "PORT-" portid
ex-vpi = "VPI-" vpi ex-vpi = "VPI-" vpi
ex-vci = "VCI-" vci ex-vci = "VCI-" vci
ex-vpci = "VPCI-" vpci ex-vpci = "VPCI-" vpci
vcci = generic-U16 vcci = generic-U16
cid = generic-U8 cid = generic-U8
bcg = generic-U8 bcg = generic-U8
portid = 1*32 (HEXDIG) portid = 1*32 (HEXDIG)
vpi = generic-U12 vpi = generic-U12
vci = generic-U16 vci = generic-U16
vpci = generic-U16 vpci = generic-U16
transport-fmts = generic-transport-fmts / known-transport-fmts / "- -" transport-fmts = generic-transport-fmts / known-transport-fmts / "- -"
Rajesh Kumar, Mohamed Mostafa. 61
generic-transport-fmts = generic-transport 1*(space fmt) generic-transport-fmts = generic-transport 1*(space fmt)
generic-transport = 1*(alpha-numeric / "/") generic-transport = 1*(alpha-numeric / "/")
fmt = 1*(alpha-numeric) fmt = 1*(alpha-numeric)
known-transport-fmts = aal1-transport space aal1-fmt-list / known-transport-fmts = aal1-transport space aal1-fmt-list /
aal2-transport space aal2-fmt-list aal2-transport space aal2-fmt-list
*(space aal2-transport space aal2-fmt-list) / *(space aal2-transport space aal2-fmt-list) /
aal5-transport space aal5-fmt-list / aal5-transport space aal5-fmt-list /
rtp-transport space rtp-fmt-list / rtp-transport space rtp-fmt-list /
tn-proto space tn-fmt-list / tn-proto space tn-fmt-list /
skipping to change at line 3758 skipping to change at line 3854
rtp-transport = "RTP" "/" rtp-transport-list rtp-transport = "RTP" "/" rtp-transport-list
rtp-transport-list = "AVP" rtp-transport-list = "AVP"
aal1-fmt-list = (payload-type *(space payload-type)) / "-" aal1-fmt-list = (payload-type *(space payload-type)) / "-"
payload-type = decimal-uchar payload-type = decimal-uchar
aal5-fmt-list = aal1-fmt-list aal5-fmt-list = aal1-fmt-list
rtp-fmt-list = aal1-fmt-list rtp-fmt-list = aal1-fmt-list
aal2-fmt-list = (profile *(space profile)) / "-" aal2-fmt-list = (profile *(space profile)) / "-"
profile = decimal-uchar profile = decimal-uchar
Rajesh Kumar, Mohamed Mostafa. 64
attribute-fields = *("a=" attribute EOL) attribute-fields = *("a=" attribute EOL)
attribute = known-attribute / (generic-att-field ":" att-value) / attribute = known-attribute / (generic-att-field ":" att-value) /
generic-att-field generic-att-field
generic-att-field = 1*(alpha-numeric) generic-att-field = 1*(alpha-numeric)
att-value = byte-string att-value = byte-string
known-attribute = atm-attribute / PIMT-attribute / rfc2327-attribute known-attribute = atm-attribute / PIMT-attribute / rfc2327-attribute
; PINT-attribute as defined in rfc2848 ; PINT-attribute as defined in rfc2848
; rfc2327 attribute as defined in that rfc ; rfc2327 attribute as defined in that rfc
atm-attribute = atm-attribute =
skipping to change at line 3783 skipping to change at line 3881
"ecanf" ":" ecanEnable space ecanType / "ecanf" ":" ecanEnable space ecanType /
"ecanb" ":" ecanEnable space ecanType / "ecanb" ":" ecanEnable space ecanType /
"gcf" ":" gcEnable space gcLvl / "gcf" ":" gcEnable space gcLvl /
"gcb" ":" gcEnable space gcLvl / "gcb" ":" gcEnable space gcLvl /
"profileDesc" ":" aal2-transport space profile space "profileDesc" ":" aal2-transport space profile space
1*(profile-row) / 1*(profile-row) /
"vsel" ":" 1*(encoding-name space packet-length space "vsel" ":" 1*(encoding-name space packet-length space
packet-time space) / packet-time space) /
"dsel" ":" fxIncl space "dsel" ":" fxIncl space
Rajesh Kumar, Mohamed Mostafa. 62
1*(encoding-name space packet-length space 1*(encoding-name space packet-length space
packet-time space) / packet-time space) /
"fsel" ":" 1*(encoding-name space packet-length space "fsel" ":" 1*(encoding-name space packet-length space
packet-time space) / packet-time space) /
"capability" ":" (asc / atc / 1*(alpha-numeric)) space capab-subtype / "capability" ":" (asc / atc / 1*(alpha-numeric)) space capab-subtype /
"qosclass" ":" qosclass / "qosclass" ":" qosclass /
"bcob" ":" bcob / "bcob" ":" bcob /
"stc" ":" stc / "stc" ":" stc /
"upcc" ":" upcc / "upcc" ":" upcc /
"atmQOSfparms" ":" cdvType space acdv space ccdv space actd space cctd "atmQOSfparms" ":" cdvType space acdv space ccdv space actd space cctd
skipping to change at line 3820 skipping to change at line 3916
"prtfl" ":" partialFill / "prtfl" ":" partialFill /
"bearertype" ":" bearerType space localInitiation / "bearertype" ":" bearerType space localInitiation /
"structure" ":" structureEnable space blksz / "structure" ":" structureEnable space blksz /
"sbc" ":" sbc / "sbc" ":" sbc /
"fcpsSDUsize" ":" cpcs / "fcpsSDUsize" ":" cpcs /
"bcpsSDUsize" ":" cpcs / "bcpsSDUsize" ":" cpcs /
"aal2CPS" ":" cidCount space timerCU / "aal2CPS" ":" cidCount space timerCU /
"aal2sscs3661" ":" adt space ted space fsssar space bsssar / "aal2sscs3661" ":" adt space ted space fsssar space bsssar /
"aal2sscs3662" ":" sap space circuitMode space frameMode space faxDemod "aal2sscs3662" ":" sap space circuitMode space frameMode space faxDemod
space cas space dtmf space mfall space mfr1 space cas space dtmf space mfall space mfr1
Rajesh Kumar, Mohamed Mostafa. 65
space mfr2 space PCMencoding space fmaxFrame space bmaxFrame / space mfr2 space PCMencoding space fmaxFrame space bmaxFrame /
"aalApp" ":" aalApp / "aalApp" ":" aalApp /
"lij" ":" sci space lsn / "lij" ":" sci space lsn /
"anycast" ":" atmGroupAddress space cdStd space "anycast" ":" atmGroupAddress space cdStd space
conScpTyp space conScpSel / conScpTyp space conScpSel /
"cache" ":" cacheEnable space cacheTimer "cache" ":" cacheEnable space cacheTimer
"chain" ":" chainPointer "chain" ":" chainPointer
eec-id = hex-U32 eec-id = hex-U32
aalType = "AAL1" / "AAL2" / "AAL3/4" / "AAL5" / "USER_DEFINED_AAL" aalType = "AAL1" / "AAL2" / "AAL3/4" / "AAL5" / "USER_DEFINED_AAL"
skipping to change at line 3845 skipping to change at line 3943
ecanEnable = on-off-or-null ecanEnable = on-off-or-null
ecanType = "G165" / "G168" / "-" ecanType = "G165" / "G168" / "-"
gcEnable = on-off-or-null gcEnable = on-off-or-null
gcLvl = generic-U16-or-null gcLvl = generic-U16-or-null
profile-row = uuiCodeRange space encoding-name space packet-length profile-row = uuiCodeRange space encoding-name space packet-length
space packet-time space space packet-time space
uuiCodeRange = decimal-uchar "-" decimal-uchar / "-" uuiCodeRange = decimal-uchar "-" decimal-uchar / "-"
encoding-name = "-" / encoding-name = "-" /
"PCMG" / "SIDG" / "SID729" / "PCMG" / "SIDG" / "SID729" /
Rajesh Kumar, Mohamed Mostafa. 63
"PCMU" / "G726-32" / "G723" / "PCMA" / "G722" / "G728" / "PCMU" / "G726-32" / "G723" / "PCMA" / "G722" / "G728" /
"G729" / "X-G729a" / "X-G729b" / "X-G729ab" / "X-G726-16" / "G729" / "X-G729a" / "X-G729b" / "X-G729ab" / "X-G726-16" /
"X-G726-24" / "X-G726-40" / "X-G7231-H" / "X-G7231-L" / "X-G726-24" / "X-G726-40" / "X-G7231-H" / "X-G7231-L" /
"X-G7231a-H" / "X-G7231a-L" / "X-G727-16" / "X-G727-24" / "X-G7231a-H" / "X-G7231a-L" / "X-G727-16" / "X-G727-24" /
"X-G727-32" / "X-G727-32" /
"X-CCD" / "X-CCD-CAS" / "GSM" / "X-GSM-HR" / "X-GSM-EFR" / "X-CCD" / "X-CCD-CAS" / "GSM" / "X-GSM-HR" / "X-GSM-EFR" /
"X-GSM-EHR" / "X-FXDMOD-3" / "1016" / "DVI4" / "L16" / "LPC" / "X-GSM-EHR" / "X-FXDMOD-3" / "1016" / "DVI4" / "L16" / "LPC" /
"MPA" / "QCELP" / "H263" / "H263-1998" / "MPA" / "QCELP" / "H263" / "H263-1998" /
"JPEG" / "H261" / "MPV" / "MP2T" / "nv" / "RED" / "X-RED" / "JPEG" / "H261" / "MPV" / "MP2T" / "nv" / "RED" / "X-RED" /
"CelB" / "L8" / "VDVI" / "MP1S" / "MP2P" "CelB" / "L8" / "VDVI" / "MP1S" / "MP2P"
skipping to change at line 3882 skipping to change at line 3978
aclr = decimal-U8-or-null aclr = decimal-U8-or-null
clpLvl = "0" / "0+1" / "-" clpLvl = "0" / "0+1" / "-"
pcr = decimal-U32-or-null pcr = decimal-U32-or-null
scr = decimal-U32-or-null scr = decimal-U32-or-null
mbs = decimal-U16-or-null mbs = decimal-U16-or-null
cdvt = decimal-U32-or-null cdvt = decimal-U32-or-null
mcr = decimal-U32-or-null mcr = decimal-U32-or-null
mfs = decimal-U16-or-null mfs = decimal-U16-or-null
fd = on-off-or-null fd = on-off-or-null
te = on-off-or-null te = on-off-or-null
Rajesh Kumar, Mohamed Mostafa. 66
nrm = generic-U8-or-null nrm = generic-U8-or-null
trm = generic-U8-or-null trm = generic-U8-or-null
cdf = generic-U8-or-null cdf = generic-U8-or-null
adtf = generic-U16-or-null adtf = generic-U16-or-null
clkrec = "NULL" / "SRTS" / "ADAPTIVE" clkrec = "NULL" / "SRTS" / "ADAPTIVE"
fecEnable = "NULL" / "LOSS_SENSITIVE" / "DELAY_SENSITIVE" fecEnable = "NULL" / "LOSS_SENSITIVE" / "DELAY_SENSITIVE"
partialFill = generic-U8 partialFill = generic-U8
bearerType = "PVC" / "SVC" / "CID" bearerType = "PVC" / "SVC" / "CID"
localInitiation = on-off-or-null localInitiation = on-off-or-null
structureEnable = on-off-or-null structureEnable = on-off-or-null
skipping to change at line 3908 skipping to change at line 4007
ted = on-off-or-null ted = on-off-or-null
fsssar = generic-U16-or-null fsssar = generic-U16-or-null
bsssar = generic-U16-or-null bsssar = generic-U16-or-null
sap = "AUDIO" / "MULTIRATE" / "-" sap = "AUDIO" / "MULTIRATE" / "-"
circuitMode = on-off-or-null circuitMode = on-off-or-null
frameMode = on-off-or-null frameMode = on-off-or-null
faxDemod = on-off-or-null faxDemod = on-off-or-null
cas = on-off-or-null cas = on-off-or-null
dtmf = on-off-or-null dtmf = on-off-or-null
mfall = on-off-or-null mfall = on-off-or-null
Rajesh Kumar, Mohamed Mostafa. 64
mfr1 = on-off-or-null mfr1 = on-off-or-null
mfr2 = on-off-or-null mfr2 = on-off-or-null
PCMencoding = "PCMA" / "PCMU" / "-" PCMencoding = "PCMA" / "PCMU" / "-"
fmaxframe = generic-U16-or-null fmaxframe = generic-U16-or-null
bmaxframe = generic-U16-or-null bmaxframe = generic-U16-or-null
aalApp = aalApp =
AAL5app = "-" / AAL5app = "-" /
"itu_h323c" / "af83" / "assuredSSCOP" / "nonassuredSSCOP" / "itu_h323c" / "af83" / "assuredSSCOP" / "nonassuredSSCOP" /
"itu_i3661"/ "itu_i3662"/ "itu_i3651" / "itu_i3661"/ "itu_i3662"/ "itu_i3651" /
"itu_i3652" / "itu_i3653" / "FRF11" / "FRF5" / "FRF8" / "itu_h2221" "itu_i3652" / "itu_i3653" / "FRF11" / "FRF5" / "FRF8" / "itu_h2221"
skipping to change at line 3945 skipping to change at line 4041
[2] IETF RFC 1889, 'RTP: A Transport Protocol for Real-Time [2] IETF RFC 1889, 'RTP: A Transport Protocol for Real-Time
Applications', Jan. 1996. Applications', Jan. 1996.
RFC1889 will be obsoleted, in a substantially backwards compatible RFC1889 will be obsoleted, in a substantially backwards compatible
manner, by the RFC that evolves out of draft-ietf-avt-rtp-new-08.txt. manner, by the RFC that evolves out of draft-ietf-avt-rtp-new-08.txt.
[3] IETF RFC 1890, 'RTP Profile for Audio and Video Conferences [3] IETF RFC 1890, 'RTP Profile for Audio and Video Conferences
with Minimal Control', Jan. 1996. with Minimal Control', Jan. 1996.
Rajesh Kumar, Mohamed Mostafa. 67
RFC1890 will be obsoleted, in a fully backwards compatible manner, RFC1890 will be obsoleted, in a fully backwards compatible manner,
by the RFC that evolves out of draft-ietf-avt-profile-new-09.txt. by the RFC that evolves out of draft-ietf-avt-profile-new-09.txt.
[4] ATMF UNI 3.1 Specification, af-uni-0010.002. Of special [4] ATMF UNI 3.1 Specification, af-uni-0010.002. Of special
interest for this document is Section 5.4.5.5, ATM Adaptation interest for this document is Section 5.4.5.5, ATM Adaptation
Layer Parameters. Layer Parameters.
[5] ATMF UNI 4.0 Signaling Specification, af-sig-0061.000. [5] ATMF UNI 4.0 Signaling Specification, af-sig-0061.000.
[6] ATMF Traffic Management Specification, Version 4.1, af-tm- [6] ATMF Traffic Management Specification, Version 4.1, af-tm-
skipping to change at line 3968 skipping to change at line 4065
Specification, version 2.0, af-vtoa-0078.000, Jan. 97. Specification, version 2.0, af-vtoa-0078.000, Jan. 97.
[8] ATMF Voice and Telephony over ATM - ATM Trunking using AAL1 for [8] ATMF Voice and Telephony over ATM - ATM Trunking using AAL1 for
Narrowband Services, version 1.0, af-vtoa-0089.000, July 1997. Narrowband Services, version 1.0, af-vtoa-0089.000, July 1997.
[9] ATMF Specifications of (DBCES) Dynamic Bandwidth Utilization - [9] ATMF Specifications of (DBCES) Dynamic Bandwidth Utilization -
in 64kbps Timeslot Trunking over ATM - using CES, af-vtoa- in 64kbps Timeslot Trunking over ATM - using CES, af-vtoa-
0085.000, July 1997. 0085.000, July 1997.
[10] ITU-T I.363.1, B-ISDN ATM Adaptation Layer Specification: Type [10] ITU-T I.363.1, B-ISDN ATM Adaptation Layer Specification: Type
Rajesh Kumar, Mohamed Mostafa. 65
1 AAL, August 1996. 1 AAL, August 1996.
[11] ITU-T I.363.2, B-ISDN ATM Adaptation Layer Specification: Type [11] ITU-T I.363.2, B-ISDN ATM Adaptation Layer Specification: Type
2 AAL, Sept. 1997. 2 AAL, Sept. 1997.
[12] ITU-T I.366.1, Segmentation and Reassembly Service Specific [12] ITU-T I.366.1, Segmentation and Reassembly Service Specific
Convergence Sublayer for AAL Type 2, June 1998. Convergence Sublayer for AAL Type 2, June 1998.
[13] ITU-T I.366.2, AAL Type 2 Reassembly Service Specific [13] ITU-T I.366.2, AAL Type 2 Reassembly Service Specific
Convergence Sublayer for Trunking, Feb. 99. Convergence Sublayer for Trunking, Feb. 99.
skipping to change at line 4008 skipping to change at line 4103
[20] rfc2474, Definition of the Differentiated Services Field (DS [20] rfc2474, Definition of the Differentiated Services Field (DS
Field) in the IPv4 and IPv6 Headers. K. Nichols, S. Blake, F. Field) in the IPv4 and IPv6 Headers. K. Nichols, S. Blake, F.
Baker, D. Black. December 1998. Baker, D. Black. December 1998.
[21] ITU-T I.363.5, B-ISDN ATM Adaptation Layer Specification: Type [21] ITU-T I.363.5, B-ISDN ATM Adaptation Layer Specification: Type
5 AAL, Aug. 1996. 5 AAL, Aug. 1996.
[22] ATMF PNNI 1.0, af-pnni-0055.000, March 1996. [22] ATMF PNNI 1.0, af-pnni-0055.000, March 1996.
Rajesh Kumar, Mohamed Mostafa. 68
[23] ietf-avt-rtp-new-05.txt, Oct. 21, 1999, RTP: A Transport [23] ietf-avt-rtp-new-05.txt, Oct. 21, 1999, RTP: A Transport
Protocol for Real-Time Applications. Protocol for Real-Time Applications.
[24] ietf-avt-profile-new-07.txt, Oct. 21, 1999, RTP Profile for [24] ietf-avt-profile-new-07.txt, Oct. 21, 1999, RTP Profile for
Audio and Video Conferences with Minimal Control. Audio and Video Conferences with Minimal Control.
[25] Media Gateway Control Protocol (MGCP), Mauricio Arango, Isaac [25] Media Gateway Control Protocol (MGCP), Mauricio Arango, Isaac
Elliott, Christian Huitema, Scott Pickett, Version 1.0, Elliott, Christian Huitema, Scott Pickett, Version 1.0,
RFC2705. RFC2705.
skipping to change at line 4031 skipping to change at line 4128
[27] IP Authentication Header, R. Atkinson, August 1995, RFC1826. [27] IP Authentication Header, R. Atkinson, August 1995, RFC1826.
[28] ITU I.371, Traffic Control and Congestion Control in the BISDN. [28] ITU I.371, Traffic Control and Congestion Control in the BISDN.
[29] ITU E.191, BISDN Numbering and Addressing. [29] ITU E.191, BISDN Numbering and Addressing.
[30] ATM Forum Addressing: Reference Guide, af-ra-0106.000. [30] ATM Forum Addressing: Reference Guide, af-ra-0106.000.
[31] http://www.isi.edu/in-notes/iana/assignments/rtp-parameters [31] http://www.isi.edu/in-notes/iana/assignments/rtp-parameters
Rajesh Kumar, Mohamed Mostafa. 66
for a list of codecs with static payload types. for a list of codecs with static payload types.
[32] ITU Q.2941-2, Digital Subscriber Signalling System No. 2 [32] ITU Q.2941-2, Digital Subscriber Signalling System No. 2
(DSS 2): Generic identifier transport extensions. (DSS 2): Generic identifier transport extensions.
[33] ITU Q.2961, Digital subscriber signalling system no.2 (DSS 2) [33] ITU Q.2961, Digital subscriber signalling system no.2 (DSS 2)
- additional traffic parameters. Also, Amendment 2 to Q.2961. - additional traffic parameters. Also, Amendment 2 to Q.2961.
[34] ITU Q. 2965.1, Digital subscriber signalling system no.2 (DSS 2) [34] ITU Q. 2965.1, Digital subscriber signalling system no.2 (DSS 2)
- Support of Quality of Service classes. - Support of Quality of Service classes.
skipping to change at line 4071 skipping to change at line 4166
[41] I.365.3, B-ISDN ATM adaptation layer sublayers: service [41] I.365.3, B-ISDN ATM adaptation layer sublayers: service
specific coordination function to provide the specific coordination function to provide the
connection-oriented transport service. connection-oriented transport service.
[42] I.365.4, B-ISDN ATM adaptation layer sublayers: Service specific [42] I.365.4, B-ISDN ATM adaptation layer sublayers: Service specific
convergence sublayer for HDLC applications. convergence sublayer for HDLC applications.
[43] Q.2110, B-ISDN ATM adaptation layer - service specific connection [43] Q.2110, B-ISDN ATM adaptation layer - service specific connection
oriented protocol (SSCOP). oriented protocol (SSCOP).
Rajesh Kumar, Mohamed Mostafa. 69
[44] af-vtoa-0113.000, ATM trunking using AAL2 for narrowband services. [44] af-vtoa-0113.000, ATM trunking using AAL2 for narrowband services.
[45] H.323-2, Packet-based multimedia communications systems. [45] H.323-2, Packet-based multimedia communications systems.
[46] af-vtoa-0083.000, Voice and Telephony Over ATM to the Desktop. [46] af-vtoa-0083.000, Voice and Telephony Over ATM to the Desktop.
[47] I.356, BISDN ATM layer cell transfer performance. [47] I.356, BISDN ATM layer cell transfer performance.
[48] ITU Q.2957, Digital Subscriber Signaling System No. 2, User to user [48] ITU Q.2957, Digital Subscriber Signaling System No. 2, User to user
signaling. signaling.
skipping to change at line 4093 skipping to change at line 4190
[50] TIA/EIA/IS-J-STD-025-A, Lawfully Authorized Electronic Surveillance, [50] TIA/EIA/IS-J-STD-025-A, Lawfully Authorized Electronic Surveillance,
May 2000. May 2000.
[51] ITU-T H.222.1, Multimedia multiplex and synchronization for audiovisual [51] ITU-T H.222.1, Multimedia multiplex and synchronization for audiovisual
communication in ATM environments. communication in ATM environments.
[52] af-vmoa-0145.000, Voice and Multimedia over ATM, Loop Emulation Service [52] af-vmoa-0145.000, Voice and Multimedia over ATM, Loop Emulation Service
using AAL2. using AAL2.
Rajesh Kumar, Mohamed Mostafa. 67
[53] FRF.5, Frame Relay/ATM PVC Network Interworking Implementation Agreement. [53] FRF.5, Frame Relay/ATM PVC Network Interworking Implementation Agreement.
[54] FRF.8, Frame Relay/ATM PVC Service Interworking Implementation Agreement. [54] FRF.8, Frame Relay/ATM PVC Service Interworking Implementation Agreement.
[55] FRF.11, Voice over Frame Relay Implementation Agreement. [55] FRF.11, Voice over Frame Relay Implementation Agreement.
[56] rfc2234, Augmented BNF for Syntax Specifications: ABNF [56] rfc2234, Augmented BNF for Syntax Specifications: ABNF
Acknowledgements Acknowledgements
The authors wish to thank several colleagues at Cisco and in the The authors wish to thank several colleagues at Cisco and in the
skipping to change at line 4121 skipping to change at line 4216
Thompson, Dan Wing and Ken Young of Cisco, Michael Brown, Rade Thompson, Dan Wing and Ken Young of Cisco, Michael Brown, Rade
Gvozdanovic, Graeme Gibbs, Tom-PT Taylor, Mark Watson Gvozdanovic, Graeme Gibbs, Tom-PT Taylor, Mark Watson
and Sophia Scoggins of Nortel Networks, Brian Rosen, Tim Dwight and Michael and Sophia Scoggins of Nortel Networks, Brian Rosen, Tim Dwight and Michael
Mackey of Marconi, Ed Guy and Petros Mouchtaris of Telcordia, Christian Mackey of Marconi, Ed Guy and Petros Mouchtaris of Telcordia, Christian
Groves of Ericsson, Charles Eckel of Vovida Networks, Tom Jepsen and Groves of Ericsson, Charles Eckel of Vovida Networks, Tom Jepsen and
Chris Gallon of Fujitsu, Mahamood Hussain of Hughes Software Systems, Chris Gallon of Fujitsu, Mahamood Hussain of Hughes Software Systems,
Sean Sheedy of nCUBE Corporation and Narendra Tulpule of Intel. The authors Sean Sheedy of nCUBE Corporation and Narendra Tulpule of Intel. The authors
also wish to thank the ISC device control group, and also wish to thank the ISC device control group, and
the MMUSIC and MEGACO subgroups of the IETF, especially Bill Foster, Jeorg the MMUSIC and MEGACO subgroups of the IETF, especially Bill Foster, Jeorg
Ott, Sean Sheedy and Brian Rosen for their help in the preparation of this Ott, Sean Sheedy and Brian Rosen for their help in the preparation of this
document. Finally, thanks are due to Naren Tulpule of Intel whose ABNF document. Finally, thanks are due to Narendra Tulpule of Intel whose ABNF
grammar was adapted for this document. grammar was adapted for this document.
Authors' Addresses Authors' Addresses
Rajesh Kumar Rajesh Kumar
Cisco Systems, Inc. Cisco Systems, Inc.
M/S SJC01/3 M/S SJC01/3
170 West Tasman Drive 170 West Tasman Drive
San Jose, CA 95134-1706 San Jose, CA 95134-1706
Phone: 1-800-250-4800 Phone: 1-800-250-4800
Email: rkumar@cisco.com Email: rkumar@cisco.com
Rajesh Kumar, Mohamed Mostafa. 70
Mohamed Mostafa Mohamed Mostafa
Cisco Systems, Inc. Cisco Systems, Inc.
M/S SJC01/3 M/S SJC01/3
170 West Tasman Drive 170 West Tasman Drive
San Jose, CA 95134-1706 San Jose, CA 95134-1706
Phone: 1-800-250-4800 Phone: 1-800-250-4800
Email: mmostafa@cisco.com Email: mmostafa@cisco.com
Full Copyright Statement Full Copyright Statement
skipping to change at line 4156 skipping to change at line 4252
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Rajesh Kumar, Mohamed Mostafa. 68
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