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Versions: (draft-berger-ccamp-gmpls-alarm-spec)
00 01 02 03 04 05 06 RFC 4783
Internet Draft Lou Berger - Editor (LabN)
Updates: 3473
Category: Standards Track
Expiration Date: February 2007
August 2006
GMPLS - Communication of Alarm Information
draft-ietf-ccamp-gmpls-alarm-spec-04.txt
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Abstract
This document describes an extension to Generalized MPLS (Multi-
Protocol Label Switching) signaling to support communication of alarm
information. GMPLS signaling already supports the control of alarm
reporting, but not the communication of alarm information. This
document presents both a functional description and GMPLS-RSVP
specifics of such an extension. This document also proposes
modification of the RSVP ERROR_SPEC object.
This document updates RFC 3473 "Generalized Multi-Protocol Label
Switching (GMPLS) Signaling Resource ReserVation Protocol-Traffic
Engineering (RSVP-TE) Extensions" through the addition of new,
optional protocol elements. It does not change, and is fully backward
compatible with the procedures specified in RFC 3473.
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Contents
1 Introduction .............................................. 3
1.1 Background ................................................ 3
2 Alarm Information Communication ........................... 4
3 GMPLS-RSVP Details ........................................ 5
3.1 ALARM_SPEC Objects ........................................ 5
3.1.1 IF_ID ALARM_SPEC (and ERROR_SPEC) TLVs .................... 6
3.1.2 Procedures ................................................ 9
3.1.3 Error Codes and Values .................................... 10
3.1.4 Backwards Compatibility ................................... 11
3.2 Controlling Alarm Communication ........................... 11
3.2.1 Updated Admin Status Object ............................... 11
3.2.2 Procedures ................................................ 11
3.3 Message Formats ........................................... 12
3.4 Relationship to GMPLS UNI ................................. 13
3.5 Relationship to GMPLS E-NNI .............................. 14
4 Security Considerations ................................... 14
5 IANA Considerations ....................................... 15
6 References ................................................ 16
6.1 Normative References ...................................... 16
6.2 Informative References .................................... 16
7 Contributors .............................................. 17
8 Contact Address ........................................... 17
9 Full Copyright Statement .................................. 18
10 Intellectual Property ..................................... 18
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1. Introduction
GMPLS Signaling provides mechanisms that can be used to control the
reporting of alarms associated with an LSP. This support is provided
via Administrative Status Information [RFC3471] and the Admin_Status
object [RFC3473]. These mechanisms only control if alarm reporting
is inhibited. No provision is made for communication of alarm
information within GMPLS.
The extension described in this document defines how the alarm
information associated with a GMPLS label-switched path (LSP) may be
communicated along the path of the LSP. Communication both upstream
and downstream is supported. The value in communicating such alarm
information is that this information is then available at every node
along the LSP for display and diagnostic purposes. Alarm information
may also be useful in certain traffic protection scenarios, but such
uses are out of scope of this document. Alarm communication is
supported via a new object, new error/alarm information TLVs, and a
new Administrative Status Information bit.
The communication of alarms, as described in this document, is
controllable on a per LSP basis. Such communication may be useful
within network configurations where not all nodes support
communication to a user for reporting of alarms and/or communication
is needed to support specific applications. The support of this
functionality is optional.
The communication of alarms within GMPLS does not imply any
modification in behavior of processing of alarms, or for the
communication of alarms outside of GMPLS. Additionally, the
extension described in this document is not intended to replace any
(existing) data plane fault propagation techniques.
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119].
1.1. Background
Problems with data plane state can often be detected by associated
data plane hardware components. Such data plane problems are
typically filtered based on elapsed time and local policy. Problems
that pass the filtering process are normally raised as alarms. These
alarms are available for display to operators. They also may be
collected centrally through means that are out of the scope of this
document.
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Not all data plane problems cause the LSP to be immediately torn
down. Further, there may be a desire, particularly in optical
transport networks, to retain an LSP and communicate relevant alarm
information even when the data plane state has failed completely.
Although error information can be reported using PathErr, ResvErr and
Notify messages, these messages typically indicate a problem in
signaling state and can only report one problem at at a time. This
makes it hard to correlate all of the problems that may be associated
with a single LSP and to allow an operator examining the status of an
LSP to view a full list of current problems. This situation is
exacerbated by the absence of any way to communicate that a problem
has been resolved and a corresponding alarm cleared.
The extensions defined in this document allow an operator or a
software component to obtain a full list of current alarms associated
with all of the resources used to support an LSP. The extensions
also ensure that this list is kept up-to-date and synchronized with
the real alarm status in the network. Finally, the extensions make
the list available at every node traversed by an LSP.
2. Alarm Information Communication
A new object is introduced to carry alarm information details. The
details of alarm information are much like the error information
carried in the existing ERROR_SPEC objects. For this reason the
communication of alarm information uses a format that is based on the
communication of error information.
The new object introduced to carry alarm information details is
called an ALARM_SPEC object. This object has the same format as the
ERROR_SPEC object, but uses a new C-Num to avoid the semantics of
error processing. Also, additional TLVs are defined for the IF_ID
ALARM_SPEC objects to support the communication of information
related to a specific alarm. These TLVs may also be useful when
included in ERROR_SPEC objects, e.g., when the ERROR_SPEC object is
carried within a Notify message.
While the details of alarm information are like the details of
existing error communication, the semantics of processing differ.
Alarm information will typically relate to changes in data plane
state, without changes in control state. Alarm information will
always be associated with in-place LSPs. Such information will also
typically be most useful to operators and applications other than
control plane protocol processing. Finally, while error information
is communicated within PathErr, ResvErr and Notify messages
[RFC3473], alarm information will be carried within Path and Resv
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messages.
Path messages are used to carry alarm information to downstream nodes
and Resv messages are used to carry alarm information to upstream
nodes. The intent of sending alarm information both upstream and
downstream is to provide the same visibility to alarm information at
any point along an LSP. The communication of multiple alarms
associated with an LSP is supported. In this case, multiple
ALARM_SPEC objects will be carried in the Path or Resv messages.
The addition of alarm information to Path and Resv messages is
controlled via a new Administrative Status Information bit.
Administrative Status Information is carried in the Admin_Status
object.
3. GMPLS-RSVP Details
This section provides the GMPLS-RSVP [RFC3473] specification for
communication of alarm information. The communication of alarm
information is optional. This section applies to nodes that support
communication of alarm information.
3.1. ALARM_SPEC Objects
The ALARM_SPEC objects use the same format as the ERROR_SPEC object,
but with class number of TBA (to be assigned by IANA in the form
11bbbbbb, per Section 3.1.4).
o Class = TBA, C-Type = 1
Reserved. (C-Type value defined for ERROR_SPEC, but is not defined
for use with ALARM_SPEC.)
o Class = TBA, C-Type = 2
Reserved. (C-Type value defined for ERROR_SPEC, but is not defined
for use with ALARM_SPEC.)
o IPv4 IF_ID ALARM_SPEC object: Class = TBA, C-Type = 3
Definition same as IPv4 IF_ID ERROR_SPEC [RFC3473].
o IPv6 IF_ID ALARM_SPEC object: Class = TBA, C-Type = 4
Definition same as IPv6 IF_ID ERROR_SPEC [RFC3473].
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3.1.1. IF_ID ALARM_SPEC (and ERROR_SPEC) TLVs
The following new TLVs are defined for use with the IPv4 and IPv6
IF_ID ALARM_SPEC objects. They may also be used with the IPv4 and
IPv6 IF_ID ERROR_SPEC objects. See [RFC3471] section 9.1.1 for the
original definition of these values. Note the length provided below
is for the total TLV. All TLVs defined in this section are optional.
The defined TLVs MUST follow any interface identifying TLVs. No
rules apply to the relative ordering of the TLVs defined in this
section.
[Note: Type values are TBA (to be assigned) by IANA]
Type Length Description
----------------------------------
512 8 REFERENCE_COUNT
513 8 SEVERITY
514 8 GLOBAL_TIMESTAMP
515 8 LOCAL_TIMESTAMP
516 variable ERROR_STRING
The Reference Count TLV has the following format:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reference Count |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Reference Count: 32 bits
The number of times this alarm has been repeated as determined
by the reporting node. This field MUST NOT be set to zero.
Only one Reference Count TLV may be included in an object.
The Severity TLV has the following format:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved |Impact | Severity |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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Reserved: 24 bits
This field is reserved. It MUST be set to zero on generation,
MUST be ignored on receipt and MUST be forwarded unchanged and
unexamined by transit nodes.
Impact: 4 bits
Indicates the impact of the alarm indicated in the TLV. See
[M.20] for a general discussion on classification of failures.
The following values are defined:
Value Definition
----- ---------------------
0 Unspecified impact
1 Non-Service Affecting (Data traffic not interrupted)
2 Service Affecting (Data traffic is interrupted)
Severity: 8 bits
Indicates the impact of the alarm indicated in the TLV. See
[RFC3877] and [M.3100] for more information on severity. The
following values are defined:
Value Definition
----- ----------
0 Cleared
1 Indeterminate
2 Critical
3 Major
4 Minor
5 Warning
Only one Severity TLV may be included in an object.
The Global Timestamp TLV has the following format:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Global Timestamp |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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Global Timestamp: 32 bits
The number of seconds since 0000 UT on 1 January 1970,
according to the clock on the node that originates this TLV.
Only one Global Timestamp TLV may be included in an object.
The Local Timestamp TLV has the following format:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Local Timestamp |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Local Timestamp: 32 bits
Number of seconds reported by the local system clock at the
time the associated alarm was detected on the node that
originates this TLV. This number is expected to be meaningful
in the context of the originating node. For example, it may
indicate the number of seconds since the node rebooted or may
be a local representation of an unsynchronized real-time clock.
Only one Local Timestamp TLV may be included in an object.
The Error String TLV has the following format:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
// Error String (NULL padded display string) //
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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Error String: 32 bits minimum (variable)
A string of characters in US-ASCII, representing the type of
error/alarm. This string is padded to the next largest 4 byte
boundary using null characters. Null padding is not required
when the string is 32-bit aligned. The contents of error
string are implementation dependent. See the condition types
listed in Appendices of [GR833] for a list of example strings.
Note length includes padding.
Multiple Error String TLVs may be included in an object.
3.1.2. Procedures
This section applies to nodes that support the communication of alarm
information. ALARM_SPEC objects are carried in Path and Resv
messages. Multiple ALARM_SPEC objects MAY be present.
Nodes that support the communication of alarm information, SHOULD
record the information contained in a received ALARM_SPEC for later
use. All ALARM_SPEC objects received in Path messages SHOULD be
passed unmodified downstream in the corresponding Path messages. All
ALARM_SPEC objects received in Resv messages SHOULD be passed
unmodified upstream in the corresponding Resv messages. ALARM_SPEC
objects are merged in transmitted Resv messages by including a copy
of all ALARM_SPEC objects received in corresponding Resv Messages.
To advertise local alarm information, a node generates an ALARM_SPEC
object for each alarm and adds it to both the Path and Resv messages
for the effected LSP. In all cases, appropriate Error Node Address,
Error Code and Error Values MUST be set, see below for a discussion
on Error Code and Error Values. As the InPlace and NotGuilty flags
only have meaning in ERROR_SPEC objects, they SHOULD NOT be set.
TLVs SHOULD be included in the ALARM_SPEC object to identify the
interface, if any, associated with the alarm - the TLVs defined in
[RFC3471] for identifying interfaces in the IF_ID ERROR_SPEC object
[RFC3473] SHOULD be used for this purpose, but note that TLVs type 4
and 5 (component interfaces) are deprecated by [RFC4201] and SHOULD
NOT be used. TLVs SHOULD also be included to indicate the severity
(Severity TLV), the time (Global Timestamp and/or Local Timestamp
TLVs), and a (brief) string (Error String TLV) associated with the
alarm. The reference count TLV MAY also be included to indicate the
number of times an alarm has been repeated at the reporting node.
ALARM_SPEC objects received from other nodes are not effected by the
addition of local ALARM_SPEC objects, i.e., they continue to be
processed as described above. The choice of which alarm or alarms to
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advertise and which to omit is a local policy matter, and may
configurable by the user.
There are two ways to indicate time. A global timestamp TLV is used
to provide an absolute time reference for the occurrence of an alarm.
The local timestamp TLV is used to provide time reference for the
occurrence of an alarm that is relative to other information
advertised by the node. The global timestamp SHOULD be used on nodes
that maintain an absolute time reference. Both timestamp TLVs MAY be
used simultaneously.
Note, ALARM_SPEC objects SHOULD NOT be added to the Path and Resv
states of LSPs that are in "alarm communication inhibited state."
ALARM_SPEC objects MAY be added to the state of LSPs that are in an
"administratively down" state. These states are indicated by the I
and A bits of the Admin_Status object, see Section 3.2.
To remove local alarm information, a node simply removes the matching
locally generated ALARM_SPEC objects from the outgoing Path and Resv
messages. A node MAY modify a locally generated ALARM_SPEC object.
Normal refresh and trigger message processing applies to Path or Resv
messages that contain ALARM_SPEC objects. Note that changes in
ALARM_SPEC objects from one message to the next may include a
modification in the contents of a specific ALARM_SPEC object, or a
change in the number of ALARM_SPEC objects present. All changes in
ALARM_SPEC objects SHOULD be processed as trigger messages.
Failure to follow the above directives, in particular the ones
labeled "SHOULD" and "SHOULD NOT", may result in the alarm
information not being properly or fully communicated.
3.1.3. Error Codes and Values
The Error Codes and Values used in ALARM_SPEC objects are the same as
those used in ERROR_SPEC objects. New Error Code values for use with
both ERROR_SPEC and ALARM_SPEC objects may be assigned to support
alarm types defined by other standards.
In this document we define one new Error Code. The Error Code uses
the value TBA (by IANA) and is referred to as "Alarms". The values
used in the Error Values field are the same as the values used for
IANAItuProbableCause in the Alarm MIB [RFC3877]. Note these values
are managed by IANA, see http://www.iana.org.
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3.1.4. Backwards Compatibility
The support of ALARM_SPEC objects is optional. Non-supporting nodes
will pass the objects through the node unmodified, because the
ALARM_SPEC object has a C-Num of the form 11bbbbbb.
This allows alarm information to be collected and examined in a
network built from a collection of nodes some of which support the
communication of alarm information, and some of which do not.
3.2. Controlling Alarm Communication
Alarm information communication is controlled via Administrative
Status Information as carried in the Admin_Status object. A new bit
is defined, called the I bit, that indicates when alarm communication
is to be inhibited. The definition of this bit does not modify the
procedures defined in Section 7 of [RFC3473].
3.2.1. Updated Admin Status Object
The format of the Admin_Status object is updated to include the I
bit:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Length | Class-Num(196)| C-Type (1) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|R| Reserved |I| |T|A|D|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Inhibit Alarm Communication (I): 1 bit
When set, indicates that alarm communication is disabled for
the LSP and that nodes SHOULD NOT add local alarm information.
See section 7.1 of [RFC3473] for the definition of the remaining
bits.
3.2.2. Procedures
The I bit may be set and cleared using the procedures defined in
Sections 7.2 and 7.3 of [RFC3473]. A node that receives (or
generates) an Admin_Status object with the A or I bits set (1),
SHOULD remove all locally generated alarm information from the
matching LSP's outgoing Path and Resv messages. When a node receives
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(or generates) an Admin_Status object with the A and I bits clear (0)
and there is local alarm information present, it SHOULD add the local
alarm information to the matching LSP's outgoing Path and Resv
messages.
The processing of non-locally generated ALARM_SPEC objects MUST NOT
be impacted by the contents of the Admin_Status object, that is,
received ALARM_SPEC objects MUST be forwarded unchanged regardless of
the received or transmitted settings of the I and A-bits. Note, per
[RFC3473], the absence of the Admin_Status object is equivalent to
receiving an object containing values all set to zero (0).
I bit related processing behavior MAY be overridden locally based on
configuration.
When generating Notify messages for LSPs with the I bit set, the TLVs
described in this document MAY be added to the ERROR_SPEC object sent
in the the Notify message.
3.3. Message Formats
This section presents the RSVP message related formats as modified by
this document. The formats specified in [RFC3473] served as the
basis of these formats. The objects are listed in suggested
ordering.
The format of a Path message is as follows:
<Path Message> ::= <Common Header> [ <INTEGRITY> ]
[ [<MESSAGE_ID_ACK> | <MESSAGE_ID_NACK>] ... ]
[ <MESSAGE_ID> ]
<SESSION> <RSVP_HOP>
<TIME_VALUES>
[ <EXPLICIT_ROUTE> ]
<LABEL_REQUEST>
[ <PROTECTION> ]
[ <LABEL_SET> ... ]
[ <SESSION_ATTRIBUTE> ]
[ <NOTIFY_REQUEST> ]
[ <ADMIN_STATUS> ]
[ <POLICY_DATA> ... ]
[ <ALARM_SPEC> ... ]
<sender descriptor>
<sender descriptor> is not modified by this document.
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The format of a Resv message is as follows:
<Resv Message> ::= <Common Header> [ <INTEGRITY> ]
[ [<MESSAGE_ID_ACK> | <MESSAGE_ID_NACK>] ... ]
[ <MESSAGE_ID> ]
<SESSION> <RSVP_HOP>
<TIME_VALUES>
[ <RESV_CONFIRM> ] [ <SCOPE> ]
[ <NOTIFY_REQUEST> ]
[ <ADMIN_STATUS> ]
[ <POLICY_DATA> ... ]
[ <ALARM_SPEC> ... ]
<STYLE> <flow descriptor list>
<flow descriptor list> is not modified by this document.
3.4. Relationship to GMPLS UNI
[RFC4208] defines how GMPLS may be used in an overlay model to
provide a user-to-network interface. In this model, restrictions may
be applied to the information that is signaled between an edge-node
and a core-node. This restriction allows the core network to limit
the information that is visible outside of the core. This restriction
may be made for confidentiality, privacy or security reasons. It may
also be made for operational reasons, for example if the information
is only applicable within the core network.
The extensions described in this document are candidates for
filtering as described in [RFC4208]. In particular the following
observations apply.
o An ingress or egress core-node MAY filter alarms from the GMPLS
core to a client-node UNI LSP. This may be to protect information
about the core network, or to indicate that the core network is
performing or has completed recovery actions for the GMPLS LSP.
o An ingress or egress core-node MAY modify alarms from the GMPLS
core when sending to a client-node UNI LSP. This may facilitate
the UNI client's ability to understand the failure and its effect
on the data plane, and enable the UNI client to take corrective
actions in a more-appropriate manner.
o Similarly, an egress core-node MAY choose to not request alarm
reporting on Path messages that it sends downstream to the overlay
network.
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3.5. Relationship to GMPLS E-NNI
GMPLS may be used at the external network-to-network (E-NNI)
interface, see [ASON-APPL]. At this interface, restrictions may be
applied to the information that is signaled between an egress and an
ingress core-node.
This restriction allows the ingress core network to limit the
information that is visible outside of its core network. This
restriction may be made for confidentiality, privacy or security
reasons. It may also be made for operational reasons, for example if
the information is only applicable within the core network.
The extensions described in this document are candidates for
filtering as described in [ASON-APPL]. In particular the following
observations apply.
o An ingress or egress core-node MAY filter internal core network
alarms. This may be to protect information about the internal
network, or to indicate that the core network is performing or has
completed recovery actions for this LSP.
o An ingress or egress core-node MAY modify internal core network
alarms. This may facilitate the peering E-NNI (i.e. the egress
core-node) to understand the failure and its effect on the data
plane, and take corrective actions in a more-appropriate manner or
prolong the generated alarms upstream/downstream as appropriated.
o Similarly, an egress/ingress core-node MAY choose to not request
alarm reporting on Path messages that it sends downstream.
.Pa "Acknowledgments"
Valuable comments and input were received from a number of people,
including Wes Doonan, Bert for the DISMAN reference, Tom Petch for
getting the disman WG interactions started. We also thank David
Black for his valuable comments.
4. Security Considerations
Some operators may consider alarm information as sensitive. To
support environments where this is the case, implementations SHOULD
allow the user to disable the generation of ALARM_SPEC objects, or to
filter or correlate them at domain boundaries.
This document introduces no additional security considerations. See
[RFC3473] for relevant security considerations.
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It may be noted that if the security considerations of [RFC3473] are
breached, alarm information may be spoofed. Such spoofing would be at
most annoying and cause slight degradation of control plane
performance since the details are provided for information only and
do not result in protocol actions beyond the exchange of messages to
convey the information. If the protocol security is able to be
breached sufficiently to allow spoofing of alarm information then
considerably more interesting and exciting damage can be caused by
spoofing other elements of the protocol messages.
5. IANA Considerations
IANA is requested to administer assignment of new values for
namespaces defined in this document and reviewed in this section.
This section uses the terminology of BCP 26 "Guidelines for Writing
an IANA Considerations Section in RFCs" [BCP26].
This document defines a new RSVP "ALARM_SPEC object" with a Class-Num
of the form 11bbbbbb, see section 3.1. The value 197 is suggested.
The C-type values associated with this object should read "Same
values as ERROR_SPEC (C-Num 6), with the exception of C-Types 1 and 2
which are reserved". The text associated with ALARM_SPEC object
should also read "The ALARM_SPEC object uses the Error Code and
Values from the ERROR_SPEC object."
Additionally, Section 3.1.3 defines a new RSVP Error Code. The Error
Code is "Alarms" and uses Error Values defined in the Alarm MIB
[RFC3877]. The suggested Error Code value is 28.
This document also defines the TLVs for use with the RSVP IF_ID
ERROR_SPEC objects defined in [RFC3473]. The following are the TLV
descriptions and (suggested) type values listed in Section 3.1.1:
Type Length Description
----------------------------------
512 8 REFERENCE_COUNT
513 8 SEVERITY
514 8 GLOBAL_TIMESTAMP
515 8 LOCAL_TIMESTAMP
516 variable ERROR_STRING
Note that the type values are not sequential with existing RSVP IF_ID
ERROR_SPEC object TLV assignments. This is intentional and is
intended to provide space for future error TLVs.
This document also defines the I bit in the Admin Status Object, see
Section 3.2.1. This bit field was originally defined in Section 7.1
of [RFC3473]. We request IANA to begin managing assignment of bits
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in the Admin Status Object, and that the bits be allocated through
IETF Consensus actions. Within the 32 bit field in the Admin Status
Object, the defined bits are:
Value Name Reference
---------- --------------------------------- -----------------
0x80000000 Reflect (R) [RFC3473/RFC3471]
0x00000010 Inhibit Alarm Communication (I) [This document]
0x00000004 Testing (T) [RFC3473/RFC3471]
0x00000002 Administratively down (A) [RFC3473/RFC3471]
0x00000001 Deletion in progress (D) [RFC3473/RFC3471]
6. References
6.1. Normative References
[RFC3471] Berger, L., Editor, "Generalized Multi-Protocol
Label Switching (GMPLS) Signaling Functional
Description", RFC 3471, January 2003.
[RFC3473] Berger, L., Editor, "Generalized Multi-Protocol Label
Switching (GMPLS) Signaling - Resource ReserVation
Protocol-Traffic Engineering (RSVP-TE) Extensions",
RFC 3473, January 2003.
[RFC3877] Chisholm, S., Romascanu, D., "Alarm Management
Information Base (MIB)", RFC 3877, September 2004.
[M.3100] ITU Recommendation M.3100, "Generic Network Information
Model", 1995
6.2. Informative References
[RFC4201] Kompella, K., Rekhter, Y., Berger, L., "Link Bundling
in MPLS Traffic Engineering (TE)", RFC 4201, October 2005.
[M.20] ITU-T, "MAINTENANCE PHILOSOPHY FOR TELECOMMUNICATION
NETWORKS", Recommendation M.20, October 1992.
[GR833] Bellcore, "Network Maintenance: Network Element and
Transport Surveillance Messages" (GR-833-CORE), Issue 3,
February 1999.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels," RFC 2119.
Berger, et. al. [Page 16]
Internet Draft draft-ietf-ccamp-gmpls-alarm-spec-04.txt August 2006
[RFC4208] Swallow, G., Drake, J., Ishimatsu, H., and Rekhter, Y.
"Generalized Multiprotocol Label Switching (GMPLS)
User-Network Interface (UNI): Resource ReserVation
Protocol-Traffic Engineering (RSVP-TE) Support for the
Overlay Model", RFC 4208, October 2005.
[ASON-APPL] D. Papadimitriou et. al., "Generalized MPLS (GMPLS)
RSVP-TE signaling usage in support of Automatically
Switched Optical Network (ASON),"
draft-ietf-ccamp-gmpls-rsvp-te-ason, work in progress.
7. Contributors
Contributors are listed in alphabetical order:
Lou Berger Deborah Brungard
LabN Consulting, L.L.C. AT&T Labs, Room MT D1-3C22
200 Laurel Avenue
Middletown, NJ 07748, USA
Phone: +1 301-468-9228 Phone: (732) 420-1573
Email: lberger@labn.net Email: dbrungard@att.com
Igor Bryskin Adrian Farrel
Movaz Networks, Inc. Old Dog Consulting
7926 Jones Branch Drive
Suite 615
McLean VA, 22102, USA Phone: +44 (0) 1978 860944
Email: ibryskin@movaz.com Email: adrian@olddog.co.uk
Dimitri Papadimitriou (Alcatel) Arun Satyanarayana
Francis Wellesplein 1 Cisco Systems, Inc
B-2018 Antwerpen, Belgium 170 West Tasman Dr.
San Jose, CA 95134 USA
Phone: +32 3 240-8491 Phone: +1 408 853-3206
Email: dimitri.papadimitriou@alcatel.be Email: asatyana@cisco.com
8. Contact Address
Lou Berger
LabN Consulting, L.L.C.
Phone: +1 301-468-9228
Email: lberger@labn.net
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9. Full Copyright Statement
Copyright (C) The Internet Society (2006). This document is subject
to the rights, licenses and restrictions contained in BCP 78, and
except as set forth therein, the authors retain all their rights.
This document and the information contained herein are provided on an
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OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED,
INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE
INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
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Berger, et. al. [Page 18]
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