draft-ietf-pint-protocol-01.txt   draft-ietf-pint-protocol-02.txt 
INTERNET-DRAFT Scott Petrack, INTERNET-DRAFT Scott Petrack,
Internet Engineering Task Force Metatel Internet Engineering Task Force Metatel
PINT Working Group Lawrence Conroy, PINT Working Group Lawrence Conroy,
Issued: 3 August 1999 Siemens Roke Manor Research Issued: 14 October 1999 Siemens Roke Manor Research
Expires: 14 January 2000
The PINT Service Protocol: The PINT Service Protocol:
Extensions to SIP and SDP for IP Access to Telephone Call Services Extensions to SIP and SDP for IP Access to Telephone Call Services
<draft-ietf-pint-protocol-01.txt> <draft-ietf-pint-protocol-02.txt>
Status of this Memo Status of this Memo
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
Task Force (IETF), its areas, and its working groups. Note that Task Force (IETF), its areas, and its working groups. Note that
other groups may also distribute working documents as Internet- other groups may also distribute working documents as Internet-
Drafts. Drafts.
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Copyright Notice Copyright Notice
Copyright (c) The Internet Society (1999). All rights reserved. Copyright (c) The Internet Society (1999). All rights reserved.
Abstract Abstract
This document contains the specification of the PINT Service Protocol 1.0, This document contains the specification of the PINT Service Protocol 1.0,
which defines a protocol for invoking certain telephone services from an IP which defines a protocol for invoking certain telephone services from an IP
network. These services include placing basic calls, sending and receiving network. These services include placing basic calls, sending and receiving
faxes, and receiving content over the telephone. The protocol is specified faxes, and receiving content over the telephone. The protocol is specified
as a set of enhancements and additions to the SIP 2.0 and SDP 2.0 protocols. as a set of enhancements and additions to the SIP 2.0 and SDP protocols.
This document is intended for the PSTN-Internet Interworking (PINT) working This document is intended for the PSTN-Internet Interworking (PINT) working
group of the Internet Engineering Task Force. Comments are solicited and group of the Internet Engineering Task Force. Comments are solicited and
should be addressed to the working group's mailing list at should be addressed to the working group's mailing list at
pint@lists.research.bell-labs.com and/or the authors. pint@lists.research.bell-labs.com and/or the authors.
Petrack & Conroy [Page 1] Petrack & Conroy [Page 1]
Contents Contents
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3.4. PINT Extensions to SDP 2.0 ..................................... 10 3.4. PINT Extensions to SDP 2.0 ..................................... 10
3.4.1. Network Type "TN" and Address Type "RFC2543" ............. 11 3.4.1. Network Type "TN" and Address Type "RFC2543" ............. 11
3.4.2. Support for Data Objects within PINT ..................... 11 3.4.2. Support for Data Objects within PINT ..................... 11
3.4.2.1. Use of fmtp attributes in PINT requests ............ 13 3.4.2.1. Use of fmtp attributes in PINT requests ............ 13
3.4.2.2. Support for Remote Data Object References in PINT .. 13 3.4.2.2. Support for Remote Data Object References in PINT .. 13
3.4.2.3. Support for GSTN-based Data Objects in PINT ........ 14 3.4.2.3. Support for GSTN-based Data Objects in PINT ........ 14
3.4.2.4. Session Description support for included Data Objects 15 3.4.2.4. Session Description support for included Data Objects 15
3.4.3. Attribute Tags to pass information into the Telephone 3.4.3. Attribute Tags to pass information into the Telephone
Network .................................................. 16 Network .................................................. 16
3.4.3.1. The phone-context attribute ........................ 17 3.4.3.1. The phone-context attribute ........................ 17
3.4.3.2. Presentation Restriction attribute ................. 19 3.4.3..2. Presentation Restriction attribute ................. 19
3.4.3.3. ITU-T CalledPartyAddress attributes parameters ..... 19 3.4.3.3. ITU-T CalledPartyAddress attributes parameters ..... 19
3.4.4. The "require" attribute .................................. 20 3.4.4. The "require" attribute .................................. 20
3.5. PINT Extensions to SIP 2.0 ..................................... 21 3.5. PINT Extensions to SIP 2.0 ..................................... 21
3.5.1. Multi-part MIME (sending data along with SIP request) .... 21 3.5.1. Multi-part MIME (sending data along with SIP request) .... 21
3.5.2. Warning header ........................................... 22 3.5.2. Warning header ........................................... 22
3.5.3. Mechanism to register interest in the disposition of a PINT 3.5.3. Mechanism to register interest in the disposition of a PINT
service, and to receive indications on that disposition .. 23 service, and to receive indications on that disposition .. 23
3.5.3.1. Opening a monitoring session with a SUBSCRIBE request 23 3.5.3.1. Opening a monitoring session with a SUBSCRIBE request 23
3.5.3.2. Sending Status Indications with a NOTIFY request ... 24 3.5.3.2. Sending Status Indications with a NOTIFY request ... 24
3.5.3.3. Closing a monitoring session with a BYE request .... 25 3.5.3.3. Closing a monitoring session with an UNSUBSCRIBE
request ............................................ 25
3.5.3.4. Timing of SUBSCRIBE requests ....................... 25 3.5.3.4. Timing of SUBSCRIBE requests ....................... 25
3.5.4. The "Require:" header for PINT ........................... 26 3.5.4. The "Require:" header for PINT ........................... 26
3.5.5. PINT URLs within PINT requests ........................... 26 3.5.5. PINT URLs within PINT requests ........................... 26
3.5.5.1. PINT URLS within Request-URIs ...................... 27 3.5.5.1. PINT URLS within Request-URIs ...................... 27
3.5.6. Telephony Network Parameters within PINT URLs ............ 27 3.5.6. Telephony Network Parameters within PINT URLs ............ 27
3.5.7. REGISTER requests within PINT ............................ 28 3.5.7. REGISTER requests within PINT ............................ 28
3.5.8. BYE Requests in PINT ..................................... 28 3.5.8. BYE Requests in PINT ..................................... 28
4. Examples of PINT Requests and Responses .............................. 30 4. Examples of PINT Requests and Responses .............................. 30
4.1. A request to a call centre from an anonymous user to receive a 4.1. A request to a call centre from an anonymous user to receive a
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4.4. A request to have information read out over the phone .......... 32 4.4. A request to have information read out over the phone .......... 32
4.5. A request to send an included text page to a friend's pager .... 32 4.5. A request to send an included text page to a friend's pager .... 32
4.6. A request to send an image as a fax to phone number 4.6. A request to send an image as a fax to phone number
+972-9-956-1867 ................................................ 33 +972-9-956-1867 ................................................ 33
4.7. A request to read out over the phone two pieces of content in 4.7. A request to read out over the phone two pieces of content in
sequence ....................................................... 33 sequence ....................................................... 33
4.8. Request for the prices for ISDN to be sent to my fax machine ... 34 4.8. Request for the prices for ISDN to be sent to my fax machine ... 34
4.9. Request for a callback ......................................... 34 4.9. Request for a callback ......................................... 34
4.10.Sending a set of information in response to an enquiry ......... 34 4.10.Sending a set of information in response to an enquiry ......... 35
4.11.Sportsline "headlines" message sent to your phone/fax/pager .... 35 4.11.Sportsline "headlines" message sent to your phone/fax/pager .... 35
4.12.Automatically giving someone a fax copy of your phone bill ..... 36 4.12.Automatically giving someone a fax copy of your phone bill ..... 37
5. Security Considerations .............................................. 37 5. Security Considerations .............................................. 38
5.1. Basic Principles for PINT Use ................................. 37 5.1. Basic Principles for PINT Use ................................. 38
5.1.1. Responsibility for service requests ..................... 37 5.1.1. Responsibility for service requests ..................... 38
5.1.2. Authority to make requests .............................. 37 5.1.2. Authority to make requests .............................. 38
5.1.3. Privacy ................................................. 38 5.1.3. Privacy ................................................. 39
5.1.4. Privacy Implications of SUBSCRIBE/NOTIFY ................ 38 5.1.4. Privacy Implications of SUBSCRIBE/NOTIFY ................ 39
5.2. Registration Procedures ....................................... 39 5.2. Registration Procedures ....................................... 40
5.3. Security mechanisms and implications on PINT service .......... 39 5.3. Security mechanisms and implications on PINT service .......... 40
5.4. Summary of Security Implications .............................. 41 5.4. Summary of Security Implications .............................. 42
6. Deployment considerations and the Relationship PINT to I.N. 6. Deployment considerations and the Relationship PINT to I.N.
(Informative) ........................................................ 43 (Informative) ........................................................ 44
6.1. Web Front End to PINT Infrastructure ........................... 43 6.1. Web Front End to PINT Infrastructure ........................... 44
6.2. Redirects to Multiple Gateways ................................. 43 6.2. Redirects to Multiple Gateways ................................. 44
6.3. Competing PINT Gateways REGISTERing to offer the same service .. 44 6.3. Competing PINT Gateways REGISTERing to offer the same service .. 45
6.4. Limitations on Available Information and Request Timing for 6.4. Limitations on Available Information and Request Timing for
SUBSCRIBE ...................................................... 45 SUBSCRIBE ...................................................... 46
6.5. Parameters needed for invoking traditional PSTN Services within 6.5. Parameters needed for invoking traditional GSTN Services within
PINT ........................................................... 46 PINT ........................................................... 47
6.5.1. Service Identifier ....................................... 46 6.5.1. Service Identifier ....................................... 47
6.5.2. A and B parties .......................................... 46 6.5.2. A and B parties .......................................... 47
6.5.3. Other Service Parameters ................................. 47 6.5.3. Other Service Parameters ................................. 48
6.5.4. Service Parameter Summary ................................ 47 6.5.4. Service Parameter Summary ................................ 48
6.6. Parameter Mapping to PINT Extensions............................ 48 6.6. Parameter Mapping to PINT Extensions............................ 49
7. Open Issues and Draft State .......................................... 50 7. Open Issues and Draft State .......................................... 51
7.1. Open Issues .................................................... 50 7.1. Open Issues .................................................... 51
7.2. Draft State .................................................... 50 7.2. Draft State .................................................... 51
8. References ........................................................... 52 8. References ........................................................... 51
9. Acknowledgements ..................................................... 53 9. Acknowledgements ..................................................... 52
Appendix A: Collected ABNF for PINT Extensions .......................... 54 Appendix A: Collected ABNF for PINT Extensions .......................... 53
Appendix B: IANA Considerations ......................................... 59 Appendix B: IANA Considerations ......................................... 58
Appendix C: Authors' Addresses .......................................... 61 Appendix C: Authors' Addresses .......................................... 60
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1. Introduction 1. Introduction
The desire to invoke certain telephone call services from the Internet has The desire to invoke certain telephone call services from the Internet has
been identified by many different groups (users, public and private network been identified by many different groups (users, public and private network
operators, call center service providers, equipment vendors, see [7]). The operators, call center service providers, equipment vendors, see [7]). The
generic scenario is as follows (when the invocation is successful): generic scenario is as follows (when the invocation is successful):
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2. the server relays the request into a telephone network; 2. the server relays the request into a telephone network;
3. the telephone network performs the requested call service. 3. the telephone network performs the requested call service.
As examples, consider a user who wishes to have a call placed to his/her As examples, consider a user who wishes to have a call placed to his/her
telephone. It may be that a customer wishes to get a call from the support telephone. It may be that a customer wishes to get a call from the support
department of some business, or a user wishes to hear some remote automatic department of some business, or a user wishes to hear some remote automatic
weather service via recorded or synthesised speech. Within a local weather service via recorded or synthesised speech. Within a local
environment such a request might result in the placement of a call between environment such a request might result in the placement of a call between
employees over the internal PBX. employees over the internal PBX.
We use the term "PSTN/Internet Interworking (PINT) Service" to denote such a We use the term "PSTN/Internet Interworking (PINT) Service" to denote such
complete transaction, starting with the sending of a request from an IP a complete transaction, starting with the sending of a request from an IP
client and including the telephone call itself. PINT services are client and including the telephone call itself. PINT services are
distinguished by the fact that they always involve two separate networks: an distinguished by the fact that they always involve two separate networks:
IP network to request the placement of a call, and a telephone network to an IP network to request the placement of a call, and the Global Switched
execute the actual call. It is understood that Intelligent Network systems, Telephone Network (GSTN) to execute the actual call. It is understood that
private PBXs, cellular phone networks, and the ISDN can all be used to Intelligent Network systems, private PBXs, cellular phone networks, and
deliver PINT services. Also, the request for service might come from within the ISDN can all be used to deliver PINT services. Also, the request for
a private IP network that is disconnected from the whole Internet. service might come from within a private IP network that is disconnected
from the whole Internet.
*-*-
The requirements for the PINT protocol were deliberately restricted to The requirements for the PINT protocol were deliberately restricted to
providing the ability to invoke a small number of fixed telephone call providing the ability to invoke a small number of fixed telephone call
services. These "Milestone PINT services" are specified in section 2. Great services. These "Milestone PINT services" are specified in section 2. Great
care has been taken, however, to develop a protocol that is aligned with care has been taken, however, to develop a protocol that is aligned with
other Internet protocols where possible, so that future extensions to PINT other Internet protocols where possible, so that future extensions to PINT
could develop along with Internet conferencing. could develop along with Internet conferencing.
Within the Internet conference architecture, establishing media calls is Within the Internet conference architecture, establishing media calls is
done via a combination of protocols. SIP [1] is used to establish the done via a combination of protocols. SIP [1] is used to establish the
association between the participants within the call (this association association between the participants within the call (this association
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established is no guarantee that the media will be successfully transported. established is no guarantee that the media will be successfully transported.
(This is analogous to the fact that if a SIP invitation is accepted (This is analogous to the fact that if a SIP invitation is accepted
successfully, this is no guarantee against a subsequent failure of audio successfully, this is no guarantee against a subsequent failure of audio
hardware). hardware).
The particular requirements of PINT users lead to some new messages. When a The particular requirements of PINT users lead to some new messages. When a
PINT server agrees to send a fax to telephone B, it may be that the fax PINT server agrees to send a fax to telephone B, it may be that the fax
transmission fails after part of the fax is sent. Therefore, the PINT client transmission fails after part of the fax is sent. Therefore, the PINT client
may wish to receive information about the status of the actual telephone may wish to receive information about the status of the actual telephone
call session that was invoked as a result of the established PINT session. call session that was invoked as a result of the established PINT session.
Two new requests, SUBSCRIBE and NOTIFY, are added here to vanilla SIP to Three new requests, SUBSCRIBE, UNSIUBSCRIBE, and NOTIFY, are added here
allow this. to vanilla SIP to allow this.
The enhancements and additions specified here are not intended to alter the The enhancements and additions specified here are not intended to alter the
behaviour of baseline SIP or SDP in any way. The purpose of PINT extension behaviour of baseline SIP or SDP in any way. The purpose of PINT extension
is to extend the usual SIP/SDP services to the telephone world. Apart from is to extend the usual SIP/SDP services to the telephone world. Apart from
integrating well into existing protocols and architectures, and the integrating well into existing protocols and architectures, and the
advantages of reuse, this means that the protocol specified here can handle advantages of reuse, this means that the protocol specified here can handle
a rather wider class of call services than just the Milestone services. a rather wider class of call services than just the Milestone services.
The rest of this document is organised as follows: Section 2 describes the The rest of this document is organised as follows: Section 2 describes the
PINT Milestone services; section 3 specifies the PINT functional PINT Milestone services; section 3 specifies the PINT functional
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expressed within a PINT request. For example, it is possible to use the SDP expressed within a PINT request. For example, it is possible to use the SDP
"lang" attribute to express a language preference for the "lang" attribute to express a language preference for the
Request-to-Hear-Content Service. If a particular PINT system wishes to Request-to-Hear-Content Service. If a particular PINT system wishes to
allow requests to contain details of the telephone-network-side service, it allow requests to contain details of the telephone-network-side service, it
uses the SDP attribute mechanism (see section 3.4.2). uses the SDP attribute mechanism (see section 3.4.2).
3. PINT Functional and Protocol Architecture 3. PINT Functional and Protocol Architecture
3.1. PINT Functional Architecture 3.1. PINT Functional Architecture
Familiarity is assumed with SIP 2.0 [1] and with SDP 2.0 [2]. Familiarity is assumed with SIP 2.0 [1] and with SDP [2].
-.-.
PINT clients and servers are SIP clients and servers. SIP is used to carry PINT clients and servers are SIP clients and servers. SIP is used to carry
the request over the IP network to the correct PINT server in a secure and the request over the IP network to the correct PINT server in a secure and
reliable manner, and SDP is used to describe the telephone network session reliable manner, and SDP is used to describe the telephone network session
that is to be invoked or whose status is to be returned. that is to be invoked or whose status is to be returned.
A PINT system uses SIP proxy servers and redirect servers for their usual A PINT system uses SIP proxy servers and redirect servers for their usual
purpose, but at some point there must be a PINT server with the means to purpose, but at some point there must be a PINT server with the means to
relay received requests into a telephone system and to receive relay received requests into a telephone system and to receive
acknowledgement of these relayed requests. A PINT server with this acknowledgement of these relayed requests. A PINT server with this
capability is called a "PINT gateway". A PINT gateway appears to a SIP capability is called a "PINT gateway". A PINT gateway appears to a SIP
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both the office LAN and the office PBX. both the office LAN and the office PBX.
The Executive System that lies beyond the PINT gateway is outside the scope The Executive System that lies beyond the PINT gateway is outside the scope
of PINT. of PINT.
3.2. PINT Protocol Architecture 3.2. PINT Protocol Architecture
This section explains how SIP and SDP work in combination to convey the This section explains how SIP and SDP work in combination to convey the
information necessary to invoke telephone network sessions. information necessary to invoke telephone network sessions.
*-*- -.-.
The following list summarises the extension features used in PINT 1.0. The following list summarises the extension features used in PINT 1.0.
Following on from this the features are considered separately for SDP and Following on from this the features are considered separately for SDP and
then for SIP: then for SIP:
1) Telephony URLs in SDP Contact Fields 1) Telephony URLs in SDP Contact Fields
2) Refinement of SIP/SDP Telephony URLs 2) Refinement of SIP/SDP Telephony URLs
* Inclusion of private dialling plans * Inclusion of private dialling plans
3) Specification of Telephone Service Provider (TSP) and/or 3) Specification of Telephone Service Provider (TSP) and/or
phone-context URL-parameters phone-context URL-parameters
4) Data Objects as session media 4) Data Objects as session media
4a) Protocol Transport formats to indicate the treatment of the media 4a) Protocol Transport formats to indicate the treatment of the media
within the PSTN within the GSTN
5) Implicit (Indirect) media streams and opaque arguments 5) Implicit (Indirect) media streams and opaque arguments
6) In-line data objects using multipart/mime 6) In-line data objects using multipart/mime
7) Refinement/Clarification of Opaque arguments passed onwards to Executive 7) Refinement/Clarification of Opaque arguments passed onwards to Executive
Systems Systems
* Framework for Presentation Restriction Indication * Framework for Presentation Restriction Indication
* Framework for Q.763 arguments * Framework for Q.763 arguments
8) An extension mechanism for SDP to specify strictures and force 8) An extension mechanism for SDP to specify strictures and force
failure when a recipient does NOT support the specified extensions, failure when a recipient does NOT support the specified extensions,
using "require" headers. using "require" headers.
9) Mandatory support for "Warning" headers to give more detailed 9) Mandatory support for "Warning" headers to give more detailed
information on request disposition. information on request disposition.
10) Mechanism to register interest in the disposition of a requested 10) Mechanism to register interest in the disposition of a requested
service, and to receive indications on that disposition. service, and to receive indications on that disposition.
-*-*
Both PINT and SIP rely on features of MIME[4]. The use of SIP 2.0 is implied Both PINT and SIP rely on features of MIME[4]. The use of SIP 2.0 is implied
by PINT 1.0, and this also implies compliance with version 1.0 of MIME. by PINT 1.0, and this also implies compliance with version 1.0 of MIME.
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*-*-
3.2.1. SDP operation in PINT 3.2.1. SDP operation in PINT
The SDP payload contains a description of the particular telephone network The SDP payload contains a description of the particular telephone network
session that the requestor wishes to occur in the PSTN. This information session that the requestor wishes to occur in the GSTN. This information
includes such things as the telephone network address (i.e. the "telephone includes such things as the telephone network address (i.e. the "telephone
number") of the terminal(s) involved in the call, an indication of the media number") of the terminal(s) involved in the call, an indication of the media
type to be transported (e.g. audio, text, image or application data), and an type to be transported (e.g. audio, text, image or application data), and an
indication if the information is to be transported over the telephone indication if the information is to be transported over the telephone
network via voice, fax, or pager transport. An indication of the content to network via voice, fax, or pager transport. An indication of the content to
be sent to the remote telephone terminal (if there is any) is also included. be sent to the remote telephone terminal (if there is any) is also included.
SDP is flexible enough to convey these parameters independently. For SDP is flexible enough to convey these parameters independently. For
example, a request to send some text via voice transport will be fulfilled example, a request to send some text via voice transport will be fulfilled
by invoking some text-to-speech-over-the-phone service, and a request to by invoking some text-to-speech-over-the-phone service, and a request to
send text via fax will be fulfilled by invoking some text-to-fax service. send text via fax will be fulfilled by invoking some text-to-fax service.
The following is a list of PINT 1.0 enhancements and additions to SDP. The following is a list of PINT 1.0 enhancements and additions to SDP.
-.-.
a. A new network type "TN" and address types "RFC2543" and "X-..." a. A new network type "TN" and address types "RFC2543" and "X-..."
(section 3.4.1) (section 3.4.1)
b. New media types "text", "image", and "application", b. New media types "text", "image", and "application",
new protocol transport keywords "voice", "fax" and new protocol transport keywords "voice", "fax" and
"pager" and the associated format types and attribute tags "pager" and the associated format types and attribute tags
(section 3.4.2) (section 3.4.2)
c. New format specific attributes for included content data c. New format specific attributes for included content data
(section 3.4.2.4) (section 3.4.2.4)
d. New attribute tags, used to pass information to the telephone d. New attribute tags, used to pass information to the telephone
network (section 3.4.3) network (section 3.4.3)
e. A new attribute tag "require", used by a client to indicate that e. A new attribute tag "require", used by a client to indicate that
some attribute is required to be supported in the server some attribute is required to be supported in the server
(section 3.4.4) (section 3.4.4)
*-*-
3.2.2. SIP Operation in PINT 3.2.2. SIP Operation in PINT
SIP is used to carry the request for telephone service from the PINT client SIP is used to carry the request for telephone service from the PINT client
to the PINT gateway, and may include a telephone number if needed for the to the PINT gateway, and may include a telephone number if needed for the
particular service. The following is a complete list of PINT enhancements particular service. The following is a complete list of PINT enhancements
and additions to SIP: and additions to SIP:
f. The multipart MIME payloads (section 3.5.1) f. The multipart MIME payloads (section 3.5.1)
g. Mandatory support for "Warning:" headers (section 3.5.2) g. Mandatory support for "Warning:" headers (section 3.5.2)
h. The SUBSCRIBE and NOTIFY requests (section 3.5.3) h. The SUBSCRIBE and NOTIFY, and UNSUBSCRIBE requests (section 3.5.3)
i. Require: headers (section 3.5.4) i. Require: headers (section 3.5.4)
j. A format for PINT URLS within a PINT request (section 3.5.5) j. A format for PINT URLS within a PINT request (section 3.5.5)
k. Telephone Network Parameters within PINT URLs (section 3.5.6) k. Telephone Network Parameters within PINT URLs (section 3.5.6)
*-*-
Section 3.5.8 contains remarks about how BYE requests are used within PINT. Section 3.5.8 contains remarks about how BYE requests are used within PINT.
This is not an extension to baseline SIP; it is included here only for This is not an extension to baseline SIP; it is included here only for
clarification of the semantics when used with telephone network sessions. clarification of the semantics when used with telephone network sessions.
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3.3. REQUIRED and OPTIONAL elements for PINT compliance 3.3. REQUIRED and OPTIONAL elements for PINT compliance
*-*-
Of these, only the TN network type (with its associated RFC2543 address Of these, only the TN network type (with its associated RFC2543 address
type) and the "require" attribute MUST be supported by PINT 1.0 clients type) and the "require" attribute MUST be supported by PINT 1.0 clients
and servers. In practice, most PINT service requests will use other changes, and servers. In practice, most PINT service requests will use other changes,
of which references to Data Objects in requests are most likely to appear of which references to Data Objects in requests are most likely to appear
in PINT requests. in PINT requests.
Each of the other new PINT constructs enables a different function, and a Each of the other new PINT constructs enables a different function, and a
client or server that wishes to enable that particular function MUST do so client or server that wishes to enable that particular function MUST do so
by the construct specified in this document. For example, building a PINT by the construct specified in this document. For example, building a PINT
client and server that provide only the Request-to-Call telephone call client and server that provide only the Request-to-Call telephone call
service, without support for the other Milestone services, is allowed. service, without support for the other Milestone services, is allowed.
-.-.
The "Require:" SIP header and the "require" attribute provide a mechanism The "Require:" SIP header and the "require" attribute provide a mechanism
that can be used by clients and servers to signal their need and/or that can be used by clients and servers to signal their need and/or
ability to support specific "new" PINT protocol elements. ability to support specific "new" PINT protocol elements.
It should be noted that many optional features of SIP and SDP make sense as It should be noted that many optional features of SIP and SDP make sense as
specified in the PINT context. One example is the SDP a=lang: attribute, specified in the PINT context. One example is the SDP a=lang: attribute,
which can be used to describe the preferred language of the callee. Another which can be used to describe the preferred language of the callee. Another
example is the use of the "t=" parameter to indicate that the time at which example is the use of the "t=" parameter to indicate that the time at which
the PINT service is to be invoked. This is the normal use of the "t=" field. the PINT service is to be invoked. This is the normal use of the "t=" field.
A third example is the quality attributes. Any SIP or SDP option or A third example is the quality attributes. Any SIP or SDP option or
facility is available to PINT clients and servers without change. facility is available to PINT clients and servers without change.
*-*-
Conversely, support for Data Objects within Internet Conference sessions may Conversely, support for Data Objects within Internet Conference sessions may
be useful, even if the aim is not to provide a PSTN service request. In this be useful, even if the aim is not to provide a GSTN service request. In this
case, the extensions covering these items may be incorporated into an case, the extensions covering these items may be incorporated into an
otherwise "plain" SIP/SDP invitation. Likewise, support for SDP "require" otherwise "plain" SIP/SDP invitation. Likewise, support for SDP "require"
may be useful, as a framework for addition of features to a "traditional" may be useful, as a framework for addition of features to a "traditional"
SIP/SDP infrastructure. Again, these may be convenient to incorporate into SIP/SDP infrastructure. Again, these may be convenient to incorporate into
SIP/SDP implementations that would not be used for PINT service requests. SIP/SDP implementations that would not be used for PINT service requests.
Such additions are beyond the scope of this document, however. Such additions are beyond the scope of this document, however.
3.4. PINT Extensions to SDP 2.0 3.4. PINT Extensions to SDP
PINT 1.0 adds to SDP the possibility to describe audio, fax, and pager PINT 1.0 adds to SDP the possibility to describe audio, fax, and pager
telephone sessions. It is deliberately designed to hide the underlying telephone sessions. It is deliberately designed to hide the underlying
technical details and complexity of the telephone network. The only network technical details and complexity of the telephone network. The only network
type defined for PINT is the generic "TN" (Telephone Network). More precise type defined for PINT is the generic "TN" (Telephone Network). More precise
tags such as "ISDN", "GSM", are not defined. Similarly, the transport tags such as "ISDN", "GSM", are not defined. Similarly, the transport
protocols are designated simply as "fax", "voice", and "pager"; there are no protocols are designated simply as "fax", "voice", and "pager"; there are no
more specific identifiers for the various telephone network voice, fax, or more specific identifiers for the various telephone network voice, fax, or
pager protocols. Similarly, the data to be transported is identified only as pager protocols. Similarly, the data to be transported is identified only as
a MIME type, such as "text" data, "image" data, or some more general a MIME type, such as "text" data, "image" data, or some more general
skipping to change at page 11, line 14 skipping to change at page 11, line 14
This section gives details of the new SDP keywords. This section gives details of the new SDP keywords.
3.4.1. Network Type "TN" and Address Type "RFC2543" 3.4.1. Network Type "TN" and Address Type "RFC2543"
The TN ("Telephone Network") network type is used to indicate that the The TN ("Telephone Network") network type is used to indicate that the
terminal is connected to a telephone network. terminal is connected to a telephone network.
The address types allowed for network type TN are "RFC2543" and private The address types allowed for network type TN are "RFC2543" and private
address types, which MUST begin with an "X-". address types, which MUST begin with an "X-".
-.-.
Address type RFC2543 is followed by a string conforming to a subset of the Address type RFC2543 is followed by a string conforming to a subset of the
"telephone-subscriber" BNF specified in RFC2543, (this is specified in "telephone-subscriber" BNF specified in RFC2543, (this is specified in
figure 4 of SIP [1]). Note that this BNF is NOT identical to the BNF that figure 4 of SIP [1]). Note that this BNF is NOT identical to the BNF that
defines the "phone-number" within the "p=" field of SDP. defines the "phone-number" within the "p=" field of SDP.
Examples: Examples:
c= TN RFC2543 +1-201-406-4090 c= TN RFC2543 +1-201-406-4090
c= TN RFC2543 12014064090 c= TN RFC2543 12014064090
*-*-
A telephone-subscriber string is of one of two types: global-phone-number or A telephone-subscriber string is of one of two types: global-phone-number or
local-phone-number. These are distinguished by preceeding a local-phone-number. These are distinguished by preceeding a
global-phone-number with a "plus" sign ("+"). A global-phone-number is by global-phone-number with a "plus" sign ("+"). A global-phone-number is by
default to be interpreted as an internationally significant E.164 Number default to be interpreted as an internationally significant E.164 Number
Plan Address, as defined by [6], whilst a local-phone-number is a number Plan Address, as defined by [6], whilst a local-phone-number is a number
specified in the default dialling plan within the context of the recipient specified in the default dialling plan within the context of the recipient
PINT Gateway. PINT Gateway.
An implementation MAY use private addressing types, which can be useful An implementation MAY use private addressing types, which can be useful
within a local domain. These address types MUST begin with an "X-", and within a local domain. These address types MUST begin with an "X-", and
skipping to change at page 11, line 49 skipping to change at page 11, line 48
c= TN X-mytype.mydomain.com A*8-HELEN c= TN X-mytype.mydomain.com A*8-HELEN
where "X-mytype.mydomain.com" identifies this private address type, and where "X-mytype.mydomain.com" identifies this private address type, and
"A*8-HELEN" is the number in this format. Such a format is defined as an "A*8-HELEN" is the number in this format. Such a format is defined as an
"OtherAddr" in the ABNF of Appendix A. "OtherAddr" in the ABNF of Appendix A.
Note that most dialable telephone numbers are expressable as Note that most dialable telephone numbers are expressable as
local-phone-numbers within address RFC2543; new address types should only be local-phone-numbers within address RFC2543; new address types should only be
used for formats which cannot be so written. used for formats which cannot be so written.
*-*-
3.4.2. Support for Data Objects within PINT 3.4.2. Support for Data Objects within PINT
One significant change over traditional SIP/SDP Internet Conference sessions One significant change over traditional SIP/SDP Internet Conference sessions
with PINT is that a PINT service request may refer to a Data Object to be with PINT is that a PINT service request may refer to a Data Object to be
used as source information in that request. For example, a PINT service used as source information in that request. For example, a PINT service
request may specify a document to be processed as part of a GSTN service by request may specify a document to be processed as part of a GSTN service by
which a Fax is sent. Similarly, a GSTN service may be take a Web page and which a Fax is sent. Similarly, a GSTN service may be take a Web page and
result in a vocoder processing that page and speaking the contents over a result in a vocoder processing that page and speaking the contents over a
telephone. telephone.
skipping to change at page 12, line 28 skipping to change at page 12, line 28
media-field = "m=" media space port ["/" integer] media-field = "m=" media space port ["/" integer]
space proto 1*(space fmt) CRLF space proto 1*(space fmt) CRLF
When used within PINT requests, the definition of the sub-fields is When used within PINT requests, the definition of the sub-fields is
expanded slightly. expanded slightly.
The Media sub-field definition is relaxed to accept all of the discrete The Media sub-field definition is relaxed to accept all of the discrete
"top-level" media types defined in [4]. In the milestone services the "top-level" media types defined in [4]. In the milestone services the
discrete type "video" is not used, and the extra types "data" and "control" discrete type "video" is not used, and the extra types "data" and "control"
are likewise not needed. The use of these types is not precluded, but the are likewise not needed. The use of these types is not precluded, but the
behaviour expected of a PINT Gateway receiving a request including such a behaviour expected of a PINT Gateway receiving a request including such a
type is not defined here. type is not defined here.
-.-.
The Port sub-field has no meaning in PINT requests as the destination The Port sub-field has no meaning in PINT requests as the destination
terminals are specified using "TN" addressing, so the value of the port terminals are specified using "TN" addressing, so the value of the port
sub-field in PINT requests is normally set to "1". A value of "0" may sub-field in PINT requests is normally set to "1". A value of "0" may
be used as in SDP to indicate that the terminal is not receiving media. be used as in SDP to indicate that the terminal is not receiving media.
This is useful to indicate that a telephone terminal has gone "on hold" This is useful to indicate that a telephone terminal has gone "on hold"
temporarily. Likewise, the optional integer sub-field is not used in PINT. temporarily. Likewise, the optional integer sub-field is not used in PINT.
As mentioned in [2], the Transport Protocol sub-field is specific to the As mentioned in [2], the Transport Protocol sub-field is specific to the
associated Address Type. In the case that the Address Type in the preceeding associated Address Type. In the case that the Address Type in the preceeding
Contact field is one of those defined for use with the Network Type "TN", Contact field is one of those defined for use with the Network Type "TN",
skipping to change at page 12, line 53 skipping to change at page 12, line 53
or disposition of the resulting GSTN service. Thus, for transport protocol or disposition of the resulting GSTN service. Thus, for transport protocol
"voice", the intent is that the service will result in a GSTN voice call, "voice", the intent is that the service will result in a GSTN voice call,
whilst for protocol "fax" the result will be a GSTN fax transmission, and whilst for protocol "fax" the result will be a GSTN fax transmission, and
protocol "pager" will result in a pager message being sent. protocol "pager" will result in a pager message being sent.
Note that this sub-field does not necessarily dictate the media type and Note that this sub-field does not necessarily dictate the media type and
subtype of any source data; for example, one of the milestone services calls subtype of any source data; for example, one of the milestone services calls
for a textual source to be vocoded and spoken in a resulting telephone for a textual source to be vocoded and spoken in a resulting telephone
service call. The transport protocol value in this case would be "voice", service call. The transport protocol value in this case would be "voice",
whilst the media type would be "text". whilst the media type would be "text".
-.-.
The Fmt sub-field is described in [2] as being transport protocol-specific. The Fmt sub-field is described in [2] as being transport protocol-specific.
When used within PINT requests having one of the above protocol values, When used within PINT requests having one of the above protocol values,
this sub-field consists of a list of one or more values, each of which is this sub-field consists of a list of one or more values, each of which is
a defined MIME sub-type of the associated Media sub-field value. The a defined MIME sub-type of the associated Media sub-field value. The
special value "-" is allowed, meaning that there is no MIME sub-type. special value "-" is allowed, meaning that there is no MIME sub-type.
This sub-field retains (from [2]) its meaning that the list will contain This sub-field retains (from [2]) its meaning that the list will contain
a set of alternative sub-types, with the first being the preferred value. a set of alternative sub-types, with the first being the preferred value.
-.-.
For experimental purposes and by mutual consent of the sender and recipient, For experimental purposes and by mutual consent of the sender and recipient,
a sub-type value may be specified as an <X-token>, i.e. a character string a sub-type value may be specified as an <X-token>, i.e. a character string
starting with "X-". The use of such values is discouraged, and if such a starting with "X-". The use of such values is discouraged, and if such a
value is expected to find common use then it SHOULD be registered with IANA value is expected to find common use then it SHOULD be registered with IANA
using the standard content type registration process (see Appendix C). using the standard content type registration process (see Appendix C).
-.-.
When the Fmt parameter is the single character "-" ( a dash ), this is When the Fmt parameter is the single character "-" ( a dash ), this is
interpreted as meaning that a unspecified or default sub-type should be used interpreted as meaning that a unspecified or default sub-type should be used
for this service. Thus, the media field value "m=audio 1 voice -<CRLF>" is for this service. Thus, the media field value "m=audio 1 voice -<CRLF>" is
taken to mean that a voice call is requested, using whatever audio sub type taken to mean that a voice call is requested, using whatever audio sub type
is deemed appropriate by the Executive System. PINT service is a special is deemed appropriate by the Executive System. PINT service is a special
case, in that the request comes from the IP network but the service call is case, in that the request comes from the IP network but the service call is
provided within the GSTN. Thus the service request will not normally be able provided within the GSTN. Thus the service request will not normally be able
to define the particular codec used for the resulting GSTN service call. If to define the particular codec used for the resulting GSTN service call. If
such an intent IS required, then the quality attribute may be used (see such an intent IS required, then the quality attribute may be used (see
"Suggested Attributes" section of [2]). "Suggested Attributes" section of [2]).
skipping to change at page 15, line 16 skipping to change at page 15, line 16
could, for example, be needed to authorise access to a document held on the could, for example, be needed to authorise access to a document held on the
GSTN rather than being required merely to disambiguate the data object. The GSTN rather than being required merely to disambiguate the data object. The
purpose to which an opaque reference is put, however, is out of scope for purpose to which an opaque reference is put, however, is out of scope for
this document. It is merely an indicator carried within a PINT Request. this document. It is merely an indicator carried within a PINT Request.
An opaque reference may have no value in the case where the value to be used An opaque reference may have no value in the case where the value to be used
is implicit in the rest of the request. For example, suppose some company is implicit in the rest of the request. For example, suppose some company
wishes to use PINT to implement a "fax-back service". In their current wishes to use PINT to implement a "fax-back service". In their current
implementation, the image(s) to be faxed are entirely defined by the implementation, the image(s) to be faxed are entirely defined by the
telephone number dialled. Within the PINT request, this telephone number telephone number dialled. Within the PINT request, this telephone number
would appear within the "to:" field of the PINT request, and so there would appear within the "To:" field of the PINT request, and so there
is no need for an opaque reference value. is no need for an opaque reference value.
If there are several resolutions for a PINT Service Request, and one of If there are several resolutions for a PINT Service Request, and one of
these is an opaque reference with no value, then that opaque reference MUST these is an opaque reference with no value, then that opaque reference MUST
be included in the attribute line, but with an empty value field. be included in the attribute line, but with an empty value field.
For example: For example:
c= TN RFC2543 +1-201-406-4090 c= TN RFC2543 +1-201-406-4090
m= text 1 fax plain m= text 1 fax plain
a=fmtp:plain spr:<Content-ID> opr: a=fmtp:plain spr:<Content-ID> opr:
skipping to change at page 15, line 44 skipping to change at page 15, line 44
further resolution. further resolution.
For example: For example:
c= TN RFC2543 +1-201-406-4090 c= TN RFC2543 +1-201-406-4090
m= text 1 fax - m= text 1 fax -
means that there is an implied content stored on the GSTN, and that this is means that there is an implied content stored on the GSTN, and that this is
uniquely identified by the combination of SIP To-URI and the Contact field uniquely identified by the combination of SIP To-URI and the Contact field
of the session description. of the session description.
*-*-
3.4.2.4. Session Description support for included Data Objects 3.4.2.4. Session Description support for included Data Objects
As an alternative to pointing to the data via a URI or an opaque reference As an alternative to pointing to the data via a URI or an opaque reference
to a data item held on the GSTN, it is possible to include the content data to a data item held on the GSTN, it is possible to include the content data
within the SIP request itself. This is done by using multipart MIME for the within the SIP request itself. This is done by using multipart MIME for the
SIP payload. The first MIME part contains the SDP description of the SIP payload. The first MIME part contains the SDP description of the
telephone network session to be executed. The other MIME parts contain the telephone network session to be executed. The other MIME parts contain the
content data to be transported. content data to be transported.
Format specific attribute lines within the session description are used to Format specific attribute lines within the session description are used to
skipping to change at page 16, line 11 skipping to change at page 16, line 11
indicates the Content-ID of the MIME part of the request that contains the indicates the Content-ID of the MIME part of the request that contains the
actual data, and is defined as: actual data, and is defined as:
<sub-part-ref> := ("spr:" Content-ID) <sub-part-ref> := ("spr:" Content-ID)
where Content-ID is as defined in Appendix A of [3] and in [10]). where Content-ID is as defined in Appendix A of [3] and in [10]).
For example: For example:
c= TN RFC2543 +1-201-406-4090 c= TN RFC2543 +1-201-406-4090
m= text 1 fax plain m= text 1 fax plain
a=fmtp:plain spr:<Content-ID> a=fmtp:plain spr:<Content-ID>
*-*-
The <Content-ID> parameter is the Content-ID of one of the MIME parts inside The <Content-ID> parameter is the Content-ID of one of the MIME parts inside
the message, and this fragment means that the requesting user would like the the message, and this fragment means that the requesting user would like the
data object held in the sub-part of this message labelled <Content-ID> to be data object held in the sub-part of this message labelled <Content-ID> to be
faxed to the machine at phone number +1-201-406-4090. faxed to the machine at phone number +1-201-406-4090.
*-*-
See also section 3.5.1 for a discussion on the support needed in the See also section 3.5.1 for a discussion on the support needed in the
enclosing SIP request for included data objects. enclosing SIP request for included data objects.
3.4.3. Attribute Tags to pass information into the Telephone Network 3.4.3. Attribute Tags to pass information into the Telephone Network
*-*-
It may be desired to include within the PINT request service parameters It may be desired to include within the PINT request service parameters
that can be understood only by some entity in the "Telephone Network that can be understood only by some entity in the "Telephone Network
Cloud". SDP attribute parameters are used for this purpose. They MAY appear Cloud". SDP attribute parameters are used for this purpose. They MAY appear
within a particular media description or outside of a media description. within a particular media description or outside of a media description.
These attributes may also appear as parameters within PINT URLS (see section These attributes may also appear as parameters within PINT URLS (see section
3.5.6) as part of a SIP request. 3.5.6) as part of a SIP request.
This is necessary so that telephone terminals that require the attributes to This is necessary so that telephone terminals that require the attributes to
be defined can appear within the To: line of a PINT request as well as be defined can appear within the To: line of a PINT request as well as
skipping to change at page 16, line 54 skipping to change at page 16, line 52
number of networks (such as an '800' freephone number). number of networks (such as an '800' freephone number).
c. The telephone number might be reachable only within a c. The telephone number might be reachable only within a
single telephone network (such as the '152' customer service single telephone network (such as the '152' customer service
number of BT). Similarly, the number might be an internal number of BT). Similarly, the number might be an internal
corporate extension reachable only within the PBX. corporate extension reachable only within the PBX.
However, as noted above, it is not usually necessary to use SDP However, as noted above, it is not usually necessary to use SDP
attributes to specify the phone context. URLs such as 152@pint.bt.co.il attributes to specify the phone context. URLs such as 152@pint.bt.co.il
within the To: and From: headers and/or Request-URI, normally offer within the To: and From: headers and/or Request-URI, normally offer
sufficient context to resolve telephone numbers. sufficient context to resolve telephone numbers.
-.-.
If the client wishes the request to fail if the attributes are not If the client wishes the request to fail if the attributes are not
supported, these attributes should be used in conjunction with the supported, these attributes should be used in conjunction with the
"require" attribute (section 3.4.4) and the "Require:org.ietf.sdp.require" "require" attribute (section 3.4.4) and the "Require:org.ietf.sdp.require"
header (section 3.5.4). header (section 3.5.4).
It is not possible to standardise every possible internal telephone network It is not possible to standardise every possible internal telephone network
parameter. PINT 1.0 attributes have been chosen for specification because parameter. PINT 1.0 attributes have been chosen for specification because
they are common enough that many different PINT systems will want to use they are common enough that many different PINT systems will want to use
them, and therefore interoperability will be increased by having a single them, and therefore interoperability will be increased by having a single
specification. specification.
*-*-
Proprietary attribute "a=" lines, that by definition are not interoperable, Proprietary attribute "a=" lines, that by definition are not interoperable,
may be nonetheless useful when it is necessary to transport some proprietary may be nonetheless useful when it is necessary to transport some proprietary
internal telephone network variables over the IP network, for example to internal telephone network variables over the IP network, for example to
identify the order in which service call legs should be made. These private identify the order in which service call legs should be made. These private
attributes SHOULD BE, however, subject to the same IANA registration attributes SHOULD BE, however, subject to the same IANA registration
procedures mentioned in the SDP specification[2] (see also this Appendix C). procedures mentioned in the SDP specification[2] (see also this Appendix C).
3.4.3.1. The phone-context attribute 3.4.3.1. The phone-context attribute
An attribute is specified to enable "remote local dialling". This is the An attribute is specified to enable "remote local dialling". This is the
skipping to change at page 18, line 25 skipping to change at page 18, line 25
c= TN RFC2543 1-800-765-4321 c= TN RFC2543 1-800-765-4321
a=phone-context:+1 a=phone-context:+1
This describes an terminal whose address in North America (E.164 country This describes an terminal whose address in North America (E.164 country
code 1) is 1-800-765-4321. code 1) is 1-800-765-4321.
The two telephone terminals described by examples 1 and 2 are different; in The two telephone terminals described by examples 1 and 2 are different; in
fact they are located in different countries. fact they are located in different countries.
Example 3: Example 3:
-.-.
c=TN RFC2543 123 c=TN RFC2543 123
a=phone-context:+97252 a=phone-context:+97252
-.-.
This describes a terminal whose address when dialled from within the network This describes a terminal whose address when dialled from within the network
identified by +97252 is the string "123". It so happens that +97252 defines identified by +97252 is the string "123". It so happens that +97252 defines
one of the Israeli cell phone providers, and 123 reaches customer service one of the Israeli cell phone providers, and 123 reaches customer service
when dialled within that network. when dialled within that network.
-.-.
It may well be useful or necessary to use the SDP "require" parameter in It may well be useful or necessary to use the SDP "require" parameter in
conjunction with the phone-context attribute. conjunction with the phone-context attribute.
Example 4: Example 4:
c= TN RFC2543 321 c= TN RFC2543 321
a=phone-context:X-acme.com 23 a=phone-context:X-acme.com-23
This might describe the telephone terminal that is at extension 321 of PBX This might describe the telephone terminal that is at extension 321 of PBX
number 23 within the acme.com private PBX network. It is expected that such number 23 within the acme.com private PBX network. It is expected that such
a description would be understandable by the acme.com PINT server that a description would be understandable by the acme.com PINT server that
receives the request. receives the request.
Note that if the PINT server receiving the request is inside the acme.com Note that if the PINT server receiving the request is inside the acme.com
network, the same terminal might be addressable as follows: network, the same terminal might be addressable as follows:
c= TN RFC2543 7-23-321 c= TN RFC2543 7-23-321
(assuming that "7" is dialled in order to reach the private PBX network from (assuming that "7" is dialled in order to reach the private PBX network from
within acme.com) within acme.com)
*-*-
*-*-
3.4.3.2. Presentation Restriction attribute 3.4.3.2. Presentation Restriction attribute
Although it has no affect on the transport of the service request through Although it has no affect on the transport of the service request through
the IP Network, there may be a requirement to allow originators of a PINT the IP Network, there may be a requirement to allow originators of a PINT
service request to indicate whether or not they wish the "B party" in service request to indicate whether or not they wish the "B party" in
the resulting service call to be presented with the "A party's" calling the resulting service call to be presented with the "A party's" calling
telephone number. It is a legal requirement in some jurisdictions that a telephone number. It is a legal requirement in some jurisdictions that a
caller be able to select whether or not their correspondent can find out caller be able to select whether or not their correspondent can find out
the calling telephone number (using Automatic Number Indication or Caller the calling telephone number (using Automatic Number Indication or Caller
Display or Calling Line Identity Presentation equipment). Thus an attribute Display or Calling Line Identity Presentation equipment). Thus an attribute
skipping to change at page 19, line 40 skipping to change at page 19, line 39
address is, by default, set to NOT present its identity to correspondents, address is, by default, set to NOT present its identity to correspondents,
and the originator wants to do so for this particular call. It is in keeping and the originator wants to do so for this particular call. It is in keeping
with the aim of this attribute to allow the originator to specify what with the aim of this attribute to allow the originator to specify what
treatment they want for the requested service call. treatment they want for the requested service call.
The expected interpretation of this attribute is that, if it is present and The expected interpretation of this attribute is that, if it is present and
the value is "false" then the Calling Line Identity CAN be presented to the the value is "false" then the Calling Line Identity CAN be presented to the
correspondent terminal, whilst if it is "true" then it if possible the correspondent terminal, whilst if it is "true" then it if possible the
Executive System is requested to NOT present the Calling Line Identity. Executive System is requested to NOT present the Calling Line Identity.
*-*-
3.4.3.3. ITU-T CalledPartyAddress attributes parameters 3.4.3.3. ITU-T CalledPartyAddress attributes parameters
These attributes correspond to fields that appear within the ITU-T Q.763 These attributes correspond to fields that appear within the ITU-T Q.763
"CalledPartyAddress" field (see [8] ,section 3.9). PINT clients "CalledPartyAddress" field (see [8] ,section 3.9). PINT clients
use these attributes in order to specify further parameters relating to use these attributes in order to specify further parameters relating to
Terminal Addresses, in the case when the address indicates a Terminal Addresses, in the case when the address indicates a
"local-phone-number". In the case that the PINT request contains a "local-phone-number". In the case that the PINT request contains a
reference to a PSTN terminal, the parameters may be required to correctly reference to a GSTN terminal, the parameters may be required to correctly
identify that remote terminal. identify that remote terminal.
*-*-
The general form of this attribute is "a=Q763-<token>((":" <value>) |"")". The general form of this attribute is "a=Q763-<token>((":" <value>) |"")".
Three of the possible elements and their use in SDP attributes are described Three of the possible elements and their use in SDP attributes are described
here. Where other Q763 elements are to be used, then these should be the here. Where other Q763 elements are to be used, then these should be the
subject of further specification to define the syntax of the attribute subject of further specification to define the syntax of the attribute
mapping. It is recommended that any such specification maintains the value mapping. It is recommended that any such specification maintains the value
sets shown in Q.763. sets shown in Q.763.
The defined attributes are: The defined attributes are:
a=Q763-nature: - indicates the "nature of address indicator". a=Q763-nature: - indicates the "nature of address indicator".
skipping to change at page 20, line 46 skipping to change at page 20, line 46
"1" routing to internal network number not "1" routing to internal network number not
allowed allowed
The values have been chosen to coincide with the values in Q.763. The values have been chosen to coincide with the values in Q.763.
Note that it is possible to use a local-phone-number and indicate via Note that it is possible to use a local-phone-number and indicate via
attributes that the number is in fact an internationally significant attributes that the number is in fact an internationally significant
E.164 number. Normally this SHOULD NOT be done; an internationally E.164 number. Normally this SHOULD NOT be done; an internationally
significant E.164 number is indicated by using a "global-phone-number" significant E.164 number is indicated by using a "global-phone-number"
for the address string. for the address string.
-.-.
3.4.4. The "require" attribute 3.4.4. The "require" attribute
-.-.
According to the SDP specification, a PINT server is allowed simply to According to the SDP specification, a PINT server is allowed simply to
ignore attribute parameters that it does not understand. In order to force a ignore attribute parameters that it does not understand. In order to force a
server to fail a request if it does not understand one of the PINT server to fail a request if it does not understand one of the PINT
attributes, a client should use the "require" attribute, specified as attributes, a client should use the "require" attribute, specified as
follows: follows:
-.-.
a=require:<attribute-list> a=require:<attribute-list>
where the attribute-list is a comma-separated list of attributes that appear where the attribute-list is a comma-separated list of attributes that appear
elsewhere in the session description. elsewhere in the session description.
-.-.
In order to process the request successfully the PINT server must BOTH In order to process the request successfully the PINT server must BOTH
understand the attribute AND ALSO fulfil the request implied by the presence understand the attribute AND ALSO fulfil the request implied by the presence
of the attribute, for each attribute appearing within the attribute-list of of the attribute, for each attribute appearing within the attribute-list of
the require attribute. the require attribute.
If the server does not recognise the attribute listed, the PINT server MUST If the server does not recognise the attribute listed, the PINT server MUST
return an error status code (such as 420 (Bad Extension) or 400 (Bad return an error status code (such as 420 (Bad Extension) or 400 (Bad
Request)), Request)), and SHOULD return suitable Warning: lines explaining the problem
and SHOULD return suitable Warning: lines explaining the problem or an or an Unsupported: header containing the attribute it does not understand.
Unsupported: header containing the attribute it does not understand. If the If the server recognizes the attribute listed, but cannot fulfil the
server recognizes the attribute listed, but cannot fulfil the request implied request implied by the presence of the attribute, the request MUST fail
by the presence of the attribute, the request MUST fail with a status code with a status code of (606 Not Acceptable), along with a suitable
of (606 Not Acceptable), along with a suitable Unsupported: header or Unsupported: header or Warning: line.
Warning: line.
-.-.
The "require" attribute may appear anywhere in the session description, and The "require" attribute may appear anywhere in the session description, and
any number of times, but it MUST appear before the use of the attribute any number of times, but it MUST appear before the use of the attribute
marked as required. marked as required.
-.-.
Since the "require" attribute is itself an attribute, the SIP specification Since the "require" attribute is itself an attribute, the SIP specification
allows a server that does not understand the require attribute to ignore allows a server that does not understand the require attribute to ignore
it. In order to ensure that the PINT server will comply with the "require" it. In order to ensure that the PINT server will comply with the "require"
attribute, a PINT client should include a Require: header with the tag attribute, a PINT client should include a Require: header with the tag
"ietf.org.sdp.require" (section 3.5.4) "ietf.org.sdp.require" (section 3.5.4)
*-*-
Note that the majority of the PINT extensions are "tagged" and these tags Note that the majority of the PINT extensions are "tagged" and these tags
can be included in Require strictures. The exception is the use of phone can be included in Require strictures. The exception is the use of phone
numbers in SDP parts. However, these are defined as a new network and numbers in SDP parts. However, these are defined as a new network and
address type, so that a receiving SIP/SDP server should be able to detect address type, so that a receiving SIP/SDP server should be able to detect
whether or not it supports these forms. The default behaviour for any SDP whether or not it supports these forms. The default behaviour for any SDP
recipient is that it will fail a PINT request if it does not recognise or recipient is that it will fail a PINT request if it does not recognise or
support the TN and RFC2543 or X-token network and address types, as without support the TN and RFC2543 or X-token network and address types, as without
the contents being recognised no media session could be created. Thus a the contents being recognised no media session could be created. Thus a
separate stricture is not required in this case. separate stricture is not required in this case.
3.5. PINT Extensions to SIP 2.0 3.5. PINT Extensions to SIP 2.0
PINT requests are SIP requests; Many of the specifications within this PINT requests are SIP requests; Many of the specifications within this
document merely explain how to use existing SIP facilities for the purposes document merely explain how to use existing SIP facilities for the purposes
of PINT. of PINT.
*-*-
3.5.1. Multi-part MIME (sending data along with SIP request) 3.5.1. Multi-part MIME (sending data along with SIP request)
A PINT request can contain a payload which is multipart MIME. In this case A PINT request can contain a payload which is multipart MIME. In this case
the first part MUST contain an SDP session description that includes at the first part MUST contain an SDP session description that includes at
least one of the format specific attribute tags for "included content data" least one of the format specific attribute tags for "included content data"
specified above in section 3.4.3. All subsequent parts contain content data specified above in section 3.4.3. All subsequent parts contain content data
that is to be transferred to the requested Telephone Call Service. As that is to be transferred to the requested Telephone Call Service. As
discussed earlier, within a single PINT request, some of the data MAY be discussed earlier, within a single PINT request, some of the data MAY be
pointed to by a URI within the request, and some of the data MAY be included pointed to by a URI within the request, and some of the data MAY be included
within the request. within the request.
*-*-
Where included data is carried within a PINT service request, the Content Where included data is carried within a PINT service request, the Content
Type entity header of the enclosing SIP message MUST indicate this. To do Type entity header of the enclosing SIP message MUST indicate this. To do
so, the media type value within this entity header MUST be set to a value of so, the media type value within this entity header MUST be set to a value of
"multipart". "multipart".
The enclosed body parts SHOULD include the part-specific Content Type The enclosed body parts SHOULD include the part-specific Content Type
headers as appropriate ("application/sdp" for the first body part holding headers as appropriate ("application/sdp" for the first body part holding
the session description, with an appropriate content type for each of the the session description, with an appropriate content type for each of the
subsequent, "included data object" parts). This matches the standard syntax subsequent, "included data object" parts). This matches the standard syntax
of MIME multipart messages as defined in [4]. of MIME multipart messages as defined in [4].
skipping to change at page 23, line 18 skipping to change at page 23, line 17
Warning: 305 pint.acme.com Incompatible media format: jpeg Warning: 305 pint.acme.com Incompatible media format: jpeg
SIP servers that do not understand the PINT extensions at all are strongly SIP servers that do not understand the PINT extensions at all are strongly
encouraged to implement Warning: headers to indicate that PINT extensions encouraged to implement Warning: headers to indicate that PINT extensions
are not understood. are not understood.
Also, Warning: headers may be included within NOTIFY requests if it is Also, Warning: headers may be included within NOTIFY requests if it is
necessary to notify the client about some condition concerning the necessary to notify the client about some condition concerning the
invocation of the PINT service (see next). invocation of the PINT service (see next).
*-*-
3.5.3. Mechanism to register interest in the disposition of a PINT service, 3.5.3. Mechanism to register interest in the disposition of a PINT service,
and to receive indications on that disposition and to receive indications on that disposition
It can be very useful to find out whether or not a requested service has It can be very useful to find out whether or not a requested service has
completed, and if so whether or not it was successful. This is especially completed, and if so whether or not it was successful. This is especially
true for PINT service, where the person requesting the service is not true for PINT service, where the person requesting the service is not
(necessarily) a party to it, and so may not have an easy way of finding out (necessarily) a party to it, and so may not have an easy way of finding out
the disposition of that service. Equally, it may be useful to indicate when the disposition of that service. Equally, it may be useful to indicate when
the service has changed state, for example when the service call has the service has changed state, for example when the service call has
started. started.
Arranging a flexible system to provide extensive monitoring and control Arranging a flexible system to provide extensive monitoring and control
during a service is non-trivial (see section 6.4 for some issues); PINT 1.0 during a service is non-trivial (see section 6.4 for some issues); PINT 1.0
uses a simple scheme that should nevertheless provide useful information. It uses a simple scheme that should nevertheless provide useful information. It
is possible to expand the scheme in a "backwards compatible" manner, so if is possible to expand the scheme in a "backwards compatible" manner, so if
required it can be enhanced at a later date. Such enhancement would be required it can be enhanced at a later date. Such enhancement would be
expected to be the subject of a separate document. expected to be the subject of a separate document.
The PINT 1.0 status registration and indication scheme uses two new methods; The PINT 1.0 status registration and indication scheme uses three new
SUBSCRIBE and NOTIFY. These are used to allow a PINT Requesting entity to methods; SUBSCRIBE, UNSUBSCRIBE, and NOTIFY. These are used to allow a PINT
register an interest in (or "subscribe" to) the status of a service request, Requesting entity to register an interest in (or "subscribe" to) the status
and for the gateway to return service indications. Both of these messages of a service request, to indicate that this monitoring session is over,
and for the gateway to return service indications. All of these messages
follow the same procedure as used for all the SIP requests other than follow the same procedure as used for all the SIP requests other than
INVITE; the recipient MUST acknowledge the request with a final response INVITE; the recipient MUST acknowledge the request with a final response
message, otherwise the request will be repeated. message, otherwise the request will be repeated.
-.-.
3.5.3.1. Opening a monitoring session with a SUBSCRIBE request 3.5.3.1. Opening a monitoring session with a SUBSCRIBE request
The SUBSCRIBE request indicates that a user wishes to receive information The SUBSCRIBE request indicates that a user wishes to receive information
about the status of a session. The request identifies the session of interest about the status of a session. The request identifies the session of
normally by including the original session description along with the request. interest normally by including the original session description along
Where the subscription is being made by the user who initiated the original with the request. Where the subscription is being made by the user who
service request, the Call-ID may be used as it will be known to the receiver initiated the original service request, the Call-ID may be used as it
to refer to a previously established session. (When the request comes from a will be known to the receiver to refer to a previously established
user other than the original requesting user, the request constitutes a new session. (When the request comes from a user other than the original
call, so the Call-ID should not be used; instead the origin-field of the requesting user, the request constitutes a new SIP call leg, so the
session description enclosed within the original service request is used). Call-ID should not be used; instead the origin-field of the session
description enclosed within the original service request must be used).
The request MUST NOT include whatever content was present in the original The request MUST NOT include whatever content was present in the original
request other than the session description, and a server MUST ignore request other than the session description, and a server MUST ignore
whatever content is included within a SUBSCRIBE request with the sole whatever content is included within a SUBSCRIBE request with the sole
exception of the enclosed session description. exception of the enclosed session description.
-.-.
The request MAY contain a "Contact:" header, specifying the PINT User Agent The request MAY contain a "Contact:" header, specifying the PINT User Agent
Server to which such information should be sent. In addition, it SHOULD Server to which such information should be sent. In addition, it SHOULD
contain an Expires: header, which indicates for how long the PINT Requestor contain an Expires: header, which indicates for how long the PINT Requestor
wishes to receive notification of the session status. See section 5.1.4. wishes to receive notification of the session status. See section 5.1.4.
for security considerations, particularly privacy implications. for security considerations, particularly privacy implications.
A value of 0 within the Expires: header indicates a desire to receive one A value of 0 within the Expires: header indicates a desire to receive one
single immediate response (i.e. the request expires immediately). We refer single immediate response (i.e. the request expires immediately). We refer
to the period of time before the expiration of the SUBSCRIBE request as the to the period of time before the expiration of the SUBSCRIBE request as the
"subscription period". "subscription period".
skipping to change at page 24, line 34 skipping to change at page 24, line 33
Expires: header indicating how long it is willing to maintain the monitoring Expires: header indicating how long it is willing to maintain the monitoring
session. If this is unacceptable to the PINT Requestor, then it can close session. If this is unacceptable to the PINT Requestor, then it can close
the session by sending an immediate BYE (see 3.5.3.3). the session by sending an immediate BYE (see 3.5.3.3).
In principle, a user might send a SUBSCRIBE request after the telephone In principle, a user might send a SUBSCRIBE request after the telephone
network service has completed. This allows, for example, checking up "the network service has completed. This allows, for example, checking up "the
morning after" to see if the fax was successfully transmitted. However, a morning after" to see if the fax was successfully transmitted. However, a
PINT gateway is only required to keep state about a call for as long as it PINT gateway is only required to keep state about a call for as long as it
indicated previously in a Expires: header within the response to the indicated previously in a Expires: header within the response to the
original INVITE message that triggered the service session, within the original INVITE message that triggered the service session, within the
response to the SUBSCRIBE message, or within its BYE message (but see response to the SUBSCRIBE message, within the response to the BYE
section 3.5.8, point 3). message, or within its own BYE message (but see section 3.5.8, point 3).
If the Server no longer has a record of the session to which a Requestor has If the Server no longer has a record of the session to which a Requestor has
SUBSCRIBEd, it returns "606 Not Acceptable", along with the appropriate SUBSCRIBEd, it returns "606 Not Acceptable", along with the appropriate
Warning: 307 header indicating that the SDP session ID is no longer valid. Warning: 307 header indicating that the SDP session ID is no longer valid.
This means that a requesting Client that knows that it will want information This means that a requesting Client that knows that it will want information
about the status of a session after the session terminates SHOULD send a about the status of a session after the session terminates SHOULD send a
SUBSCRIBE request before the session terminates. SUBSCRIBE request before the session terminates.
3.5.3.2. Sending Status Indications with a NOTIFY request 3.5.3.2. Sending Status Indications with a NOTIFY request
During the subscription period, the Gateway may, from time to time, send a During the subscription period, the Gateway may, from time to time, send a
skipping to change at page 25, line 10 skipping to change at page 25, line 10
that situation it will immediately attempt to close the session (see next). that situation it will immediately attempt to close the session (see next).
The NOTIFY request contains the modified session description. For example, The NOTIFY request contains the modified session description. For example,
the Gateway may be able to indicate a more accurate start or stop time. the Gateway may be able to indicate a more accurate start or stop time.
The Gateway may include a Warning: header to describe some problem with the The Gateway may include a Warning: header to describe some problem with the
invocation of the service, and may indicate within an i= line some invocation of the service, and may indicate within an i= line some
information about the telephone network session itself. information about the telephone network session itself.
Example: Example:
NOTIFY sip:petrack@pager.com SIP/2.0 NOTIFY sip:petrack@pager.com SIP/2.0
To:sip:petrack@pager.com To:sip:petrack@pager.com
From:sip:R2F.pint.com@service.com From:sip:R2F.pint.com@service.com
Call-ID: 19971205T234505.56.78@pager.com
CSeq: 4711 SUBSCRIBE
Warning: xxx fax aborted, will try for the next hour. Warning: xxx fax aborted, will try for the next hour.
Content-Type:application/sdp Content-Type:application/sdp
c=... c=...
i=3 pages of 5 sent i=3 pages of 5 sent
t=... t=...
3..5.3.3. Closing a monitoring session with a BYE request 3.5.3.3. Closing a monitoring session with an UNSUBSCRIBE request
At some point, either the Client's representative User Agent Server or the At some point, either the Client's representative User Agent Server or the
Gateway may decide to terminate the monitoring session. This is achieved by Gateway may decide to terminate the monitoring session. This is achieved
sending a BYE request to the correspondent server. Such a request indicates by sending an UNSUBSCRIBE request to the correspondent server. Such a
that the sender intends to close the monitoring session immediately, and, on request indicates that the sender intends to close the monitoring session
receipt of the final response from the receiving server, the session is immediately, and, on receipt of the final response from the receiving
deemed over. server, the session is deemed over.
If the Gateway initiates closure of the monitoring session by sending a BYE If the Gateway initiates closure of the monitoring session by sending an
message, it SHOULD include an "Expires:" header showing for how much longer UNSUBSCRIBE message, it SHOULD include an "Expires:" header showing for
after this monitoring session is closed it is willing to store information how much longer after this monitoring session is closed it is willing to
on the service session. This acts as a minimum time within which the Client store information on the service session. This acts as a minimum time
can send a new SUBSCRIBE message to open another monitoring session; after within which the Client can send a new SUBSCRIBE message to open another
the time indicated in the Expires: header the Gateway is free to dispose of monitoring session; after the time indicated in the Expires: header the
any record of the service session, so that subsequent SUBSCRIBE requests can Gateway is free to dispose of any record of the service session, so that
be rejected with a "606" response. subsequent SUBSCRIBE requests can be rejected with a "606" response.
If the subscription period specified by the Client has expired, then the If the subscription period specified by the Client has expired, then the
Gateway may send an immediate BYE request to the Client's representative Gateway may send an immediate UNSUBSCRIBE request to the Client's
User Agent Server. This ensures that the monitoring session always completes representative User Agent Server. This ensures that the monitoring session
with a BYE/response exchange, and that the representative User Agent Server always completes with a UNSUBSCRIBE/response exchange, and that the
can avoid maintaining state in certain circumstances. representative User Agent Server can avoid maintaining state in certain
circumstances.
3.5.3.4. Timing of SUBSCRIBE requests 3.5.3.4. Timing of SUBSCRIBE requests
As it relies on the Gateway having a copy of the INVITEd session As it relies on the Gateway having a copy of the INVITEd session
description, the SUBSCRIBE message is limited in when it can be issued. The description, the SUBSCRIBE message is limited in when it can be issued. The
Gateway must have received the service request to which this monitoring Gateway must have received the service request to which this monitoring
session is to be associated, which from the Client's perspective happens as session is to be associated, which from the Client's perspective happens as
soon as the Gateway has sent a 1xx response back to it. soon as the Gateway has sent a 1xx response back to it.
However, once this has been done, there is no reason why the Client should However, once this has been done, there is no reason why the Client should
not send a monitoring request. It does not have to wait for the final not send a monitoring request. It does not have to wait for the final
response from the Gateway, and it can certainly send the SUBSCRIBE request response from the Gateway, and it can certainly send the SUBSCRIBE request
before sending the ACK for the Service request final response. Beyond this before sending the ACK for the Service request final response. Beyond this
skipping to change at page 26, line 30 skipping to change at page 26, line 30
immediately prior to sending an ACK message confirming the service if it is immediately prior to sending an ACK message confirming the service if it is
interested in transient service status messages. interested in transient service status messages.
3.5.4. The "Require:" header for PINT 3.5.4. The "Require:" header for PINT
PINT clients use the Require: header to signal to the PINT server that a PINT clients use the Require: header to signal to the PINT server that a
certain PINT extension of SIP is required. PINT 1.0 defines two strings that certain PINT extension of SIP is required. PINT 1.0 defines two strings that
can go into the Require header: can go into the Require header:
org.ietf.sip.subscribe -- the server can fulfill SUBSCRIBE requests org.ietf.sip.subscribe -- the server can fulfill SUBSCRIBE requests
(section 3.5.3) and associated methods (see section 3.5.3)
-.-.
org.ietf.sdp.require -- the PINT server (or the SDP parser associated org.ietf.sdp.require -- the PINT server (or the SDP parser associated
to it) understands the "require" attribute to it) understands the "require" attribute
defined in (section 3.4.4) defined in (section 3.4.4)
Example: Example:
-.-.
Require:org.ietf.sip.subscribe,org.ietf.sdp.require Require:org.ietf.sip.subscribe,org.ietf.sdp.require
A client should only include a Require: header where it truly requires the A client should only include a Require: header where it truly requires the
server to fail the request if the option is not supported. server to fail the request if the option is not supported.
3.5.5. PINT URLs within PINT requests 3.5.5. PINT URLs within PINT requests
Normally the hostnames and domain names that appear in the PINT URLs are the Normally the hostnames and domain names that appear in the PINT URLs are the
internal affair of each individual PINT system. A client uses the internal affair of each individual PINT system. A client uses the
appropriate SDP payload to indicate the particular service it wishes to appropriate SDP payload to indicate the particular service it wishes to
skipping to change at page 27, line 27 skipping to change at page 27, line 27
1. The user portion of a sip URL indicates the service to be requested. At 1. The user portion of a sip URL indicates the service to be requested. At
present the following services are defined: present the following services are defined:
R2C (for Request-to-Call) R2C (for Request-to-Call)
R2F (for Request-to-Fax) R2F (for Request-to-Fax)
R2HC (for Request-to-Hear-Content) R2HC (for Request-to-Hear-Content)
The user portions "R2C", "R2F", and "R2HC" are reserved for the PINT The user portions "R2C", "R2F", and "R2HC" are reserved for the PINT
milestone services. Other user portions MUST be used in case the requested milestone services. Other user portions MUST be used in case the requested
service is not one of the Milestone services. See section 3.5.8 for some service is not one of the Milestone services. See section 6.2 for some
related considerations concerning registrations by competing PINT systems to related considerations concerning registrations by competing PINT systems to
a single PINT proxy server acting as a service broker. a single PINT proxy server acting as a service broker.
2. The host portion of a sip URL contains the domain name of the PINT 2. The host portion of a sip URL contains the domain name of the PINT
service provider. service provider.
3. A new url-parameter is defined to be "tsp" (for "telephone service 3. A new url-parameter is defined to be "tsp" (for "telephone service
provider"). This can be used to indicate the actual telephone network provider"). This can be used to indicate the actual telephone network
provider to be used to fulfil the PINT request. provider to be used to fulfil the PINT request.
skipping to change at page 27, line 58 skipping to change at page 27, line 58
Any legal SIP URL can appear as a PINT URL within the Request-URI or To: Any legal SIP URL can appear as a PINT URL within the Request-URI or To:
header of a PINT request. But if the address is a telephone address, we header of a PINT request. But if the address is a telephone address, we
indicated in section 3.4.3 that it may be necessary to include more indicated in section 3.4.3 that it may be necessary to include more
information in order correctly to identify the remote telephone terminal or information in order correctly to identify the remote telephone terminal or
service. PINT clients MAY include these attribute tags within PINT URLs if service. PINT clients MAY include these attribute tags within PINT URLs if
they are necessary or a useful complement to the telephone number within the they are necessary or a useful complement to the telephone number within the
SIP URL. These attribute tags MUST be included as URL parameters as defined SIP URL. These attribute tags MUST be included as URL parameters as defined
in [1] (i.e. in the semi-colon separated manner). in [1] (i.e. in the semi-colon separated manner).
The following is an example of a PINT URL containing extra attribute tags: The following is an example of a PINT URL containing extra attribute tags:
-.-.
sip:+9725228808@pint.br.com;user=phone;require=Q763-plan;a=Q763-plan:4 sip:+9725228808@pint.br.com;user=phone;require=Q763-plan;a=Q763-plan:4
As we noted in section 3.4.3, these extra attribute parameters will not As we noted in section 3.4.3, these extra attribute parameters will not
normally be needed within a URL, because there is a great deal of context normally be needed within a URL, because there is a great deal of context
available to the help the server interpret the phone number correctly. In available to the help the server interpret the phone number correctly. In
particular, there is the SIP URL within the To: header, and there is also particular, there is the SIP URL within the To: header, and there is also
the Request-URI. In most cases this provides sufficient information for the the Request-URI. In most cases this provides sufficient information for the
telephone network. telephone network.
The SDP attributes defined in section 3 above will normally only be used The SDP attributes defined in section 3 above will normally only be used
when they are needed to supply necessary context to identify a telephone when they are needed to supply necessary context to identify a telephone
terminal. terminal.
3.5.7. REGISTER requests within PINT 3.5.7. REGISTER requests within PINT
*-*-
A PINT gateway is a SIP user agent server. A User Agent Server uses the A PINT gateway is a SIP user agent server. A User Agent Server uses the
REGISTER request to tell a proxy or redirect server that it is available to REGISTER request to tell a proxy or redirect server that it is available to
"receive calls" (i.e. to service requests). Thus a PINT Gateway registers "receive calls" (i.e. to service requests). Thus a PINT Gateway registers
with a proxy or redirect server the service that is accessible via itself, with a proxy or redirect server the service that is accessible via itself,
whilst in SIP, a user is registering his/her presence at a particular SIP whilst in SIP, a user is registering his/her presence at a particular SIP
Server. Server.
There may be competing PINT servers that can offer the same PINT service There may be competing PINT servers that can offer the same PINT service
trying to register at a single PINT server. The PINT server might act as a trying to register at a single PINT server. The PINT server might act as a
"broker" among the various PINT gateways that can fulfil a request. A "broker" among the various PINT gateways that can fulfil a request. A
skipping to change at page 29, line 37 skipping to change at page 29, line 37
description can be used to indicate the precise nature of the problem. description can be used to indicate the precise nature of the problem.
Example: Example:
SIP/2.0 606 Not Acceptable SIP/2.0 606 Not Acceptable
From: ... From: ...
To: ....... To: .......
..... .....
Warning: 399 pint.mycom.com Fax in progress, service cannot be aborted Warning: 399 pint.mycom.com Fax in progress, service cannot be aborted
Content-Type: application/sdp Content-Type: application/sdp
Content-Length: 50 Content-Length: ...
v=0 v=0
...
...
i=3 of 5 pages sent OK i=3 of 5 pages sent OK
c=TN RFC2543 +12014064090 c=TN RFC2543 +12014064090
m=image 1 fax tif m=image 1 fax tif
a=fmtp:tif uri:http://tifsRus.com/yyyyyy.tif a=fmtp:tif uri:http://tifsRus.com/yyyyyy.tif
Note that the server may return an updated session description within a Note that the server may return an updated session description within a
successful response to a BYE as well. This can be used, for example, to successful response to a BYE as well. This can be used, for example, to
indicate the actual start times and stop times of the telephone session, or indicate the actual start times and stop times of the telephone session, or
how many pages were sent in the fax transmission. how many pages were sent in the fax transmission.
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4. Examples of PINT Requests and Responses 4. Examples of PINT Requests and Responses
4.1. A request to a call centre from an anonymous user to receive a phone 4.1. A request to a call centre from an anonymous user to receive a phone
call. call.
C->S: INVITE sip:R2C@pint.mailorder.com SIP/2.0 C->S: INVITE sip:R2C@pint.mailorder.com SIP/2.0
Via: SIP/2.0/UDP 169.130.12.5 Via: SIP/2.0/UDP 169.130.12.5
From: sip:anon-1827631872@chinet.net From: sip:anon-1827631872@chinet.net
To: sip:+1-201-456-7890@iron.org;user=phone To: sip:+1-201-456-7890@iron.org;user=phone
Call-ID: 19971205T234505.56.78@chinet.net Call-ID: 19971205T234505.56.78@pager.com
CSeq: 4711 INVITE
Subject: Sale on Ironing Boards Subject: Sale on Ironing Boards
Content-type: application/sdp Content-type: application/sdp
Content-Length: ... Content-Length: 174
v=0 v=0
o=- 53655765 2353687637 IN IP4 128.3.4.5 o=- 2353687637 2353687637 IN IP4 128.3.4.5
s=R2C
i=Ironing Board Promotion i=Ironing Board Promotion
c= TN RFC2543 +1-201-406-4090 e=anon-1827631872@chinet.net
t=2353687637 0
m=audio 1 voice - m=audio 1 voice -
c=TN RFC2543 +1-201-406-4090
-.-.
In this example, the context that is required to interpret the To: address In this example, the context that is required to interpret the To: address
as a telephone number is not given explicitly; it is implicitly known to the as a telephone number is not given explicitly; it is implicitly known to the
R2C@pint.mailorder.com server. But the telephone of the person who wishes to R2C@pint.mailorder.com server. But the telephone of the person who wishes to
receive the call is explicitly identified as an internationally significant receive the call is explicitly identified as an internationally significant
E.164 number that falls within the North American numbering plan E.164 number that falls within the North American numbering plan
(because of the "+1" within the c= line). (because of the "+1" within the c= line).
4.2. A request from a non anonymous customer (John Jones) to receive a phone 4.2. A request from a non anonymous customer (John Jones) to receive a phone
call from a particular sales agent (Mary James) concerning the defective call from a particular sales agent (Mary James) concerning the defective
ironing board that was purchased ironing board that was purchased
C->S: INVITE sip:marketing@pint.mailorder.com SIP/2.0 C->S: INVITE sip:marketing@pint.mailorder.com SIP/2.0
Via: SIP/2.0/UDP 169.130.12.5 Via: SIP/2.0/UDP 169.130.12.5
From: sip:john.jones.3@chinet.net From: sip:john.jones.3@chinet.net
To: sip:mary.james@mailorder.com To: sip:mary.james@mailorder.com
Call-ID: 19971205T234505.56.79@chinet.net Call-ID: 19971205T234505.56.78@pager.com
CSeq: 4712 INVITE
Subject: Defective Ironing Board - want refund Subject: Defective Ironing Board - want refund
Content-type: application/sdp Content-type: application/sdp
Content-Length: ... Content-Length: 150
v=0 v=0
o=- 53655765 2353687637 IN IP4 128.3.4.5 o=- 2353687640 2353687640 IN IP4 128.3.4.5
s=marketing
e=john.jones.3@chinet.net
c= TN RFC2543 +1-201-406-4090 c= TN RFC2543 +1-201-406-4090
m=audio 1 voice t=2353687640 0
m=audio 1 voice -
The To: line might include the Mary James's phone number instead of a The To: line might include the Mary James's phone number instead of a
email-like address. An implementation that cannot accept email-like URLs in email-like address. An implementation that cannot accept email-like URLs in
the "To:" header must fail the request with a 606 Not Acceptable. the "To:" header must fail the request with a 606 Not Acceptable.
Note that the sending PINT client "knows" that the PINT Gateway contacted Note that the sending PINT client "knows" that the PINT Gateway contacted
with the "marketing@pint.mailorder.com" Request-URI is capable of processing with the "marketing@pint.mailorder.com" Request-URI is capable of processing
the client request as expected. (see 3.5.5.1 for a discussion on this). the client request as expected. (see 3.5.5.1 for a discussion on this).
Note also that such a telephone call service could be implemented on the Note also that such a telephone call service could be implemented on the
phone side with different details. For example, it might be that first the phone side with different details. For example, it might be that first the
skipping to change at page 31, line 41 skipping to change at page 31, line 45
indicated in "a=" attribute lines within the session description. The indicated in "a=" attribute lines within the session description. The
specification of such attribute lines for service consistency is beyond the specification of such attribute lines for service consistency is beyond the
scope of the PINT 1.0 specifications. scope of the PINT 1.0 specifications.
4.3. A request from the same user to get a fax back on how to assemble the 4.3. A request from the same user to get a fax back on how to assemble the
Ironing Board Ironing Board
C->S: INVITE sip:faxback@pint.mailorder.com SIP/2.0 C->S: INVITE sip:faxback@pint.mailorder.com SIP/2.0
Via: SIP/2.0/UDP 169.130.12.5 Via: SIP/2.0/UDP 169.130.12.5
From: sip:john.jones.3@chinet.net From: sip:john.jones.3@chinet.net
To: sip:1-800-FAXBACK@steam.edu;user=phone;phone-context=+1 To: sip:1-800-3292225K@steam.edu;user=phone;phone-context=+1
Call-ID: 19971205T234505.66.79@chinet.net Call-ID: 19971205T234505.66.79@chinet.net
CSeq: 4713 INVITE
Content-type: application/sdp Content-type: application/sdp
Content-Length: ... Content-Length: 218
v=0 v=0
o=- 53655768 2353687637 IN IP4 128.3.4.5 o=- 2353687660 2353687660 IN IP4 128.3.4.5
c= TN RFC2543 1-201-406-4091 s=faxback
e=john.jones.3@chinet.net
t=2353687660 0
m=application 1 fax URI m=application 1 fax URI
c=TN RFC2543 1-201-406-4091
a=fmtp:URI uri:http://localstore/Products/IroningBoards/2344.html a=fmtp:URI uri:http://localstore/Products/IroningBoards/2344.html
In this example, the fax to be sent is stored on some local server In this example, the fax to be sent is stored on some local server
(localstore), whose name may be only resolvable, or that may only be (localstore), whose name may be only resolvable, or that may only be
reachable, from within the IP network on which the PINT server sits. The reachable, from within the IP network on which the PINT server sits. The
phone number to be dialled is a "local phone number" as well. There is no phone number to be dialled is a "local phone number" as well. There is no
"phone-context" attribute, so the context (in this case, for which nation "phone-context" attribute, so the context (in this case, for which nation
the number is "nationally significant") must be supplied by the the number is "nationally significant") must be supplied by the
faxback@pint.mailorder.com PINT server. faxback@pint.mailorder.com PINT server.
-.-.
If the server that receives does not understand the number, it should fail If the server that receives does not understand the number, it should fail
the request with and include a "Network Address Not Understood" warning. the request with and include a "Network Address Not Understood" warning.
Note that no "require" attribute was used here, since it is very likely Note that no "require" attribute was used here, since it is very likely
that the request can be serviced even by a server that does not support that the request can be serviced even by a server that does not support
the "require" attribute. the "require" attribute.
4.4. A request from same user to have that same information read out over 4.4. A request from same user to have that same information read out over
the phone the phone
C->S: INVITE sip:faxback@pint.mailorder.com SIP/2.0 C->S: INVITE sip:faxback@pint.mailorder.com SIP/2.0
Via: SIP/2.0/UDP 169.130.12.5 Via: SIP/2.0/UDP 169.130.12.5
From: john.jones.3@chinet.net From: sip:john.jones.3@chinet.net
To: sip:1-800-FAXBACK@steam.edu;user=phone;phone-context=+1 To: sip:1-800-3292225@steam.edu;user=phone;phone-context=+1
Call-ID: 19971205T234505.66.79@chinet.net Call-ID: 19971205T234505.66.79@chinet.net
CSeq: 4713 INVITE
Content-type: application/sdp Content-type: application/sdp
Content-Length: ... Content-Length: 220
v=0 v=0
o=- 53655768 2353687637 IN IP4 128.3.4.5 o=- 2353687660 2353687660 IN IP4 128.3.4.5
c= TN RFC2543 +1-201-406-4090 s=faxback
e=john.jones.3@chinet.net
t=2353687660 0
m=application 1 voice URI m=application 1 voice URI
c=TN RFC2543 1-201-406-4090
a=fmtp:URI uri:http://localstore/Products/IroningBoards/2344.html a=fmtp:URI uri:http://localstore/Products/IroningBoards/2344.html
4.5. A request to send an included text page to a friend's pager. 4.5. A request to send an included text page to a friend's pager.
In this example, the text to be paged out is included in the request. In this example, the text to be paged out is included in the request.
C->S: INVITE sip:R2F@pint.pager.com SIP/2.0 C->S: INVITE sip:R2F@pint.pager.com SIP/2.0
Via: SIP/2.0/UDP 169.130.12.5 Via: SIP/2.0/UDP 169.130.12.5
From: scott.petrack@chinet.net From: sip:scott.petrack@chinet.net
To: sip:R2F@pint.pager.com To: sip:R2F@pint.pager.com
Call-ID: 19974505.66.79@chinet.net Call-ID: 19974505.66.79@chinet.net
CSeq: 4714 INVITE
Content-Type: multipart/mixed; boundary=--next Content-Type: multipart/mixed; boundary=--next
----next ----next
Content-Type: application/sdp Content-Type: application/sdp
Content-Length: ... Content-Length: 236
v=0 v=0
o=- 53655768 2353687637 IN IP4 128.3.4.5 o=- 2353687680 2353687680 IN IP4 128.3.4.5
c= TN RFC2543 +972-9-956-1867 s=R2F
e=scott.petrack@chinet.net
t=2353687680 0
m=text 1 pager plain m=text 1 pager plain
c= TN RFC2543 +972-9-956-1867
a=fmtp:plain spr:2@53655768 a=fmtp:plain spr:2@53655768
----next ----next
Content-Type: text/plain Content-Type: text/plain
Content-ID: 2@53655768 Content-ID: 2@53655768
Content-Length:... Content-Length:50
Hi Joe! Please call me asap at 555-1234. Hi Joe! Please call me asap at 555-1234.
----next-- ----next--
4.6. A request to send an image as a fax to phone number +972-9-956-1867 4.6. A request to send an image as a fax to phone number +972-9-956-1867
C->S: INVITE sip:faxserver@pint.vocaltec.com SIP/2.0 C->S: INVITE sip:faxserver@pint.vocaltec.com SIP/2.0
Via: SIP/2.0/UDP 169.130.12.5 Via: SIP/2.0/UDP 169.130.12.5
From: scott.petrack@chinet.net From: sip:scott.petrack@chinet.net
To: sip:faxserver@pint.vocaltec.com To: sip:faxserver@pint.vocaltec.com
Call-ID: 19971205T234505.66.79@chinet.net Call-ID: 19971205T234505.66.79@chinet.net
CSeq: 4715 INVITE
Content-type: application/sdp Content-type: application/sdp
Content-Length: ... Content-Length: 267
v=0 v=0
o=- 53655768 2353687637 IN IP4 128.3.4.5 o=- 2353687700 2353687700 IN IP4 128.3.4.5
c= TN RFC2543 +972-9-956-1867 s=faxserver
e=scott.petrack@chinet.net
t=2353687700 0
m=image 1 fax tif gif m=image 1 fax tif gif
c= TN RFC2543 +972-9-956-1867
a=fmtp:tif uri:http://petrack/images/tif/picture1.tif a=fmtp:tif uri:http://petrack/images/tif/picture1.tif
a=fmtp:gif uri:http://petrack/images/gif/picture1.gif a=fmtp:gif uri:http://petrack/images/gif/picture1.gif
-.-.
The image is available as tif or as gif. The tif is the preferred format. The image is available as tif or as gif. The tif is the preferred format.
Note that the http server where the pictures reside is local, and the PINT Note that the http server where the pictures reside is local, and the PINT
server is also local (because it can resolve machine name "petrack") server is also local (because it can resolve machine name "petrack")
4.7. A request to read out over the phone two pieces of content in sequence. 4.7. A request to read out over the phone two pieces of content in sequence.
First some included text is read out by text-to-speech. Then some text that First some included text is read out by text-to-speech. Then some text that
is stored at some URI on the internet is read out. is stored at some URI on the internet is read out.
C->S: INVITE sip:R2HC@pint.acme.com SIP/2.0 C->S: INVITE sip:R2HC@pint.acme.com SIP/2.0
Via: SIP/2.0/UDP 169.130.12.5 Via: SIP/2.0/UDP 169.130.12.5
From: scott.petrack@chinet.net From: sip:scott.petrack@chinet.net
To: sip:R2HC@pint.acme.com To: sip:R2HC@pint.acme.com
Call-ID: 19974505.66.79@chinet.net Call-ID: 19974505.66.79@chinet.net
CSeq: 4716 INVITE
Content-Type: multipart/mixed; boundary=next Content-Type: multipart/mixed; boundary=next
--next --next
Content-Type: application/sdp Content-Type: application/sdp
Content-Length: ... Content-Length: 316
v=0 v=0
o=- 53655768 2353687637 IN IP4 128.3.4.5 o=- 2353687720 2353687720 IN IP4 128.3.4.5
s=R2HC
e=scott.petrack@chinet.net
c= TN RFC2543 +1-201-406-4091 c= TN RFC2543 +1-201-406-4091
t=2353687720 0
m=text 1 voice plain m=text 1 voice plain
a=fmtp:plain spr:2@53655768 a=fmtp:plain spr:2@53655768
m=text 1 voice plain m=text 1 voice plain
a=fmtp:plain uri:http://www.your.com/texts/stuff.doc a=fmtp:plain uri:http://www.your.com/texts/stuff.doc
--next --next
Content-Type: text/plain Content-Type: text/plain
Content-ID: 2@53655768 Content-ID: 2@53655768
Content-Length: ... Content-Length: 172
Hello!! I am about to read out to you the document you Hello!! I am about to read out to you the document you
requested, "uri:http://www.your.com/texts/stuff.doc". requested, "uri:http://www.your.com/texts/stuff.doc".
We hope you like acme.com's new speech synthesis server. We hope you like acme.com's new speech synthesis server.
--next-- --next--
*-*-
4.8. Request for the prices for ISDN to be sent to my fax machine 4.8. Request for the prices for ISDN to be sent to my fax machine
INVITE sip:R2FB@pint.bt.co.uk SIP/2.0 INVITE sip:R2FB@pint.bt.co.uk SIP/2.0
Via: SIP/2.0/UDP 169.130.12.5 Via: SIP/2.0/UDP 169.130.12.5
To:0345-12347-01;user=phone;phone-context=+44 To: sip:0345-12347-01@pint.bt.co.uk;user=phone;phone-context=+44
From: sip:hank.wangford@newts.demon.co.uk From: sip:hank.wangford@newts.demon.co.uk
Call-ID: 19981204T201505.56.78@demon.co.uk Call-ID: 19981204T201505.56.78@demon.co.uk
CSeq: 4716 INVITE
Subject: Price List Subject: Price List
Content-type: application/sdp Content-type: application/sdp
Content-Length: 116 Content-Length: 169
v=0 v=0
o=-53655765 2353687637 IN IP4 128.3.4.5 o=- 2353687740 2353687740 IN IP4 128.3.4.5
s=R2FB
i=ISDN Price List i=ISDN Price List
c=TN RFC2543 +44-1794-8331010 e=hank.wangford@newts.demon.co.uk
t=2353687740 0
m=text 1 fax - m=text 1 fax -
c=TN RFC2543 +44-1794-8331010
4.9. Request for a callback 4.9. Request for a callback
INVITE sip:R2C@pint.bt.co.uk SIP/2.0 INVITE sip:R2C@pint.bt.co.uk SIP/2.0
Via: SIP/2.0/UDP 169.130.12.5 Via: SIP/2.0/UDP 169.130.12.5
To:0345-123456;user=phone;phone-context=+44 To: sip:0345-123456@pint.bt.co.uk;user=phone;phone-context=+44
From: sip:hank.wangford@newts.demon.co.uk From: sip:hank.wangford@newts.demon.co.uk
Call-ID: 19981204T234505.56.78@demon.co.uk Call-ID: 19981204T234505.56.78@demon.co.uk
CSeq: 4717 INVITE
Subject: It costs HOW much? Subject: It costs HOW much?
Content-type: application/sdp Content-type: application/sdp
Content-Length: 123 Content-Length: 176
v=0 v=0
o=- 53655765 2353687637 IN IP4 128.3.4.5 o=- 2353687760 2353687760 IN IP4 128.3.4.5
s=R2C
i=ISDN pre-sales query i=ISDN pre-sales query
e=hank.wangford@newts.demon.co.uk
c= TN RFC2543 +44-1794-8331013 c= TN RFC2543 +44-1794-8331013
t=2353687760 0
m=audio 1 voice - m=audio 1 voice -
4.10.Sending a set of information in response to an enquiry 4.10.Sending a set of information in response to an enquiry
INVITE sip:R2FB@pint.bt.co.uk SIP/2.0 INVITE sip:R2FB@pint.bt.co.uk SIP/2.0
Via: SIP/2.0/UDP 169.130.12.5 Via: SIP/2.0/UDP 169.130.12.5
To:0345-12347-01;user=phone;phone-context=+44 To: sip:0345-12347-01@pint.bt.co.uk;user=phone;phone-context=+44
From: sip:colin.masterton@sales.hh.bt.co.uk From: sip:colin.masterton@sales.hh.bt.co.uk
Call-ID: 19981205T234505.56.78@sales.hh.bt.co.uk Call-ID: 19981205T234505.56.78@sales.hh.bt.co.uk
CSeq: 1147 INVITE
Subject: Price Info, as requested Subject: Price Info, as requested
Content-Type: multipart/mixed; boundary=next Content-Type: multipart/mixed; boundary=next
--next --next
Content-type: application/sdp Content-type: application/sdp
Content-Length: 211 Content-Length: 325
v=0 v=0
o=-53655765 2353687637 IN IP4 128.3.4.5 o=- 2353687780 2353687780 IN IP4 128.3.4.5
s=R2FB
i=Your documents i=Your documents
c=TN RFC2543 +44-1794-8331010 e=colin.masterton@sales.hh.bt.co.uk
t=2353687780 0
m=application 1 fax octet-stream m=application 1 fax octet-stream
c=TN RFC2543 +44-1794-8331010
a=fmtp:octet-stream uri:http://www.bt.co.uk/imgs/pipr.gif opr: a=fmtp:octet-stream uri:http://www.bt.co.uk/imgs/pipr.gif opr:
spr:2@53655768 spr:2@53655768
--next --next
Content-Type: text/plain Content-Type: text/plain
Content-ID: 2@53655768 Content-ID: 2@53655768
Content-Length: 352 Content-Length: 352
Dear Sir, Dear Sir,
Thank you for your enquiry. I have checked availability in your Thank you for your enquiry. I have checked availability in your
area, and we can provide service to your cottage. I enclose a quote area, and we can provide service to your cottage. I enclose a quote
for the costs of installation, together with the ongoing rental for the costs of installation, together with the ongoing rental
costs for the line. If you want to proceed with this, please quote costs for the line. If you want to proceed with this, please quote
skipping to change at page 35, line 24 skipping to change at page 35, line 50
job reference isdn/hh/123.45.9901. job reference isdn/hh/123.45.9901.
Yours Sincerely, Yours Sincerely,
Colin Masterton Colin Masterton
--next-- --next--
Note that the "implicit" faxback content is given by an EMPTY opaque Note that the "implicit" faxback content is given by an EMPTY opaque
reference in the middle of the fmtp line in this example. reference in the middle of the fmtp line in this example.
4.11.Sportsline "headlines" message sent to your phone/pager/fax 4.11.Sportsline "headlines" message sent to your phone/pager/fax
(i) phone (i) phone
INVITE sip:R2FB@pint.wwos.skynet.com SIP/2.0 INVITE sip:R2FB@pint.wwos.skynet.com SIP/2.0
Via: SIP/2.0/UDP 169.130.12.5 Via: SIP/2.0/UDP 169.130.12.5
To:1-900-123-456-7;user=phone;phone-context=+1 To: sip:1-900-123-456-7@wwos.skynet.com;user=phone;phone-context=+1
From: sip:fred.football.fan@skynet.com From: sip:fred.football.fan@skynet.com
Call-ID: 19971205T234505.56.78@chinet.net Call-ID: 19971205T234505.56.78@chinet.net
CSeq: 4721 INVITE
Subject: Wonderful World Of Sports NFL Final Scores Subject: Wonderful World Of Sports NFL Final Scores
Content-type: application/sdp Content-type: application/sdp
Content-Length: 174 Content-Length: 220
v=0 v=0
o=- 53655765 2353687637 IN IP4 128.3.4.5 o=- 2353687800 2353687800 IN IP4 128.3.4.5
s=R2FB
i=NFL Final Scores i=NFL Final Scores
e=fred.football.fan@skynet.com
c= TN RFC2543 +44-1794-8331013 c= TN RFC2543 +44-1794-8331013
t=2353687800 0
m=audio 1 voice x-pay m=audio 1 voice x-pay
a=fmtp:x-pay opr:mci.com/md5:<crypto signature> a=fmtp:x-pay opr:mci.com/md5:<crypto signature>
(ii) fax (ii) fax
INVITE sip:R2FB@pint.wwos.skynet.com SIP/2.0 INVITE sip:R2FB@pint.wwos.skynet.com SIP/2.0
Via: SIP/2.0/UDP 169.130.12.5 Via: SIP/2.0/UDP 169.130.12.5
To:1-900-123-456-7;user=phone;phone-context=+1 To: sip:1-900-123-456-7@wwos.skynet.com;user=phone;phone-context=+1
From: sip:fred.football.fan@skynet.com From: sip:fred.football.fan@skynet.com
Call-ID: 19971205T234505.56.78@chinet.net Call-ID: 19971205T234505.56.78@chinet.net
CSeq: 4722 INVITE
Subject: Wonderful World Of Sports NFL Final Scores Subject: Wonderful World Of Sports NFL Final Scores
Content-type: application/sdp Content-type: application/sdp
Content-Length: 173 Content-Length: 217
v=0 v=0
o=- 53655765 2353687637 IN IP4 128.3.4.5 o=- 2353687820 2353687820 IN IP4 128.3.4.5
s=R2FB
i=NFL Final Scores i=NFL Final Scores
e=fred.football.fan@skynet.com
c= TN RFC2543 +44-1794-8331010 c= TN RFC2543 +44-1794-8331010
t=2353687820 0
m=text 1 fax x-pay m=text 1 fax x-pay
a=fmtp:x-pay opr:mci.com/md5:<crypto signature> a=fmtp:x-pay opr:mci.com/md5:<crypto signature>
(iii) pager (iii) pager
INVITE sip:R2FB@pint.wwos.skynet.com SIP/2.0 INVITE sip:R2FB@pint.wwos.skynet.com SIP/2.0
Via: SIP/2.0/UDP 169.130.12.5 Via: SIP/2.0/UDP 169.130.12.5
To:1-900-123-456-7;user=phone;phone-context=+1 To: sip:1-900-123-456-7@wwos.skynet.com;user=phone;phone-context=+1
From: sip:fred.football.fan@skynet.com From: sip:fred.football.fan@skynet.com
Call-ID: 19971205T234505.56.78@chinet.net Call-ID: 19971205T234505.56.78@chinet.net
CSeq: 4723 INVITE
Subject: Wonderful World Of Sports NFL Final Scores Subject: Wonderful World Of Sports NFL Final Scores
Content-type: application/sdp Content-type: application/sdp
Content-Length: 173 Content-Length: 219
v=0 v=0
o=- 53655765 2353687637 IN IP4 128.3.4.5 o=- 2353687840 2353687840 IN IP4 128.3.4.5
s=R2FB
i=NFL Final Scores i=NFL Final Scores
e=fred.football.fan@skynet.com
c= TN RFC2543 +44-1794-8331015 c= TN RFC2543 +44-1794-8331015
t=2353687840 0
m=text 1 pager x-pay m=text 1 pager x-pay
a=fmtp:x-pay opr:mci.com/md5:<crypto signature> a=fmtp:x-pay opr:mci.com/md5:<crypto signature>
Note that these are all VERY similar. Note that these are all VERY similar.
4.12.Automatically giving someone a fax copy of your phone bill 4.12.Automatically giving someone a fax copy of your phone bill
INVITE sip:BillsRUs@pint.sprint.com SIP/2.0 INVITE sip:BillsRUs@pint.sprint.com SIP/2.0
Via: SIP/2.0/UDP 169.130.12.5 Via: SIP/2.0/UDP 169.130.12.5
To:+1-555-888-1234;user=phone To: sip:+1-555-888-1234@fbi.gov;user=phone
From: sip:agent.mulder@fbi.gov From: sip:agent.mulder@fbi.gov
Call-ID: 19991231T234505.56.78@fbi.gov Call-ID: 19991231T234505.56.78@fbi.gov
CSeq: 911 INVITE
Subject: Itemised Bill for January 98 Subject: Itemised Bill for January 98
Content-type: application/sdp Content-type: application/sdp
Content-Length: 117 Content-Length: 247
v=0 v=0
o=-53655765 2353687637 IN IP4 128.3.4.5 o=- 2353687860 2353687860 IN IP4 128.3.4.5
s=BillsRUs
i=Joe Pendleton's Phone Bill i=Joe Pendleton's Phone Bill
e=agent.mulder@fbi.gov
c=TN RFC2543 +1-202-833-1010 c=TN RFC2543 +1-202-833-1010
t=2353687860 0
m=text 1 fax x-files-id m=text 1 fax x-files-id
a=fmtp:x-files-id opr:fbi.gov/jdcn-123@45:3des;base64,<signature> a=fmtp:x-files-id opr:fbi.gov/jdcn-123@45:3des;base64,<signature>
Note: in this case the opaque reference is data used to convince the Note: in this case the opaque reference is data used to convince the
Executive System that the requester has the right to get this information, Executive System that the requester has the right to get this information,
rather than selecting the particular content (the A party in the To: field rather than selecting the particular content (the A party in the To: field
of the SIP "wrapper" does that alone). of the SIP "wrapper" does that alone).
5. Security Considerations 5. Security Considerations
5.1. Basic Principles for PINT Use 5.1. Basic Principles for PINT Use
A PINT Gateway, and the Executive System(s) with which that Gateway is A PINT Gateway, and the Executive System(s) with which that Gateway is
associated, exist to provide service to PINT Requestors. The aim of the PINT associated, exist to provide service to PINT Requestors. The aim of the PINT
protocol is to pass requests from those users on to a PINT Gateway so an protocol is to pass requests from those users on to a PINT Gateway so an
associated Executive System can service those requests. associated Executive System can service those requests.
5.1.1. Responsibility for service requests 5.1.1. Responsibility for service requests
The facility of making a PSTN-based call to numbers specified in the PINT The facility of making a GSTN-based call to numbers specified in the PINT
request, however, comes with some risks. The request can specify an incorrect request, however, comes with some risks. The request can specify an incorrect
telephone of fax number. It is also possible that the Requestor has purposely telephone of fax number. It is also possible that the Requestor has purposely
entered the telephone number of an innocent third party. Finally, the request entered the telephone number of an innocent third party. Finally, the request
may have been intercepted on its way through any intervening PINT or SIP may have been intercepted on its way through any intervening PINT or SIP
infrastructure, and the request may have been altered. infrastructure, and the request may have been altered.
In any of these cases, the result may be that a call is placed incorrectly. In any of these cases, the result may be that a call is placed incorrectly.
Where there is intent or negligence, this may be construed as harrasment of Where there is intent or negligence, this may be construed as harrasment of
the person incorrectly receiving the call. Whilst the regulatory framework for the person incorrectly receiving the call. Whilst the regulatory framework for
misuse of Internet connections differs throughout the world and is not always misuse of Internet connections differs throughout the world and is not always
mature, the rules under which PSTN calls are made are much more settled. mature, the rules under which GSTN calls are made are much more settled.
Someone may be liable for mistaken or incorrect calls. Someone may be liable for mistaken or incorrect calls.
Understandably, the PSTN Operators would prefer that this someone is not them, Understandably, the GSTN Operators would prefer that this someone is not them,
so they will need to ensure that any PINT Gateway and Executive System so they will need to ensure that any PINT Gateway and Executive System
combination does not generate incorrect calls through some error in the combination does not generate incorrect calls through some error in the
Gateway or Executive system implementation or PSTN-internal communications Gateway or Executive system implementation or GSTN-internal communications
fault. Equally, it is important that the Operator can show that they act only fault. Equally, it is important that the Operator can show that they act only
on requests that they have good reason to believe are correct. This means that on requests that they have good reason to believe are correct. This means that
the Gateway must not pass on requests unless it is sure that they have not the Gateway must not pass on requests unless it is sure that they have not
been corrupted in transit from the Requestor. been corrupted in transit from the Requestor.
If a request can be shown to have come from a particular Requestor and to have If a request can be shown to have come from a particular Requestor and to have
been acted on in good faith by the PINT service provider, then responsibility been acted on in good faith by the PINT service provider, then responsibility
for making requests may well fall to the Requestor rather than the Operator for making requests may well fall to the Requestor rather than the Operator
who executed these requests. who executed these requests.
Finally, it may be important for the PINT service provider to be able to show Finally, it may be important for the PINT service provider to be able to show
that they act only on requests for which they have some degree of assurance of that they act only on requests for which they have some degree of assurance of
origin. In many jurisdictions, it is a requirement on PSTN Operators that they origin. In many jurisdictions, it is a requirement on GSTN Operators that they
place calls only when they can, if required, identify the parties to the call place calls only when they can, if required, identify the parties to the call
(such as when required to carry out a Malicious Call Trace). It is at least (such as when required to carry out a Malicious Call Trace). It is at least
likely that the provider of PINT services will have a similar responsibility likely that the provider of PINT services will have a similar responsibility
placed on them. placed on them.
-.-.
It follows that the PINT service provider may require that the identity of the It follows that the PINT service provider may require that the identity of the
Requestor be confirmed. If such confirmation is not available, then they may Requestor be confirmed. If such confirmation is not available, then they may
be forced (or choose) not to provide service. This identification will require be forced (or choose) not to provide service. This identification will require
personal authentication of the Requesting User. personal authentication of the Requesting User.
5.1.2. Authority to make requests 5.1.2. Authority to make requests
Where PSTN resources are used to provide a PINT service, it is at least Where GSTN resources are used to provide a PINT service, it is at least
possible that someone will have to pay for it. This person may not be the possible that someone will have to pay for it. This person may not be the
Requestor, as, for example, in the case of existing PSTN split-charging Requestor, as, for example, in the case of existing GSTN split-charging
services like free phone in which the recipient of a call rather than the services like free phone in which the recipient of a call rather than the
originator is responsible for the call cost. originator is responsible for the call cost.
This is not, of course, the only possibility; for example, PINT service may be This is not, of course, the only possibility; for example, PINT service may be
provided on a subscription basis, and there are a number of other models. provided on a subscription basis, and there are a number of other models.
However, whichever model is chosen, there may be a requirement that the However, whichever model is chosen, there may be a requirement that the
authority of a Requestor to make a PINT request is confirmed. authority of a Requestor to make a PINT request is confirmed.
If such confirmation is not available, then, again, the PINT Gateway and If such confirmation is not available, then, again, the PINT Gateway and
associated Executive System may choose not to provide service. associated Executive System may choose not to provide service.
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be carried within that request. This can be sensitive information, as an be carried within that request. This can be sensitive information, as an
eavesdropper might steal this and use it within their own requests. Such eavesdropper might steal this and use it within their own requests. Such
authority should be treated as if it were financial information (such as a authority should be treated as if it were financial information (such as a
credit card number or PIN). credit card number or PIN).
The data authorizing a Requesting User to make a PINT request should be known The data authorizing a Requesting User to make a PINT request should be known
only to them and the service provider. However, this information may be in a only to them and the service provider. However, this information may be in a
form that does not match the schemes normally used within the Internet. For form that does not match the schemes normally used within the Internet. For
example, X.509 certificates[14] are commonly used for secured transactions on example, X.509 certificates[14] are commonly used for secured transactions on
the Internet both in the IP Security Architecture[12] and in the TLS the Internet both in the IP Security Architecture[12] and in the TLS
protocol[13], but the PSTN provider may only store an account code and PIN protocol[13], but the GSTN provider may only store an account code and PIN
(i.e. a fixed string of numbers). (i.e. a fixed string of numbers).
-.-.
A Requesting User has a reasonable expectation that their requests for service A Requesting User has a reasonable expectation that their requests for service
are confidential. For some PINT services, no content data is carried over the are confidential. For some PINT services, no content data is carried over the
Internet; however, the telephone or fax numbers of the parties to a resulting Internet; however, the telephone or fax numbers of the parties to a resulting
service calls may be considered sensitive. As a result, it is likely that the service calls may be considered sensitive. As a result, it is likely that the
Requestor (and their PINT service provider) will require that any request that Requestor (and their PINT service provider) will require that any request that
is sent across the Internet be protected against eavesdroppers; in short, the is sent across the Internet be protected against eavesdroppers; in short, the
requests should to be encrypted. requests should to be encrypted.
-.-.
5.1.4. Privacy Implications of SUBSCRIBE/NOTIFY 5.1.4. Privacy Implications of SUBSCRIBE/NOTIFY
Some special considerations relate to monitoring sessions using the SUBSCRIBE Some special considerations relate to monitoring sessions using the SUBSCRIBE
and NOTIFY messages. The SUBSCRIBE message that is used to register an and NOTIFY messages. The SUBSCRIBE message that is used to register an
interest in the disposition of a PINT service transaction uses the original interest in the disposition of a PINT service transaction uses the original
Session Description carried in the related INVITE message. This current Session Description carried in the related INVITE message. This current
specification does not restrict the source of such a SUBSCRIBE message, so it specification does not restrict the source of such a SUBSCRIBE message, so it
is possible for an eavesdropper to capture an unprotected sesssion description is possible for an eavesdropper to capture an unprotected session description
and use this in a subsequent SUBSCRIBE request. In this way it is possible to and use this in a subsequent SUBSCRIBE request. In this way it is possible to
find out details on that transaction that may well be considered sensitive. find out details on that transaction that may well be considered sensitive.
The initial solution to this risk is to recommend that a session description The initial solution to this risk is to recommend that a session description
that may be used within a subsequent SUBSCRIBE message SHOULD be protected. that may be used within a subsequent SUBSCRIBE message SHOULD be protected.
However, there is a further risk; if the origin-field used is "guessable" then However, there is a further risk; if the origin-field used is "guessable" then
it might be possible for an attacker to reconstruct the session description it might be possible for an attacker to reconstruct the session description
and use this reconstruction within a SUBSCRIBE message. and use this reconstruction within a SUBSCRIBE message.
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0. It is important that a PINT Registrar uses authentication of the 0. It is important that a PINT Registrar uses authentication of the
Registrand, as otherwise one PINT service provider would be able to "spoof" Registrand, as otherwise one PINT service provider would be able to "spoof"
another and remove their registration. As this would stop the Proxy passing another and remove their registration. As this would stop the Proxy passing
any requests to that provider, this would both increase requests being sent to any requests to that provider, this would both increase requests being sent to
the rogue and stop requests going to the victim. the rogue and stop requests going to the victim.
Another variant on this attack would be to register a Gateway using a name Another variant on this attack would be to register a Gateway using a name
that has been registered by another provider; thus a rogue Operator might that has been registered by another provider; thus a rogue Operator might
register its Gateway as "R2C@pint.att.com", thereby hijacking requests. register its Gateway as "R2C@pint.att.com", thereby hijacking requests.
-.-.
The solution is the same; all registrations by PINT Gateways MUST be The solution is the same; all registrations by PINT Gateways MUST be
authenticated; this includes both new or apparent replacement registrations, authenticated; this includes both new or apparent replacement registrations,
and any cancellation of current registrations. This recommendation is also and any cancellation of current registrations. This recommendation is also
made in the SIP specification, but for the correct operation of PINT, it is made in the SIP specification, but for the correct operation of PINT, it is
very important indeed. very important indeed.
5.3. Security mechanisms and implications on PINT service 5.3. Security mechanisms and implications on PINT service
PINT is a set of extensions to SIP[1] and SDP[2], and will use the security PINT is a set of extensions to SIP[1] and SDP[2], and will use the security
procedures described in SIP. There are several implications of this, and these procedures described in SIP. There are several implications of this, and these
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address, such as a Call Centre. address, such as a Call Centre.
Another aspect of this is that, even if the Requesting User does not consider Another aspect of this is that, even if the Requesting User does not consider
the telephone or fax numbers of the parties to a PINT service to be private, the telephone or fax numbers of the parties to a PINT service to be private,
those parties might. Where PINT servers have reason to believe this might be those parties might. Where PINT servers have reason to believe this might be
the case they SHOULD encrypt the request, even if the Requestor has not done the case they SHOULD encrypt the request, even if the Requestor has not done
so. This could happen, for example, if a Requesting User within a company so. This could happen, for example, if a Requesting User within a company
placed a PINT request and this was carried via the company's Intranet to their placed a PINT request and this was carried via the company's Intranet to their
Proxy/firewall and thence over the Internet to a PINT Gateway at another Proxy/firewall and thence over the Internet to a PINT Gateway at another
location. location.
-.-.
If a request carries data that can be reused by an eavesdropper either to If a request carries data that can be reused by an eavesdropper either to
"spoof" the Requestor or to obtain PINT service by inserting the Requestor's "spoof" the Requestor or to obtain PINT service by inserting the Requestor's
authorization token into an eavesdropper's request, then this data MUST be authorization token into an eavesdropper's request, then this data MUST be
protected. This is particularly important if the authorization token consists protected. This is particularly important if the authorization token consists
of static text (such as an account code and/or PIN). of static text (such as an account code and/or PIN).
-.-.
One approach is to encrypt the whole of the request, using the methods One approach is to encrypt the whole of the request, using the methods
described in the SIP specification. As an alternative, it may be acceptable described in the SIP specification. As an alternative, it may be acceptable
for the authorization token to be held as an opaque reference (see section for the authorization token to be held as an opaque reference (see section
3.4.2.3 and examples 4.11 and 4.12), using some proprietary scheme agreed 3.4.2.3 and examples 4.11 and 4.12), using some proprietary scheme agreed
between the Requestor and the PINT service provider, as long as this is between the Requestor and the PINT service provider, as long as this is
resistant to interception and re-use. Also, it may be that the authorization resistant to interception and re-use. Also, it may be that the authorization
token cannot be used outside of a request cryptographically signed by the token cannot be used outside of a request cryptographically signed by the
Requestor; if so then this requirement can be relaxed, as in this case the Requestor; if so then this requirement can be relaxed, as in this case the
token cannot be re-used by another. However, unless both the Requestor and the token cannot be re-used by another. However, unless both the Requestor and the
Gateway are assured that this is the case, any authorization token MUST be Gateway are assured that this is the case, any authorization token MUST be
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expected to be held in opaque references inside the SDP body part of the expected to be held in opaque references inside the SDP body part of the
request. request.
The detailed operation of this mechanism is, by definition, outside the scope The detailed operation of this mechanism is, by definition, outside the scope
of an Internet Protocol, and so must be considered a private matter. However, of an Internet Protocol, and so must be considered a private matter. However,
one approach to indicating to the Requestor that such "second level" one approach to indicating to the Requestor that such "second level"
authentication or authorization is required by their Service Provider would be authentication or authorization is required by their Service Provider would be
to ask for this inside the textual description carried with a 401 response to ask for this inside the textual description carried with a 401 response
returned from the PINT Gateway. returned from the PINT Gateway.
-..-
5.4. Summary of Security Implications 5.4. Summary of Security Implications
>From the above discussion, PINT always carries data items that are sensitive, >From the above discussion, PINT always carries data items that are sensitive,
and there may be financial considerations as well as the more normal privacy and there may be financial considerations as well as the more normal privacy
concerns. As a result, the transactions MUST be protected from interception, concerns. As a result, the transactions MUST be protected from interception,
modification and replay in transit. modification and replay in transit.
PINT is based on SIP and SDP, and can use the security procedures outlined in PINT is based on SIP and SDP, and can use the security procedures outlined in
[1] (sections 13 and 15). However, in the case of PINT, the SIP recommendation [1] (sections 13 and 15). However, in the case of PINT, the SIP recommendation
that requests and responses MAY be protected is not enough. PINT messages MUST that requests and responses MAY be protected is not enough. PINT messages MUST
be protected, so PINT Implementations MUST support SIP Security (as described be protected, so PINT Implementations MUST support SIP Security (as described
in [1], sections 13 & 15), and be capable of handling such received messages. in [1], sections 13 & 15), and be capable of handling such received messages.
In some configurations, PINT Clients, Servers, and Gateways can be sure that In some configurations, PINT Clients, Servers, and Gateways can be sure that
they operate using the services of network level security [13], transport they operate using the services of network level security [13], transport
layer security [12], or physical security for all layer security [12], or physical security for all communications between them.
communications between them. In these cases messages MAY be exchanged In these cases messages MAY be exchanged without SIP security, since all
without SIP security, since all traffic is protected already. Clients traffic is protected already. Clients and servers SHOULD support manual
configuration to use such lower layer security facilities.
and servers SHOULD support manual configuration to use such lower
layer security facilities.
When using network layer security [13], the Security Policy Database When using network layer security [13], the Security Policy Database
MUST be configured to provide appropriate protection to PINT traffic. MUST be configured to provide appropriate protection to PINT traffic.
When using TLS, a port configured MUST NOT also When using TLS, a port configured MUST NOT also
be configured for non-TLS traffic. When TLS is used, basic authentication be configured for non-TLS traffic. When TLS is used, basic authentication
MUST be supported, and client-side certificates MAY be supported. MUST be supported, and client-side certificates MAY be supported.
Authentication of the Client making the request is required, however, so Authentication of the Client making the request is required, however, so
if this is not provided by the underlying mechanism used, then it MUST be if this is not provided by the underlying mechanism used, then it MUST be
included within the PINT messages using SIP authentication techniques. In included within the PINT messages using SIP authentication techniques. In
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With PINT, the registration is not for an individual but instead for a With PINT, the registration is not for an individual but instead for a
service that can be handled by a service provider. Thus, one can envisage a service that can be handled by a service provider. Thus, one can envisage a
registration by the PINT Server of the domain telcoA.com of its ability to registration by the PINT Server of the domain telcoA.com of its ability to
support the service R2C as "R2C@telcoA.com", sent to an intermediary server support the service R2C as "R2C@telcoA.com", sent to an intermediary server
that acts as registrar for the "broker.telcos.com" domain from that acts as registrar for the "broker.telcos.com" domain from
"R2C@pint.telcoA.com" as follows: "R2C@pint.telcoA.com" as follows:
REGISTER sip:registrar@broker.telcos.com SIP/2.0 REGISTER sip:registrar@broker.telcos.com SIP/2.0
To:sip:R2C@pint.telcoA.com To:sip:R2C@pint.telcoA.com
From:R2C@pint.telcoA.com From: sip:R2C@pint.telcoA.com
... ...
This is the standard SIP registration service. This is the standard SIP registration service.
However, what happens if there are a number of different Service Providers, However, what happens if there are a number of different Service Providers,
all of whom support the "R2C" service? Suppose there is a PINT system at all of whom support the "R2C" service? Suppose there is a PINT system at
domain "broker.com". PINT clients requesting a Request-to-Call service from domain "broker.com". PINT clients requesting a Request-to-Call service from
broker.com might be very willing to be redirected or proxied to any one of broker.com might be very willing to be redirected or proxied to any one of
the various service providers that had previously registered with the the various service providers that had previously registered with the
registrar. PINT servers might also be interested in providing service for registrar. PINT servers might also be interested in providing service for
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(iv) may choose to not allow registrations for the "general" service, (iv) may choose to not allow registrations for the "general" service,
rejecting all such REGISTER requests. rejecting all such REGISTER requests.
The algorithm by which such a choice is made will be The algorithm by which such a choice is made will be
implementation-dependent, and is outside the scope of PINT. Where a implementation-dependent, and is outside the scope of PINT. Where a
behaviour is to be defined by requesting users, then some sort of call behaviour is to be defined by requesting users, then some sort of call
processing language might be used to allow those clients, as a pre-service processing language might be used to allow those clients, as a pre-service
operation, to download the behaviour they expect to the server making such operation, to download the behaviour they expect to the server making such
decisions. This, however, is a topic for other protocols, not for PINT. decisions. This, however, is a topic for other protocols, not for PINT.
*-*-
6.4. Limitations on Available Information and Request Timing for SUBSCRIBE 6.4. Limitations on Available Information and Request Timing for SUBSCRIBE
A reference configuration for PINT is that service requests are sent, via a A reference configuration for PINT is that service requests are sent, via a
PINT Gateway, to an Executive System that fulfils the Service Control PINT Gateway, to an Executive System that fulfils the Service Control
Function (SCF) of an Intelligent Network (see [11]). The success or failure Function (SCF) of an Intelligent Network (see [11]). The success or failure
of the resulting service call may be information available to the SCF and so of the resulting service call may be information available to the SCF and so
may potentially be made available to the PINT Gateway. In terms of may potentially be made available to the PINT Gateway. In terms of
historical record of whether or not a service succeeded, a large SCF may be historical record of whether or not a service succeeded, a large SCF may be
dealing with a million call attempts per hour. Given that volume of service dealing with a million call attempts per hour. Given that volume of service
transactions, there are finite limits beyond which it cannot store service transactions, there are finite limits beyond which it cannot store service
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service is running. It may accept these requests and simply not even try to service is running. It may accept these requests and simply not even try to
query the Executive System until it has information that a service has query the Executive System until it has information that a service has
completed, merely returning the final status. Thus the PINT Requestor may be completed, merely returning the final status. Thus the PINT Requestor may be
in what it believes is a monitoring state, whilst the PINT Gateway has not in what it believes is a monitoring state, whilst the PINT Gateway has not
even informed the Executive System that a request has been made. This will even informed the Executive System that a request has been made. This will
increase the internal complexity of the PINT Gateway in that it will have a increase the internal complexity of the PINT Gateway in that it will have a
complex set of interlocking state machines, but does mean that status complex set of interlocking state machines, but does mean that status
registration and indication CAN be provided in conjunction with an I.N. registration and indication CAN be provided in conjunction with an I.N.
system. system.
6.5. Parameters needed for invoking traditional PSTN Services within PINT 6.5. Parameters needed for invoking traditional GSTN Services within PINT
This section describes how parameters needed to specify certain traditional This section describes how parameters needed to specify certain traditional
PSTN services can be carried within PINT requests. GSTN services can be carried within PINT requests.
6.5.1. Service Identifier 6.5.1. Service Identifier
When a Requesting User asks for a service to be performed, he or she will, When a Requesting User asks for a service to be performed, he or she will,
of course, have to specify in some way which service. This can be done of course, have to specify in some way which service. This can be done
in the URLs within the To: header and the Request-URI (see section 3.5.5.1). in the URLs within the To: header and the Request-URI (see section 3.5.5.1).
6.5.2. A and B parties 6.5.2. A and B parties
With the Request-to-Talk service, they will also need to specify the A and B With the Request-to-Call service, they will also need to specify the A and B
parties they want to be engaged in the resulting service call. The A party parties they want to be engaged in the resulting service call. The A party
could identify, for example, the Call Centre from which they want a call could identify, for example, the Call Centre from which they want a call
back, whilst the B party is their telephone number (i.e. who the Call Centre back, whilst the B party is their telephone number (i.e. who the Call Centre
agent is to call). agent is to call).
The Request-to-Fax and Request-to-Hear-Content services require the B party The Request-to-Fax and Request-to-Hear-Content services require the B party
to be specified (respectively the telephone number of the destination Fax to be specified (respectively the telephone number of the destination Fax
machine or the telephone to which spoken content is to be delivered), but machine or the telephone to which spoken content is to be delivered), but
the A party is a Telephone Network based resource (either a Fax or speech the A party is a Telephone Network based resource (either a Fax or speech
transcoder/sender), and is implicit; the Requesting User does not (and transcoder/sender), and is implicit; the Requesting User does not (and
cannot) specify it. cannot) specify it.
With the "Fax-Back" variant of the Request-to-Fax service, (i.e. where the With the "Fax-Back" variant of the Request-to-Fax service, (i.e. where the
content to be delivered resides on the GSTN) they will also have specify two content to be delivered resides on the GSTN) they will also have specify two
parties. As before, the B party is the telephone number of the fax machine parties. As before, the B party is the telephone number of the fax machine
to which they want a fax to be sent. However, within this variant the A to which they want a fax to be sent. However, within this variant the A
party identifies the "document context" for the PSTN-based document store party identifies the "document context" for the GSTN-based document store
from which a particular document is to be retrieved; the analogy here is to from which a particular document is to be retrieved; the analogy here is to
a PSTN user dialling a particular telephone number and then entering the a GSTN user dialling a particular telephone number and then entering the
document number to be returned using "touch tone" digits. The telephone document number to be returned using "touch tone" digits. The telephone
number they dial is that of the document store or A party, with the "touch number they dial is that of the document store or A party, with the "touch
tone" digits selecting the document within that store. tone" digits selecting the document within that store.
6.5.3. Other Service Parameters 6.5.3. Other Service Parameters
In terms of the extra parameters to the request, the services again differ. In terms of the extra parameters to the request, the services again differ.
The Request-to-Talk service needs only the A and B parties. Also it is The Request-to-Call service needs only the A and B parties. Also it is
convenient to assert that the resulting service call will carry voice, as convenient to assert that the resulting service call will carry voice, as
the Executive System within the destination GSTN may be able to check that the Executive System within the destination GSTN may be able to check that
assertion against the A and B party numbers specified and may treat the call assertion against the A and B party numbers specified and may treat the call
differently. differently.
With the Request-to-Fax and Request-to-Hear-Content services, the source With the Request-to-Fax and Request-to-Hear-Content services, the source
information to be transcoded is held on the Internet. That means either that information to be transcoded is held on the Internet. That means either that
this information is carried along with the request itself, or that a this information is carried along with the request itself, or that a
reference to the source of this information is given. In addition, it is reference to the source of this information is given. In addition, it is
convenient to assert that the service call will carry fax or voice, and, convenient to assert that the service call will carry fax or voice, and,
where possible, to specify the format for the source information. where possible, to specify the format for the source information.
The PSTN-based content or "Fax-Back" variant of the Request-to-Fax service The GSTN-based content or "Fax-Back" variant of the Request-to-Fax service
needs to specify the Document Store number and the Fax machine number to needs to specify the Document Store number and the Fax machine number to
which the information is to be delivered. It is convenient to assert that which the information is to be delivered. It is convenient to assert that
the call will carry Fax data, as the destination Executive System may be the call will carry Fax data, as the destination Executive System may be
able to check that assertion against the document store number and that of able to check that assertion against the document store number and that of
the destination Fax machine. the destination Fax machine.
In addition, the document number may also need to be sent. This parameter is In addition, the document number may also need to be sent. This parameter is
an opaque reference that is carried through the Internet but has an opaque reference that is carried through the Internet but has
significance only within the GSTN. The document store number and document significance only within the GSTN. The document store number and document
number together uniquely specify the actual content to be faxed. number together uniquely specify the actual content to be faxed.
6.5.4. Service Parameter Summary 6.5.4. Service Parameter Summary
The following table summarises the information needed in order to specify The following table summarises the information needed in order to specify
fully the intent of a PSTN service request. Note that it excludes any other fully the intent of a GSTN service request. Note that it excludes any other
parameters (such as authentication or authorisation tokens, or Expires: or parameters (such as authentication or authorisation tokens, or Expires: or
CallId: headers) that may be used in a request. CallId: headers) that may be used in a request.
Service ServiceID AParty BParty CallFmt Source SourceFmt Service ServiceID AParty BParty CallFmt Source SourceFmt
------- --------- ------ ------ ------- ------ ------- ------- --------- ------ ------ ------- ------ -------
R2C x x x voice - - R2C x x x voice - -
R2F x - x fax URI/IL ISF/ILSF R2F x - x fax URI/IL ISF/ILSF
R2FB x x x fax OR - R2FB x x x fax OR -
R2HC x - x voice URI/IL ISF/ILSF R2HC x - x voice URI/IL ISF/ILSF
In this table, "x" means that the parameter is required, whilst "-" means In this table, "x" means that the parameter is required, whilst "-" means
that the parameter is not required. that the parameter is not required.
The Services listed are Request to Talk (R2C), Request to Fax (R2F), the The Services listed are Request-to-Call (R2C), Request-to-Fax (R2F), the
PSTN-based content or "Fax-back" Variant of Request-to-Fax (R2FB), and GSTN-based content or "Fax-back" Variant of Request-to-Fax (R2FB), and
Request-to-Hear-Content (R2HC). Request-to-Hear-Content (R2HC).
The Call Format parameter values "voice" or "fax" indicate the kind of The Call Format parameter values "voice" or "fax" indicate the kind of
service call that results. service call that results.
The Source Indicator "URI/IL" implies either that the data is either an The Source Indicator "URI/IL" implies either that the data is either an
Internet source reference (a Universal Resource Identifier, or URI) or is Internet source reference (a Universal Resource Identifier, or URI) or is
carried "in-line" with the message. The Source indicator "OR" means that carried "in-line" with the message. The Source indicator "OR" means that
the value passed is an Opaque Reference that should be carried along the value passed is an Opaque Reference that should be carried along
skipping to change at page 48, line 25 skipping to change at page 49, line 25
specified either in terms of the URI or that it is carried "in-line". Note specified either in terms of the URI or that it is carried "in-line". Note
that, for some data, the format either can be detected by inspection or, if that, for some data, the format either can be detected by inspection or, if
all else fails, can be assumed from the URI (for example, by assuming that all else fails, can be assumed from the URI (for example, by assuming that
the file extension part of a URL indicates the data type). For an opaque the file extension part of a URL indicates the data type). For an opaque
reference, the Source Format is not available on the Internet, and so is not reference, the Source Format is not available on the Internet, and so is not
given. given.
6.6. Parameter Mapping to PINT Extensions 6.6. Parameter Mapping to PINT Extensions
This section describes the way in which the parameters needed to specify a This section describes the way in which the parameters needed to specify a
PSTN service request fully might be carried within a "PINT extended" message. GSTN service request fully might be carried within a "PINT extended" message.
There are other choices, and these are not precluded. However, in order to There are other choices, and these are not precluded. However, in order to
ensure that the Requesting User receives the service that they expect, it is ensure that the Requesting User receives the service that they expect, it is
necessary to have some shared understanding of the parameters passed and the necessary to have some shared understanding of the parameters passed and the
behaviour expected of the PINT Server and its attendant Executive System. behaviour expected of the PINT Server and its attendant Executive System.
The Service Identifier can be sent as the userinfo element of the The Service Identifier can be sent as the userinfo element of the
Request-URI. Thus, the first line of a PINT Invitation would be of the form: Request-URI. Thus, the first line of a PINT Invitation would be of the form:
INVITE <serviceID>@<pint-server>.<domain> SIP/2.0 INVITE <serviceID>@<pint-server>.<domain> SIP/2.0
The A Party for the Request-to-Talk and "Fax-back" variant of Request-to-Fax The A Party for the Request-to-Call and "Fax-back" variant of Request-to-Fax
service can be held in the "To:" header field. In this case the "To:" header service can be held in the "To:" header field. In this case the "To:" header
value will be different from the Request-URI. In the services where the A value will be different from the Request-URI. In the services where the A
party is not specified, the "To:" field is free to repeat the value held in party is not specified, the "To:" field is free to repeat the value held in
the Request-URI. This is the case for Request-to-Fax and the Request-URI. This is the case for Request-to-Fax and
Request-to-Hear-Content services. Request-to-Hear-Content services.
The B party is needed in all these milestone services, and can be held in The B party is needed in all these milestone services, and can be held in
the enclosed SDP sub-part, as the value of the "c=" field. the enclosed SDP sub-part, as the value of the "c=" field.
The call format parameter can be held as part of the "m=" field value. It The call format parameter can be held as part of the "m=" field value. It
maps to the "transport protocol" element as described in section 3.4.2 of maps to the "transport protocol" element as described in section 3.4.2 of
this document. this document.
..--
The source format specifier is held in the "m=", as a type and optional The source format specifier is held in the "m=", as a type and either "-"
sub-type. The latter is normally required for all services except or sub-type. The latter is normally required for all services except
Request-to-Talk. As shown earlier, the source format and source are not Request-to-Call or "Faxback", where the "-" form may be used. As shown
always required when generating requests for services. However, the inclusion earlier, the source format and source are not always required when
in all requests of a source format specifier can make parsing the request generating requests for services. However, the inclusion in all requests
simpler and allows for other services to be specified in the future, and so of a source format specifier can make parsing the request simpler and
values are always given. The source format parameter is covered in section allows for other services to be specified in the future, and so values
3.4.2 as the "media type" element. are always given. The source format parameter is covered in section 3.4.2
as the "media type" element.
The source itself is identified by an "a=fmtp:" field value, where needed. The source itself is identified by an "a=fmtp:" field value, where needed.
With the exception of the Request-to-Talk service, all invitations will With the exception of the Request-to-Call service, all invitations will
normally include such a field. From the perspective of the SDP extensions, normally include such a field. From the perspective of the SDP extensions,
it can be considered as qualifying the media sub-type, as if to say, it can be considered as qualifying the media sub-type, as if to say,
for example, "when I say jpeg, what I mean is the following". for example, "when I say jpeg, what I mean is the following".
In summary, the parameters needed by the different services are carried in In summary, the parameters needed by the different services are carried in
fields as shown in the following table: fields as shown in the following table:
Service Svc Param PINT/SIP or SDP field used Example value Service Svc Param PINT/SIP or SDP field used Example value
------- --------- -------------------------- ------------- ------- --------- -------------------------- -------------
skipping to change at page 50, line 25 skipping to change at page 51, line 25
preceding m= field> a=fmtp:html <uri-ref> preceding m= field> a=fmtp:html <uri-ref>
7. Open Issues and Draft State 7. Open Issues and Draft State
7.1. Open Issues 7.1. Open Issues
Thre are no current technical open issues. Thre are no current technical open issues.
7.2. Draft State 7.2. Draft State
Please note that changes are cumulative. This draft reflects all changes resulting from the WG "last call" phase.
Changes from version 00:
* Removed References to Q763 parameters.
It is difficult to see how these prameters could be passed to an Intelligent
Network System, and in many potential configurations this information would
not be accepted, as it did not come from a "trusted" source.
* Removed references to ITU and other standardisation efforts.
A PINT standards-track RFC cannot really refer to standards that are in
progress. The set of IETF references are to documents that are on the
Standards Track. Standardisation efforts in other organisations are subject
to change and so these references are not appropriate.
Changes from version 01 to previous interim version:
* Corrected a few typos, orphaned internal references, and some of the
examples.
* Made a few corrections and added some comments on changes to be expected
in the next draft. These were highlighted by **** before the affected
paragraphs.
* Removed references to the Telephony URL draft that has expired. It seems
likely that the SIP draft will reach RFC status first.
Changes from interim version to profile version 03:
* removed previous change marks
* New changes are indicated by *-*- in the text above the change
* Corrected a few more typos, and re-visited the examples
(thanks to Francois for the MIME comments!)
* removed refs to out of date Internet Conference Architecture draft
from "Introduction"
* Corrected a few more typos, and re-visited the examples
* added initial summary list for new PINT features
in "PINT Protocol Architecture"
* added a comment on the MIME version implied by PINT 1.0
in "PINT Protocol Architecture"
* added sub-section number for SDP description in "PINT Protocol
Architecture"
* added sub-section number for SIP description in "PINT Protocol
Architecture"
* removed reference to Security mechanisms in "SIP Operation in PINT"
* added strictures as MUST and split into separate paras for clarity in
"REQUIRED and OPTIONAL elements for PINT compliance"
* added comment that PINT features may be useful for SIP/SDP in "REQUIRED
and OPTIONAL elements for PINT compliance"
* changed E.164 number -> N.P.A., and added local dialling plan number
in " Network Type "TN" and Address Type "RFC2543"
* added an introductory section on data object support in PINT & rewrote
section in "Support for Data Objects within PINT"
* added section on opaque references in "Support for Data Objects within
PINT"
* changed section number and reworked text in "Session Description
support for included Data Objects"
* removed ref to former (non-tagged) method of checking resolution type
in "Session Description support for included Data Objects"
* moved last part of section to the SIP description, leaving a ref. in
"Session Description support for included Data Objects"
* highlighted that attributes may appear as PINT URL parameters in SIP in
"Attribute Tags to pass information into the Telephone Network"
* moved para from end of "phone-context attribute" to main body of
"Attribute Tags to pass information into the Telephone Network"
* added sub-section added (by request) on "Presentation Restriction
attribute"
* Re-introduced sub-section on "CalledPartyAddress attributes parameters"
(Q763 parameters), also by request
* added comment on the general form of Q763 attributes to the original
content of this section
* added a comment that all PINT extensions can be covered by Strictures
to "The "strict" attribute"
* moved some orphaned text from "Session Description support for included
Data Objects" into "Multi-part MIME"
* removed sub-section on " PINT URLS within To: headers" and comments on
"1-800-FLOWERS" style telephony URLs
* removed references to wildcards in REGISTER messages within " REGISTER
requests within PINT"
* replaced example 4.8 with new examples 4.8 - 4.12
* added section on "Limitations on Available Information and Request
Timing for SUBSCRIBE"
* added a few references that were missing
* added "Collected ABNF" Appendix.
Changes from profile version 3 to verion 4:
* New changes are indicated by a -*-* mark on the line before the change
* added a Security Considerations Section
* really added the comment on PINT/SIP implying MIME 1.0 this time!
* added ABNF definition for the use of PINT attributes as URL parameters
* added ABNF definition of tsp URL parameter
* added a statement that there are no current technical open issues
* corrected boilerplate
* added reference to SIP RFC number.
Changes from profile version 4 to this version (indicated by -.-.)
* In section 4.1, changed wording to emphasize that a "+1" number falls
within the N.A.N.P. region.
* Changed Ordering of Authors.
* Changed incorrect reference to SIP in 3.4.4 - should be SDP
* CHANGED! "strict:" SDP attribute to "require:" throughout
* Corrected typos in 3.1 and 4.6 and 3.4.3.1, clarified text in 3.4.1
* Changed title (repl. "profile" with more appropriate terms throughout)
* CHANGED! SHOULD to MUST in 5.2 and also in 5.3
* Added section on privacy implications of identifying the associated
requst within SUBSCRIBE (section 5.1.4)
* Added IANA Considerations Appendix
* CHANGED! specification of Port value to "1" for PINT in 3.4.2 and ABNF
* CHANGED! spec of "defaulted" media sub-type; uses "-" rather than empty
ABNF CHANGES:
* throughout, changed "|" to "/" as per RFC2234 (oops).
* changed use of "<" and ">" throughout. these now imply a definition
in another document (except for the initial connection-field
definition that is merely copied to the PINT ABNF for completeness).
* re-ordered rules to have refinements follow from dependent rules
* added comments to show which rule names are redefinitions of SDP/SIP
names. Where the redefinitions are not pure supersets, comment is
preceded with "NOTE".
* removed stray "media " from the pint-fmtp definition.
* added space separators within PINT variant of fmtp attribute to
deleniate the resolution items, if there's more than one.
* changed definition of PINT variant of fmtp attribute to allow existing
SDP attributes to be appended. Note that this allows zero or more sets
of one or more attributes, with a semi-colon preceeding each set, and
with spaces separating each attribute from its neighbours.
* comma-separated values for require-header and strict-attribute.
* added terminals for each of the tags used in attributes/parameters.
* corrected mistaken ABNF definition of strict/require attribute
- it should include just the field tags, not complete attributes!
* changed the tag value of the strict attribute to "require" for
consistency with the equivalent(ish) require-header, as per request.
Note that they now share the same tag value ("require:").
* added strict-attribute to the list of PINT/SDP attributes (duh!)
* added some extra rule names for common elements (for q763xx)
* added the fmtp explicit source type tags (uri, spr, and opr) to the
list of items that may be specified in a strict-attribute. For PINT,
the expected behaviour on the part of a recipient (as mentioned in the
body text) is that it should fail an Invitation including one of these
constructs that it doesn't support. However, including these in a
strict-attribute allows them to be used in the wider SIP/SDP context
(e.g. as part of an OPTIONS message exchange).
Changes from "protocol" version 00 to this version (indicated by -..-)
* Security summary section 5.4 clarified and improved
8. References 8. References
[1] M. Handley, E. Schooler, H. Schulzrinne, & J. Rosenberg, [1] M. Handley, E. Schooler, H. Schulzrinne, & J. Rosenberg,
"SIP: Session Initiation Protocol", RFC2543, "SIP: Session Initiation Protocol", RFC2543,
Internet Engineering Task Force, March 1999. Internet Engineering Task Force, March 1999.
[2] M. Handley & V. Jacobsen, [2] M. Handley & V. Jacobsen,
"SDP: Session Description Protocol", RFC2327, "SDP: Session Description Protocol", RFC2327,
Internet Engineering Task Force, April 1998. Internet Engineering Task Force, April 1998.
[3] N. Freed & N. Borenstein, [3] N. Freed & N. Borenstein,
"Multipurpose Internet Mail Extensions (MIME) "Multipurpose Internet Mail Extensions (MIME)
Part One: Format of Internet Message Bodies", Part One: Format of Internet Message Bodies",
RFC2045, November 1996. RFC2045, November 1996.
[4] N. Freed & N. Borenstein, [4] N. Freed & N. Borenstein,
"Multipurpose Internet Mail Extensions (MIME) "Multipurpose Internet Mail Extensions (MIME)
Part Two: Media Types", Part Two: Media Types",
skipping to change at page 53, line 54 skipping to change at page 52, line 28
"Internet X.509 Public Key Infrastructure Certificate and CRL Profile", "Internet X.509 Public Key Infrastructure Certificate and CRL Profile",
RFC2459, Internet Engineering Task Force, January 1999. RFC2459, Internet Engineering Task Force, January 1999.
[15] D. Crocker & P. Overall, [15] D. Crocker & P. Overall,
"Augmented BNF for Syntax Specifications: ABNF", RFC2234, "Augmented BNF for Syntax Specifications: ABNF", RFC2234,
Internet Engineering Task Force, November 1997. Internet Engineering Task Force, November 1997.
[16] D. Mills, "Network Time Protocol (version 3) specification and [16] D. Mills, "Network Time Protocol (version 3) specification and
implementation", RFC1305, Internet Engineering Task Force, March 1992. implementation", RFC1305, Internet Engineering Task Force, March 1992.
[17] D. Eastlake, S. Crocker & J.Schiller, [17] D. Eastlake, S. Crocker & J.Schiller,
"Randomness Recommendations for Security", Informational RFC 1305, "Randomness Recommendations for Security", Informational RFC 1305,
Internet Engineering Task Force, March 1992. Internet Engineering Task Force, March 1992.
[18] P. Mockapetris,
"Domain Names - Implementation and Specification" RFC 1035,
Inernet Engineering Task Force November 1987.
9. Acknowledgements 9. Acknowledgements
The authors wish to thank the members of the PINT working group for comments
that were helpful to the preparation of this specification. Ian Elz's The authors wish to thank the members of the PINT working group for
comments were extremely useful to our understanding of internal PSTN comments that were helpful to the preparation of this specification.
operations. The SUBSCRIBE and NOTIFY requests were first suggested by Ian Elz's comments were extremely useful to our understanding of internal
Henning Schulzrinne and Jonathan Rosenberg. PSTN operations. The SUBSCRIBE and NOTIFY requests were first suggested
by Henning Schulzrinne and Jonathan Rosenberg. Finally, thanks to Bernie
Hoeneisen for his close proofreading.
Appendix A: Collected ABNF for PINT Extensions Appendix A: Collected ABNF for PINT Extensions
;; --(ABNF is specified in RFC 2234 [15]) ;; --(ABNF is specified in RFC 2234 [15])
;; --Variations on SDP definitions ;; --Variations on SDP definitions
connection-field = ["c=" nettype space addrtype space connection-field = ["c=" nettype space addrtype space
connection-address CRLF] connection-address CRLF]
; -- this is the original definition from SDP, included for completeness ; -- this is the original definition from SDP, included for completeness
; -- the following are PINT interpretations and modifications ; -- the following are PINT interpretations and modifications
skipping to change at page 55, line 17 skipping to change at page 54, line 17
; -- 0 retains usual sdp meaning of "temporarily no media" ; -- 0 retains usual sdp meaning of "temporarily no media"
; -- (i.e. "line is on hold") ; -- (i.e. "line is on hold")
; -- (1 means there is media) ; -- (1 means there is media)
proto = (INProto/TNProto) proto = (INProto/TNProto)
; -- redefined as a superset of the original SDP definition ; -- redefined as a superset of the original SDP definition
INProto = 1* (<alpha-numeric>) INProto = 1* (<alpha-numeric>)
; -- this is the "classic" SDP protocol, defined if nettype == "IN" ; -- this is the "classic" SDP protocol, defined if nettype == "IN"
; -- alpha-numeric is as defined in SDP ; -- alpha-numeric is as defined in SDP
..--
TNProto = ("phone"/"fax"/"pager") TNProto = ("voice"/"fax"/"pager")
; -- this is the PINT protocol, defined if nettype == "TN" ; -- this is the PINT protocol, defined if nettype == "TN"
fmt = (<subtype> / "-") fmt = (<subtype> / "-")
; -- NOTE redefined as a subset of the original SDP definition ; -- NOTE redefined as a subset of the original SDP definition
; -- subtype as defined in RFC2046, or "-". MUST be a subtype of type held ; -- subtype as defined in RFC2046, or "-". MUST be a subtype of type held
; -- in associated media sub-field or the special value "-". ; -- in associated media sub-field or the special value "-".
-.-.
attribute-fields = *("a=" attribute-list <CRLF>) attribute-fields = *("a=" attribute-list <CRLF>)
; -- redefined as a superset of the definition given in SDP ; -- redefined as a superset of the definition given in SDP
; -- CRLF is as defined in SDP ; -- CRLF is as defined in SDP
attribute-list = 1(PINT-attribute / <attribute>) attribute-list = 1(PINT-attribute / <attribute>)
; -- attribute is as defined in SDP ; -- attribute is as defined in SDP
-.-.
PINT-attribute = (clir-attribute / q763-nature-attribute / PINT-attribute = (clir-attribute / q763-nature-attribute /
q763plan-attribute / q763-INN-attribute / q763plan-attribute / q763-INN-attribute /
phone-context-attribute / phone-context-attribute / tsp-attribute /
pint-fmtp-attribute / strict-attribute) pint-fmtp-attribute / strict-attribute)
-.-.
clir-attribute = clir-tag ":" ("true" / "false") clir-attribute = clir-tag ":" ("true" / "false")
-.-.
clir-tag = "clir" clir-tag = "clir"
-.-.
q763-nature-attribute = Q763-nature-tag ":" q763-natures q763-nature-attribute = Q763-nature-tag ":" q763-natures
-.-.
q763-nature-tag = "Q763-nature" q763-nature-tag = "Q763-nature"
-.-.
q763-natures = ("1" / "2" / "3" / "4") q763-natures = ("1" / "2" / "3" / "4")
-.-.
q763-plan-attribute = Q763-plan-tag ":" q763-plans q763-plan-attribute = Q763-plan-tag ":" q763-plans
-.-.
q763-plan-tag = "Q763-plan" q763-plan-tag = "Q763-plan"
-.-.
q763-plans = ("1" / "2" / "3" / "4" / "5" / "6" / "7") q763-plans = ("1" / "2" / "3" / "4" / "5" / "6" / "7")
; -- of these, the meanings of 1, 3, and 4 are defined in the text ; -- of these, the meanings of 1, 3, and 4 are defined in the text
-.-.
q763-INN-attribute = Q763-INN-tag ":" q763-INNs q763-INN-attribute = Q763-INN-tag ":" q763-INNs
-.-.
q763-INN-tag = "Q763-INN" q763-INN-tag = "Q763-INN"
-.-.
q763-INNs = ("0" / "1") q763-INNs = ("0" / "1")
-.-.
phone-context-attribute = phone-context-tag ":" phone-context-ident phone-context-attribute = phone-context-tag ":" phone-context-ident
-.-.
phone-context-tag = "phone-context" phone-context-tag = "phone-context"
phone-context-ident = network-prefix / private-prefix phone-context-ident = network-prefix / private-prefix
network-prefix = intl-network-prefix / local-network-prefix network-prefix = intl-network-prefix / local-network-prefix
intl-network-prefix = "+" 1*<DIGIT> intl-network-prefix = "+" 1*<DIGIT>
local-network-prefix = 1*<DIGIT> local-network-prefix = 1*<DIGIT>
private-prefix = 1*excldigandplus 0*<uric> private-prefix = 1*excldigandplus 0*<uric>
excldigandplus = (0x21-0x2d,0x2f,0x40-0x7d)) excldigandplus = (0x21-0x2d,0x2f,0x40-0x7d))
..--
tsp-attribute = tsp-tag "=" provider-domainname
tsp-tag = "tsp"
provider-domainname = <domain>
; -- domain is defined in RFC1035
-.-.
; -- NOTE the following is redefined relative to the normal use in SDP ; -- NOTE the following is redefined relative to the normal use in SDP
pint-fmtp-attribute = "fmtp:" <subtype> <space> resolution pint-fmtp-attribute = "fmtp:" <subtype> <space> resolution
*(<space> resolution) *(<space> resolution)
(<space> ";" 1(<attribute>) *(<space> <attribute>)) (<space> ";" 1(<attribute>) *(<space> <attribute>))
; -- subtype as defined in RFC2046. ; -- subtype as defined in RFC2046.
; -- NOTE that this value MUST match a fmt on the ultimately preceeding ; -- NOTE that this value MUST match a fmt on the ultimately preceeding
; -- media-field ; -- media-field
; -- attribute is as defined in SDP ; -- attribute is as defined in SDP
-.-.
resolution = (uri-ref / opaque-ref / sub-part-ref) resolution = (uri-ref / opaque-ref / sub-part-ref)
-.-.
uri-ref = uri-tag ":" <URI-Reference> uri-ref = uri-tag ":" <URI-Reference>
; -- URI-Reference defined in RFC2396 ; -- URI-Reference defined in RFC2396
-.-.
uritag = "uri" uritag = "uri"
-.-.
opaque-ref = opr-tag ":" 0*<uric> opaque-ref = opr-tag ":" 0*<uric>
-.-.
opr-tag = "opr" opr-tag = "opr"
-.-.
sub-part-ref = spr-tag ":" <Content-ID> sub-part-ref = spr-tag ":" <Content-ID>
; -- Content-ID is as defined in RFC2046 and RFC822 ; -- Content-ID is as defined in RFC2046 and RFC822
-.-.
spr-tag = "spr" spr-tag = "spr"
-.-.
strict-attribute = "require:" att-tag-list strict-attribute = "require:" att-tag-list
-.-.
att-tag-list = 1(PINT-att-tag-list / <att-field> / att-tag-list = 1(PINT-att-tag-list / <att-field> /
pint-fmtp-tag-list) pint-fmtp-tag-list)
*("," *(","
(PINT-att-tag-list / <att-field> / (PINT-att-tag-list / <att-field> /
pint-fmtp-tag-list) pint-fmtp-tag-list)
) )
; -- att-field as defined in SDP ; -- att-field as defined in SDP
-.-.
PINT-att-tag-list = (phone-context-tag / clir-tag / PINT-att-tag-list = (phone-context-tag / clir-tag /
q763-nature-tag / q763-plan-tag / q763-nature-tag / q763-plan-tag /
q763-INN-tag) q763-INN-tag)
-.-.
pint-fmtp-tag-list = (uri-tag / opr-tag / spr-tag) pint-fmtp-tag-list = (uri-tag / opr-tag / spr-tag)
;; --Variations on SIP definitions ;; --Variations on SIP definitions
-.-.
clir-parameter = clir-tag "=" ("true" / "false") clir-parameter = clir-tag "=" ("true" / "false")
-.-.
q763-nature-parameter = Q763-nature-tag "=" Q763-natures q763-nature-parameter = Q763-nature-tag "=" Q763-natures
-.-.
q763plan-parameter = Q763-plan-tag "=" q763plans q763plan-parameter = Q763-plan-tag "=" q763plans
-.-.
q763-INN-parameter = Q763-INN-tag "=" q763-INNs q763-INN-parameter = Q763-INN-tag "=" q763-INNs
-.-. tsp-parameter = tsp-tag "=" provider-domainname
tsp-parameter = tsp-tag "=" <hostname>
; -- hostname is as defined in SIP
-.-.
tsp-tag = "tsp"
-.-.
phone-context-parameter = phone-context-tag "=" phone-context-ident phone-context-parameter = phone-context-tag "=" phone-context-ident
SIP-param = ( <transport-param> / <user-param> / <method-param> / SIP-param = ( <transport-param> / <user-param> / <method-param> /
<ttl-param> / <maddr-param> / <other-param> ) <ttl-param> / <maddr-param> / <other-param> )
; -- the values in this list are all as defined in SIP ; -- the values in this list are all as defined in SIP
PINT-param = ( clir-parameter / q763-nature-parameter / PINT-param = ( clir-parameter / q763-nature-parameter /
q763plan-parameter / q763-INN-parameter/ q763plan-parameter / q763-INN-parameter/
tsp-parameter / phone-context-parameter ) tsp-parameter / phone-context-parameter )
URL-parameter = (SIP-param / PINT-param) URL-parameter = (SIP-param / PINT-param)
; -- redefined SIP's URL-parameter to include ones defined in PINT ; -- redefined SIP's URL-parameter to include ones defined in PINT
-.-.
Require-header = "require:" 1(required-extensions) Require-header = "require:" 1(required-extensions)
*("," required-extensions) *("," required-extensions)
; -- NOTE this is redefined as a subset of the SIP definition ; -- NOTE this is redefined as a subset of the SIP definition
; -- (from RFC2543/section 6.30) ; -- (from RFC2543/section 6.30)
-.-.
required-extensions = ("org.ietf.sip.subscribe" / required-extensions = ("org.ietf.sip.subscribe" /
"org.ietf.sdp.require") "org.ietf.sdp.require")
Appendix B: IANA Considerations Appendix B: IANA Considerations
There are three kinds of identifier used in PINT extensions that SHOULD There are three kinds of identifier used in PINT extensions that SHOULD
be registered with IANA, if a new value is specified. These are: be registered with IANA, if a new value is specified. These are:
* Media Format sub-types, as described in section 3.4.2 of this document. * Media Format sub-types, as described in section 3.4.2 of this document.
* Private Attributes as mentioned in section 3.4.3 * Private Attributes as mentioned in section 3.4.3
* Private Phone Context values, as described in section 3.4.3.1. * Private Phone Context values, as described in section 3.4.3.1.
 End of changes. 253 change blocks. 
453 lines changed or deleted 303 lines changed or added

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