rfc9885.original   rfc9885.txt 
LSR Working Group P. Kaneriya Internet Engineering Task Force (IETF) P. Kaneriya
Internet-Draft T. Li Request for Comments: 9885 T. Li
Intended status: Standards Track A. Przygienda Category: Standards Track A. Przygienda
Expires: 25 December 2025 S. Hegde ISSN: 2070-1721 S. Hegde
Juniper Networks Juniper Networks
L. Ginsberg L. Ginsberg
Cisco Systems Cisco Systems
23 June 2025 October 2025
Multi-Part TLVs in IS-IS Multi-Part TLVs in IS-IS
draft-ietf-lsr-multi-tlv-19
Abstract Abstract
New technologies are adding new information into IS-IS while New technologies are adding new information into IS-IS while
deployment scales are simultaneously increasing. This causes the deployment scales are simultaneously increasing. This causes the
contents of many critical TLVs to exceed the currently supported contents of many critical TLVs to exceed the currently supported
limit of 255 octets. This document codifies the common mechanism of limit of 255 octets. This document codifies the common mechanism of
extending the TLV content space through multiple TLVs. extending the TLV content space through multiple TLVs.
Status of This Memo Status of This Memo
This Internet-Draft is submitted in full conformance with the This is an Internet Standards Track document.
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months This document is a product of the Internet Engineering Task Force
and may be updated, replaced, or obsoleted by other documents at any (IETF). It represents the consensus of the IETF community. It has
time. It is inappropriate to use Internet-Drafts as reference received public review and has been approved for publication by the
material or to cite them other than as "work in progress." Internet Engineering Steering Group (IESG). Further information on
Internet Standards is available in Section 2 of RFC 7841.
This Internet-Draft will expire on 25 December 2025. Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
https://www.rfc-editor.org/info/rfc9885.
Copyright Notice Copyright Notice
Copyright (c) 2025 IETF Trust and the persons identified as the Copyright (c) 2025 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents (https://trustee.ietf.org/ Provisions Relating to IETF Documents
license-info) in effect on the date of publication of this document. (https://trustee.ietf.org/license-info) in effect on the date of
Please review these documents carefully, as they describe your rights publication of this document. Please review these documents
and restrictions with respect to this document. Code Components carefully, as they describe your rights and restrictions with respect
extracted from this document must include Revised BSD License text as to this document. Code Components extracted from this document must
described in Section 4.e of the Trust Legal Provisions and are include Revised BSD License text as described in Section 4.e of the
provided without warranty as described in the Revised BSD License. Trust Legal Provisions and are provided without warranty as described
in the Revised BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction
2. Requirements Language . . . . . . . . . . . . . . . . . . . . 4 2. Requirements Language
3. Overview of MP-TLV Applicability to TLVs . . . . . . . . . . 4 3. Overview of MP-TLV Applicability to TLVs
3.1. TLVs That Advertise a List of Objects . . . . . . . . . . 4 3.1. TLVs that Advertise a List of Objects
3.2. TLVs That Advertise Objects with Identifier(s) . . . . . 5 3.2. TLVs that Advertise Objects with Identifier(s)
3.2.1. Example: Extended IS Reachability . . . . . . . . . . 5 3.2.1. Example: Extended IS Reachability
3.2.2. Example: Extended IP Reachability . . . . . . . . . . 5 3.2.2. Example: Extended IP Reachability
4. Multi-Part TLVs . . . . . . . . . . . . . . . . . . . . . . . 6 4. Multi-Part TLVs
5. Procedure for Receiving Multi-Part TLVs . . . . . . . . . . . 6 5. Procedure for Receiving Multi-Part TLVs
6. Specification of Applicability of Multi-Part TLV . . . . . . 8 6. Specification of Applicability of Multi-Part TLVs
7. MP-TLV Capability Advertisement . . . . . . . . . . . . . . . 8 7. MP-TLV Capability Advertisement
8. Deployment Considerations . . . . . . . . . . . . . . . . . . 10 8. Deployment Considerations
8.1. Controls and Alarms . . . . . . . . . . . . . . . . . . . 10 8.1. Controls and Alarms
8.2. Restrictions on Generation of MP-TLVs . . . . . . . . . . 10 8.2. Restrictions on Generation of MP-TLVs
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11 9. IANA Considerations
9.1. MP-TLV Support sub-TLV . . . . . . . . . . . . . . . . . 11 9.1. MP-TLV Support Sub-TLV
9.2. Extension to IS-IS Top Level TLV Registries . . . . . . . 11 9.2. Extension to IS-IS Top-Level TLV Registries
9.2.1. MP-TLV for IS-IS Top-Level TLV Codepoints . . . . . . 11 9.2.1. MP-TLV for IS-IS Top-Level TLV Codepoints
9.2.2. MP-TLV for IS-IS Sub-TLVs for Reverse Metric TLV . . 15 9.2.2. MP-TLV for IS-IS Sub-TLVs for Reverse Metric TLV
9.2.3. MP-TLV for IS-IS Sub-TLVs for TLVs Advertising Neighbor 9.2.3. MP-TLV for IS-IS Sub-TLVs for TLVs Advertising Neighbor
Information . . . . . . . . . . . . . . . . . . . . . 16 Information
9.2.4. MP-TLV for IS-IS Sub-TLVs for TLVs Advertising Prefix 9.2.4. MP-TLV for IS-IS Sub-TLVs for TLVs Advertising Prefix
Reachability . . . . . . . . . . . . . . . . . . . . 18 Reachability
9.2.5. MP-TLV for IS-IS Sub-TLVs for MT-Capability TLV . . . 19 9.2.5. MP-TLV for IS-IS Sub-TLVs for MT-Capability TLV
9.2.6. MP-TLV for IS-IS Sub-TLVs for IS-IS Router CAPABILITY 9.2.6. MP-TLV for IS-IS Sub-TLVs for IS-IS Router CAPABILITY
TLV . . . . . . . . . . . . . . . . . . . . . . . . . 21 TLV
9.2.7. IS-IS Sub-Sub-TLVs for SRv6 Capabilities Sub-TLV . . 22 9.2.7. IS-IS Sub-Sub-TLVs for SRv6 Capabilities Sub-TLV
9.2.8. MP-TLV IS-IS Sub-Sub-TLVs for BIER Info Sub-TLV . . . 23 9.2.8. MP-TLV IS-IS Sub-Sub-TLVs for BIER Info Sub-TLV
9.2.9. MP-TLV for IS-IS Sub-TLVs for Segment Identifier/Label 9.2.9. MP-TLV for IS-IS Sub-TLVs for Segment Identifier/Label
Binding TLVs . . . . . . . . . . . . . . . . . . . . 23 Binding TLVs
9.2.10. MP-TLV for IS-IS Sub-Sub-TLV Codepoints for 9.2.10. MP-TLV for IS-IS Sub-Sub-TLV Codepoints for
Application-Specific Link Attributes . . . . . . . . 23 Application-Specific Link Attributes
9.2.11. MP-TLV for IS-IS Sub-TLVs for Application-Specific SRLG 9.2.11. MP-TLV for IS-IS Sub-TLVs for Application-Specific SRLG
TLV . . . . . . . . . . . . . . . . . . . . . . . . . 25 TLV
9.2.12. MP-TLV for IS-IS Sub-Sub-TLVs for SRv6 SID 9.2.12. MP-TLV for IS-IS Sub-Sub-TLVs for SRv6 SID Sub-TLVs
Sub-TLVs . . . . . . . . . . . . . . . . . . . . . . 25
9.2.13. MP-TLV for IS-IS Sub-Sub-TLVs for Flexible Algorithm 9.2.13. MP-TLV for IS-IS Sub-Sub-TLVs for Flexible Algorithm
Definition Sub-TLV . . . . . . . . . . . . . . . . . 26 Definition Sub-TLV
9.2.14. MP-TLV for IS-IS Sub-Sub-TLVs for Flood Reflection 9.2.14. MP-TLV for IS-IS Sub-Sub-TLVs for Flood Reflection
Discovery Sub-TLV . . . . . . . . . . . . . . . . . . 27 Discovery Sub-TLV
10. Security Considerations . . . . . . . . . . . . . . . . . . . 27 10. Security Considerations
11. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 27 11. References
12. References . . . . . . . . . . . . . . . . . . . . . . . . . 27 11.1. Normative References
12.1. Normative References . . . . . . . . . . . . . . . . . . 27 11.2. Informative References
12.2. Informative References . . . . . . . . . . . . . . . . . 29 Contributors
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 29 Authors' Addresses
1. Introduction 1. Introduction
The continued growth of the Internet has resulted in a commensurate The continued growth of the Internet has resulted in a commensurate
growth in the scale of service provider networks and the amount of growth in the scale of service provider networks and the amount of
information carried in IS-IS [ISO10589] Type-Length-Value (TLV) information carried in IS-IS [ISO10589] Type-Length-Value (TLV)
tuples. Simultaneously, new traffic engineering technologies are tuples. Simultaneously, new traffic engineering technologies are
defining new attributes, further adding to the scaling pressures. defining new attributes, further adding to the scaling pressures.
The original TLV definition limits each TLV to a maximum of 255 The original TLV definition limits each TLV to a maximum of 255
octets of payload, which is becoming increasingly problematic. octets of payload, which is becoming increasingly problematic.
skipping to change at page 3, line 40 skipping to change at line 129
The intent of this document is to clarify and codify the situation by The intent of this document is to clarify and codify the situation by
explicitly making multiple occurrences of a TLV the standard explicitly making multiple occurrences of a TLV the standard
mechanism for scaling TLV contents. Any future document that mechanism for scaling TLV contents. Any future document that
proposes a different mechanism for scaling TLV contents for a given proposes a different mechanism for scaling TLV contents for a given
codepoint must explain why multiple occurrences of a TLV is not codepoint must explain why multiple occurrences of a TLV is not
appropriate. appropriate.
This document does not alter the encoding of any TLV where multiple This document does not alter the encoding of any TLV where multiple
occurrences of a TLV are already defined. Some examples of this are: occurrences of a TLV are already defined. Some examples of this are:
Router Capability TLV (Type 242) [RFC7981] * Router Capability TLV (Type 242) [RFC7981]
Application-Specific SRLG (Type 238) [RFC9479] * Application-Specific SRLG (Type 238) [RFC9479]
Instance Identifier (type 7) [RFC8202] * Instance Identifier (type 7) [RFC8202]
Application-Specific Link Attributes (sub-TLV Type 16) [RFC9479] * Application-Specific Link Attributes (sub-TLV Type 16) [RFC9479]
[RFC7356] has defined a 16-bit length field for TLVs in flooding [RFC7356] has defined a 16-bit length field for TLVs in flooding
scoped Protocol Data Units (PDUs), in which case the problem scoped Protocol Data Units (PDUs), in which case the problem
addressed by this document would not exist. However, introduction of addressed by this document would not exist. However, introduction of
these new PDU types is not backwards compatible. Therefore, there is these new PDU types is not backwards compatible. Therefore, there is
a need to address how to expand the information advertised in a need to address how to expand the information advertised in
existing PDUs that use 8-bit length TLVs. existing PDUs that use 8-bit length TLVs.
The mechanism described in this document has not been documented for The mechanism described in this document has not been documented for
all TLVs previously. This document provides the necessary protocol all TLVs previously. This document provides the necessary protocol
skipping to change at page 4, line 28 skipping to change at line 160
mechanism has been previously explicitly specified, and defines this mechanism has been previously explicitly specified, and defines this
mechanism as the default extension mechanism for future TLVs. The mechanism as the default extension mechanism for future TLVs. The
mechanism described in this document is applicable to top level TLVs mechanism described in this document is applicable to top level TLVs
as well as any level of sub-TLVs that may appear within a top level as well as any level of sub-TLVs that may appear within a top level
TLV. TLV.
2. Requirements Language 2. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP "OPTIONAL" in this document are to be interpreted as described in
14 [RFC2119] [RFC8174] when, and only when, they appear in all BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here. capitals, as shown here.
3. Overview of MP-TLV Applicability to TLVs 3. Overview of MP-TLV Applicability to TLVs
A TLV is a tuple of (Type, Length, Value) and can be advertised in A TLV is a tuple of (Type, Length, Value) and can be advertised in
IS-IS packets. Both Type and Length fields are one octet in size, IS-IS packets. Both Type and Length fields are one octet in size,
which leads to the limitation that a maximum of 255 octets can be which leads to the limitation that a maximum of 255 octets can be
sent in a single TLV. TLVs that have certain general characteristics sent in a single TLV. TLVs that have certain general characteristics
have the potential to require advertisement of more than 255 octets. have the potential to require advertisement of more than 255 octets.
These generic types are described in more detail in the following These generic types are described in more detail in the following
sub-sections. subsections.
3.1. TLVs That Advertise a List of Objects 3.1. TLVs that Advertise a List of Objects
Some TLVs are simply a list of objects of a given type. For example, Some TLVs are simply a list of objects of a given type. For example,
the BFD-Enabled TLV (type 148) [RFC6213] contains a list of Multi- the BFD-Enabled TLV (Type 148) [RFC6213] contains a list of Multi-
Topology Identifier (MTID)/ Network Layer Protocol Identifier (NLPID) Topology Identifier (MTID)/ Network Layer Protocol Identifier (NLPID)
pairs. If more than 255 octets are required to advertise all of the pairs. If more than 255 octets are required to advertise all of the
MTID/NLPID pairs, multiple BFD-Enabled TLVs would be required. The MTID/NLPID pairs, multiple BFD-Enabled TLVs would be required. The
relationship between multiple BFD-Enabled TLVs is established using relationship between multiple BFD-Enabled TLVs is established using
the TLV type. the TLV type.
3.2. TLVs That Advertise Objects with Identifier(s) 3.2. TLVs that Advertise Objects with Identifier(s)
Some TLVs support advertisement of objects of a given type, where Some TLVs support advertisement of objects of a given type, where
each object is identified by a unique set of identifiers. In this each object is identified by a unique set of identifiers. In this
case the "key" that uniquely identifies a given object consists of case, the "key" that uniquely identifies a given object consists of
the set of identifiers. the set of identifiers.
3.2.1. Example: Extended IS Reachability 3.2.1. Example: Extended IS Reachability
As an example, consider the Extended IS Reachability TLV (type 22) As an example, consider the Extended IS Reachability TLV (Type 22)
[RFC5305]. A neighbor in this TLV is specified by: [RFC5305]. A neighbor in this TLV is specified by:
* 7 octets of system ID and pseudonode number * 7 octets of a system ID and pseudonode number
* 3 octets of default metric * 3 octets of a default metric
* Optionally one or more of the following link identifiers encoded * Optionally, one or more of the following link identifiers encoded
as sub-TLVs: as sub-TLVs:
- IPv4 interface address and IPv4 neighbor address as specified - an IPv4 interface address and IPv4 neighbor address as
in [RFC5305] specified in [RFC5305]
- IPv6 interface address and IPv6 neighbor address as specified - an IPv6 interface address and IPv6 neighbor address as
in [RFC6119] specified in [RFC6119]
- Link Local/Remote Identifiers as specified in [RFC5307] - Link Local/Remote Identifiers as specified in [RFC5307]
The key consists of the 7 octets of system ID and pseudonode number The key consists of the 7 octets of system ID and pseudonode number
plus the set of link identifiers that are present. plus the set of link identifiers that are present.
3.2.2. Example: Extended IP Reachability 3.2.2. Example: Extended IP Reachability
As another example, consider the Extended IP Reachability TLV (type As another example, consider the Extended IP Reachability TLV (Type
135) [RFC5305]. A prefix in this TLV is specified by: 135) [RFC5305]. A prefix in this TLV is specified by:
* 4 octets of metric information * 4 octets of metric information
* 1 octet of control information that includes 6 bits specifying the * 1 octet of control information that includes 6 bits specifying the
prefix length prefix length
* 0-4 octets of IPv4 prefix * 0-4 octets of an IPv4 prefix
followed by up to 250 octets of sub-TLV information. The above are followed by up to 250 octets of sub-TLV information.
The key consists of the 6 bits of prefix length plus 0-4 octets of The key consists of the 6 bits of prefix length plus 0-4 octets of an
IPv4 prefix. IPv4 prefix.
4. Multi-Part TLVs 4. Multi-Part TLVs
If a router advertises multiple TLV tuples with the same TLV type and If a router advertises multiple TLV tuples with the same TLV type and
the same key (when applicable) in an IS-IS Hello (IIH) packet or in the same key (when applicable) in an IS-IS Hello (IIH) packet or in
the set of LSPs for a given level, they are considered a Multi-Part the set of LSPs for a given level, they are considered a Multi-Part
TLV (MP-TLV). TLV (MP-TLV).
In the absence of MP-TLV support, when a router receives an MP-TLV, In the absence of MP-TLV support, when a router receives an MP-TLV,
skipping to change at page 6, line 38 skipping to change at line 264
NOTE: This document intentionally does not include a definition of NOTE: This document intentionally does not include a definition of
the key for each codepoint. To do so would be redundant and risk the key for each codepoint. To do so would be redundant and risk
unintentionally deviating from the definition that already exists in unintentionally deviating from the definition that already exists in
the relevant specifications. Also, the term "key" is a generic term the relevant specifications. Also, the term "key" is a generic term
that is not used in the relevant specifications. that is not used in the relevant specifications.
Each TLV that is part of an MP-TLV MUST be parsable independent of Each TLV that is part of an MP-TLV MUST be parsable independent of
other TLVs in the MP-TLV. Breaking of a single sub-TLV or other data other TLVs in the MP-TLV. Breaking of a single sub-TLV or other data
unit across TLVs MUST NOT be done. Breaking of a data unit across unit across TLVs MUST NOT be done. Breaking of a data unit across
TLVs results in an invalid encoding. Guidelines to receivers for TLVs results in an invalid encoding. Guidelines to receivers for
handling such a case are specified in [RFC8918] handling such a case are specified in [RFC8918].
5. Procedure for Receiving Multi-Part TLVs 5. Procedure for Receiving Multi-Part TLVs
A router that receives a MP-TLV MUST accept all of the information in A router that receives an MP-TLV MUST accept all of the information
all of the parts. The order of arrival and placement of the TLV in all of the parts. The order of arrival and placement of the TLV
parts in LSP fragments is irrelevant. Multiple TLV parts MAY occur parts in LSP fragments is irrelevant. Multiple TLV parts MAY occur
in a single LSP or parts MAY occur in different LSPs. in a single LSP or parts MAY occur in different LSPs.
The placement of the TLV parts in an IIH is irrelevant. The placement of the TLV parts in an IIH is irrelevant.
When processing MP-TLVs, implementations MUST NOT impose a minimum When processing MP-TLVs, implementations MUST NOT impose a minimum
length check. Although MP-TLVs SHOULD NOT be sent unless the length check. Although MP-TLVs SHOULD NOT be sent unless the
capacity of a single TLV (255 octets) is exceeded, receivers MUST NOT capacity of a single TLV (255 octets) is exceeded, receivers MUST NOT
reject MP-TLVs if senders do not strictly adhere to this constraint. reject MP-TLVs if senders do not strictly adhere to this constraint.
For example, if two MP-TLVs are received, each of which has a length For example, if two MP-TLVs are received, each of which has a length
of 100 bytes, the fact that the total amount of data does not exceed of 100 bytes, the fact that the total amount of data does not exceed
255 bytes MUST NOT cause the TLVs to be rejected. See Section 8.2 255 bytes MUST NOT cause the TLVs to be rejected. See Section 8.2
for guidance when sending MP-TLVs. for guidance on sending MP-TLVs.
The contents of a MP-TLV MUST be processed as if they were The contents of an MP-TLV MUST be processed as if they were
concatenated. If the internals of the TLV contain key information, concatenated. If the internals of the TLV contain key information,
then replication of the key information MUST be taken to indicate then replication of the key information MUST be taken to indicate
that subsequent data MUST be processed as if the subsequent data were that subsequent data MUST be processed as if the subsequent data were
concatenated after a single copy of the key information. concatenated after a single copy of the key information.
For example, suppose that a router receives an LSP with a Multi-Part For example, suppose that a router receives an LSP with a Multi-Part
Extended IS Reachability TLV. The first part contains key Extended IS Reachability TLV. The first part contains key
information K with unique sub-TLVs A, B, and C. The second part information K with unique sub-TLVs A, B, and C. The second part
contains key information K with unique sub-TLVs D, E, and F. The contains key information K with unique sub-TLVs D, E, and F. The
receiving router must then process this as having key information K receiving router must then process this as having key information K
and unique sub-TLVs A, B, C, D, E, F, or, because ordering is and unique sub-TLVs A, B, C, D, E, F, or, because ordering is
irrelevant, unique sub-TLVs D, E, F, A, B, C, or any other irrelevant, unique sub-TLVs D, E, F, A, B, C, or any other
permutation. permutation.
A TLV may contain information in its fixed part that is not part of A TLV may contain information in its fixed part that is not part of
the key. For example, the metric in both the Extended IS the key. For example, the metric in both the Extended IS
Reachability TLV and the Extended IP Reachability TLV does not Reachability TLV and the Extended IP Reachability TLV does not
specify which object the TLV refers to, and thus is not part of the specify which object the TLV refers to, and thus is not part of the
key. Having inconsistent information in different parts of a MP-TLV key. Having inconsistent information in different parts of an MP-TLV
is an error. is an error.
It is also possible that information that is not part of the fixed It is also possible that information that is not part of the fixed
part of a TLV can be duplicated e.g., a sub-TLV that is intended to part of a TLV can be duplicated, e.g., a sub-TLV that is intended to
only appear once appears multiple times and has inconsistent values. only appear once appears multiple times and has inconsistent values.
This could occur within the same TLV or in different parts of an MP- This could occur within the same TLV or in different parts of an MP-
TLV. This is also an error. TLV. This is also an error.
Specifying how to handle such cases is the responsibility of the The document defining the TLV should specify how to handle such
document that defines the TLV. If such a document is not explicit in cases. If such a document is not explicit in how to handle such
how to handle such cases, the following procedure is defined: cases, the following procedure is defined:
* The first occurrence in the lowest numbered LSP is used. * The first occurrence in the lowest numbered LSP is used.
Subsequent occurrences in the same LSP or higher numbered LSPs are Subsequent occurrences in the same LSP or higher numbered LSPs are
ignored. ignored.
* In the case of IIHs, the first occurrence in the IIH is used. * In the case of IIHs, the first occurrence in the IIH is used.
Subsequent occurrences in the IIH are ignored. Subsequent occurrences in the IIH are ignored.
6. Specification of Applicability of Multi-Part TLV 6. Specification of Applicability of Multi-Part TLVs
As mentioned in Section 1, existing specifications for some TLVs have As mentioned in Section 1, existing specifications for some TLVs have
explicitly stated that the use of MP-TLV procedures are applicable to explicitly stated that the use of MP-TLV procedures are applicable to
that codepoint. However, MP-TLV procedures are potentially that codepoint. However, MP-TLV procedures are potentially
applicable to any codepoint that allows sub-TLVs to be included as applicable to any codepoint that allows sub-TLVs to be included as
part of the information advertised. MP-TLV procedures may also be part of the information advertised. MP-TLV procedures may also be
applicable to codepoints that do not support sub-TLVs, but which applicable to codepoints that do not support sub-TLVs, but which
define an unbounded number of attributes that may be advertised define an unbounded number of attributes that may be advertised
within a single codepoint. An example of the latter is GMPLS-SRLG as within a single codepoint. An example of the latter is GMPLS-SRLG as
defined in [RFC5307]. defined in [RFC5307].
The lack of explicit indication of applicability of MP-TLV procedures The lack of explicit indication of applicability of MP-TLV procedures
to all codepoints to which such procedures could be applied for all codepoints to which such procedures could be applied
contributes to potential interoperability problems if/when the need contributes to potential interoperability problems if/when there is
arises to advertise more than 255 octets of information for such a need to advertise more than 255 octets of information for such a
codepoint. codepoint.
This document makes explicit the applicability of MP-TLV procedures This document makes explicit the applicability of MP-TLV procedures
for all existing codepoints defined for the IS-IS protocol by for all existing codepoints defined for the IS-IS protocol by
extending existing and relevant IANA protocol registries to include extending existing and relevant IANA protocol registries to include
an explicit indication of applicability of MP-TLV procedures for each an explicit indication of applicability of MP-TLV procedures for each
codepoint. See Section 9. Therefore any new codepoints defined by codepoint. See Section 9. Therefore, any new codepoints defined by
future protocol extensions will explicitly indicate the applicability future protocol extensions will explicitly indicate the applicability
of MP-TLV procedures to the new codepoints. of MP-TLV procedures to the new codepoints.
7. MP-TLV Capability Advertisement 7. MP-TLV Capability Advertisement
Introduction of the use of MP-TLV for codepoints where the existing Introduction of the use of MP-TLV for codepoints where the existing
specifications have not explicitly defined MP-TLV support can be specifications have not explicitly defined MP-TLV support can be
extremely disruptive to network operations in cases where not all extremely disruptive to network operations in cases where not all
routers in the network support MP-TLV for those codepoints. Partial routers in the network support MP-TLV for those codepoints. Partial
deployment can easily result in traffic loss and/or other unexpected deployment can easily result in traffic loss and/or other unexpected
behaviors that may be hard to diagnose. behaviors that may be hard to diagnose.
For example, if there are mutiple TLVs associated with the For example, if there are multiple TLVs associated with the
advertisement of a neighbor and an implementation does not process advertisement of a neighbor and an implementation does not process
all of the link attributes advertised, then constrained path all of the link attributes advertised, then constrained path
calculations based on those attributes are likely to produce calculations based on those attributes are likely to produce
incorrect or unexpected results. This could produce forwarding loops incorrect or unexpected results. This could produce forwarding loops
or dropped traffic. or dropped traffic.
As an aid to network operators when diagnosing such situations, a new As an aid to network operators when diagnosing such situations, a new
sub-TLV of the IS-IS Router CAPABILITY TLV [RFC7981] is defined: sub-TLV of the IS-IS Router CAPABILITY TLV [RFC7981] is defined:
MP-TLV Support for TLVs with implicit support MP-TLV Support for TLVs with implicit support
Type 30 (suggested - to be assigned by IANA) 1 octet Type: 30 (1 octet)
Length 0 1 octet Length: 0 (1 octet)
Routers that support MP-TLV for codepoints for which existing Routers that support MP-TLV for codepoints for which existing
specifications do not explicitly define such support, but for which specifications do not explicitly define such support, but for which
MP-TLV is applicable, SHOULD include this sub-TLV in a Router MP-TLV is applicable, SHOULD include this sub-TLV in a Router
Capability TLV. Capability TLV.
Scope of the associated Router Capability TLV is per level (S-bit Scope of the associated Router Capability TLV is per level (S-bit
clear). clear).
This advertisement is for informational purposes only. IS-IS This advertisement is for informational purposes only. IS-IS
protocol implementations MUST NOT alter what is sent or how what is protocol implementations MUST NOT alter what is sent or how what is
received is processed based on these advertisements. received is processed based on these advertisements.
The sub-TLV intentionally does not provide a syntax to specify MP-TLV The sub-TLV intentionally does not provide a syntax to specify MP-TLV
support on a per-codepoint basis. It is presumed that if such support on a per-codepoint basis. It is presumed that if such
support is provided that it applies to all relevant codepoints. It support is provided that it applies to all relevant codepoints. It
is understood that in reality, a given implementation might limit MP- is understood that in reality, a given implementation might limit MP-
TLV support to particular codepoints based on the needs of the TLV support to particular codepoints based on the needs of the
deployment scenarios in which it is used. Therefore, diligence is deployment scenarios in which it is used. Therefore, diligence is
still required on the part of the operator to ensure that still required on the part of the operator to ensure that
configurations which require the sending of MP-TLV for a given configurations which require the sending of an MP-TLV for a given
codepoint are not introduced on any router in the network until all codepoint are not introduced on any router in the network until all
routers in the network support MP-TLV for the relevant codepoints. routers in the network support MP-TLV for the relevant codepoints.
The Router Capability TLV is meant to advertise capabilities that are The Router Capability TLV is meant to advertise capabilities that are
of direct use to the IS-IS protocol. The MP-TLV Support sub-TLV of direct use to the IS-IS protocol. The MP-TLV Support sub-TLV
advertises management information, not of direct use to the protocol. advertises management information, which is not of direct use to the
The intent is to provide information that may be of use to a network protocol. The intent is to provide information that may be of use to
operator. This exception to the intended use of the Router a network operator. This exception to the intended use of the Router
Capability TLV is introduced to help mitigate the potential Capability TLV is introduced to help mitigate the potential
disruptiveness associated with the introduction of MP-TLV support in disruptiveness associated with the introduction of MP-TLV support in
cases where such support has not been explicitly defined. This is cases where such support has not been explicitly defined. This is
not intended to introduce a generic new use case for the Router not intended to introduce a generic new use case for the Router
Capability TLV. Capability TLV.
NOTE: A more appropriate and robust mechanism to provide detailed NOTE: A more appropriate and robust mechanism to provide detailed
information on what a given implementation supports is to utilize information on what a given implementation supports is to utilize
YANG to define Protocol Implementation Conformance Statement (PICS). YANG to define Protocol Implementation Conformance Statement (PICS).
An example of this can be found in [I-D.ietf-lsr-isis-pics-yang]. An example of this can be found in [PICS-YANG].
8. Deployment Considerations 8. Deployment Considerations
Sending of MP-TLVs in the presence of routers that do not correctly Sending of MP-TLVs in the presence of routers that do not correctly
process such advertisements can result in interoperability issues, process such advertisements can result in interoperability issues,
including incorrect forwarding of packets. This section discusses including incorrect forwarding of packets. This section discusses
best practices to be used when a deployment requires the use of MP- best practices to be used when a deployment requires the use of MP-
TLVs for codepoints for which existing specifications do not TLVs for codepoints for which existing specifications do not
explicitly indicate MP-TLV support. explicitly indicate MP-TLV support.
skipping to change at page 10, line 25 skipping to change at line 432
implementations provide the means to prevent (or at least make less implementations provide the means to prevent (or at least make less
likely) partial deployment of MP-TLV for a given codepoint, it is likely) partial deployment of MP-TLV for a given codepoint, it is
important to emphasize the need to assist operators in avoiding important to emphasize the need to assist operators in avoiding
inadvertent problematic deployment scenarios. Providing appropriate inadvertent problematic deployment scenarios. Providing appropriate
controls to enable/disable the sending of MP-TLVs as discussed in controls to enable/disable the sending of MP-TLVs as discussed in
Section 8.1 is important to avoid interoperability issues. Section 8.1 is important to avoid interoperability issues.
8.1. Controls and Alarms 8.1. Controls and Alarms
It is RECOMMENDED that implementations that support the sending of It is RECOMMENDED that implementations that support the sending of
MP-TLVs to provide configuration controls that enable/disable MP-TLVs provide configuration controls that enable/disable generation
generation of MP-TLVs. Given that MP-TLV support in a given of MP-TLVs. Given that MP-TLV support in a given implementation may
implementation may vary on a per TLV basis, these controls SHOULD vary on a per-TLV basis, these controls SHOULD provide support at a
support per codepoint granularity. For example, an implementation per-codepoint granularity. For example, an implementation might
might support MP-TLVs for IS Extended Reachability but not for IP support MP-TLVs for IS Extended Reachability but not for IP
Reachability. Reachability.
Implementations that support disablement of MP-TLVs MUST log the Implementations that support disablement of MP-TLVs MUST log the
following occurrences: following occurrences:
* An MP-TLV is received when use of MP-TLVs is disabled. * An MP-TLV is received when use of MP-TLVs is disabled.
* Local LSP generation requires the use of MP-TLVs when generation * Local LSP generation requires the use of MP-TLVs when generation
of MP-TLVs is disabled. of MP-TLVs is disabled.
skipping to change at page 11, line 19 skipping to change at line 472
multiple TLVs unless MP-TLV is applicable to the TLV and the amount multiple TLVs unless MP-TLV is applicable to the TLV and the amount
of information that is required to be sent exceeds the capacity of a of information that is required to be sent exceeds the capacity of a
single TLV. For example, when additional space is required in an single TLV. For example, when additional space is required in an
existing TLV, as long as there is space in the TLV, information existing TLV, as long as there is space in the TLV, information
SHOULD NOT be split into multiple TLVs. If there is no space in the SHOULD NOT be split into multiple TLVs. If there is no space in the
current LSP to fit the now larger TLV, the TLV SHOULD be moved to a current LSP to fit the now larger TLV, the TLV SHOULD be moved to a
new LSP. new LSP.
9. IANA Considerations 9. IANA Considerations
9.1. MP-TLV Support sub-TLV 9.1. MP-TLV Support Sub-TLV
This document requests the following code point from the "IS-IS Sub- IANA has registered the following code point from the "IS-IS Sub-TLVs
TLVs for IS-IS Router CAPABILITY TLV" registry: for IS-IS Router CAPABILITY TLV" registry:
Type: 30 (suggested) Type: 30
Description: MP-TLV Support for TLVs with implicit support Description: MP-TLV Support for TLVs with implicit support
MP-TLV Applicability: N MP-TLV Applicability: N
Reference: This document Section 7.2 Reference: Section 7 of RFC 9885
9.2. Extension to IS-IS Top Level TLV Registries 9.2. Extension to IS-IS Top-Level TLV Registries
This document requests IANA to extend a number of registries under IANA has extended a number of registries under the "IS-IS TLV
the "IS-IS TLV Codepoints" registries Codepoints" registry group (<https://www.iana.org/assignments/isis-
(https://www.iana.org/assignments/isis-tlv-codepoints/isis-tlv- tlv-codepoints/>) to include a column that indicates whether the MP-
codepoints.xhtml) to include a column that indicates whether the MP-
TLV procedures described in this document are applicable to that TLV procedures described in this document are applicable to that
codepoint. "Y" indicates that MP-TLV is applicable. "N" indicates codepoint. "Y" indicates that MP-TLV is applicable. "N" indicates
MP-TLV is not applicable. MP-TLV is not applicable.
The following sub-sections provide the initial contents of the new The following subsections provide the initial contents of the new
column for a number of existing registries. The initial values for column for a number of existing registries. The initial values for
MP-TLV applicability defined in the following sub-sections are based MP-TLV applicability defined in the following subsections are based
on the rule that MP-TLV is applicable to any codepoint that supports on the rule that MP-TLV is applicable to any codepoint that supports
sub-TLVs, without regard to whether the sub-TLVs that are currently sub-TLVs, without regard to whether the sub-TLVs that are currently
defined are sufficient to require MP-TLVs to be sent. defined are sufficient to require MP-TLVs to be sent.
9.2.1. MP-TLV for IS-IS Top-Level TLV Codepoints 9.2.1. MP-TLV for IS-IS Top-Level TLV Codepoints
(https://www.iana.org/assignments/isis-tlv-codepoints/isis-tlv- +===========+====================================+====+
codepoints.xhtml#tlv-codepoints) | Value | Name | MP |
+===========+========================================+====+ +===========+====================================+====+
| Value | Name | MP | | 0 | Reserved | |
+===========+========================================+====+ +-----------+------------------------------------+----+
| 0 | Reserved | | | 1 | Area Addresses | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 1 | Area Addresses | N | | 2 | IIS Neighbors | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 2 | IIS Neighbors | N | | 3 | ES Neighbors | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 3 | ES Neighbors | N | | 4 | Part. DIS | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 4 | Part. DIS | N | | 5 | Prefix Neighbors | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 5 | Prefix Neighbors | N | | 6 | IIS Neighbors | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 6 | IIS Neighbors | N | | 7 | Instance Identifier | Y |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 7 | Instance Identifier | Y | | 8 | Padding | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 8 | Padding | N | | 9 | LSP Entries | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 9 | LSP Entries | N | | 10 | Authentication | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 10 | Authentication | N | | 11 | ESN TLV | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 11 | ESN TLV | N | | 12 | Opt. Checksum | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 12 | Opt. Checksum | N | | 13 | Purge Originator Identification | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 13 | Purge Originator Identification | N | | 14 | LSPBufferSize | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 14 | LSPBufferSize | N | | 15 | Router-Fingerprint | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 15 | Router-Fingerprint | N | | 16 | Reverse Metric | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 16 | Reverse Metric | N | | 17 | IS-IS Area Node IDs TLV | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 17 | IS-IS Area Node IDs TLV | N | | 18 | IS-IS Flooding Path TLV | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 18 | IS-IS Flooding Path TLV | N | | 19 | IS-IS Flooding Request TLV | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 19 | IS-IS Flooding Request TLV | N | | 20 | Area Proxy | Y |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 20 | Area Proxy | Y | | 21 | Flooding Parameters TLV | Y |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 21 | Flooding Parameters TLV | Y | | 22 | Extended IS reachability | Y |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 22 | Extended IS reachability | Y | | 23 | IS Neighbor Attribute | Y |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 23 | IS Neighbor Attribute | Y | | 24 | IS Alias ID | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 24 | IS Alias ID | N | | 25 | L2 Bundle Member Attributes | Y |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 25 | L2 Bundle Member Attributes | Y | | 26 | Unassigned | |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 26 | Unassigned | | | 27 | SRv6 Locator | Y |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 27 | SRv6 Locator | Y | | 28-41 | Unassigned | |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 28-41 | Unassigned | | | 42 | DECnet Phase IV | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 42 | DECnet Phase IV | N | | 43-65 | Unassigned | |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 43-65 | Unassigned | | | 66 | Lucent Proprietary | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 66 | Lucent Proprietary | N | | 67-125 | Unassigned | |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 67-125 | Unassigned | | | 126 | IPv4 Algorithm Prefix Reachability | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 126 | IPv4 Algorithm Prefix Reachability TLV | N | | 127 | IPv6 Algorithm Prefix Reachability | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 127 | IPv6 Algorithm Prefix Reachability TLV | N | | 128 | IP Int. Reach | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 128 | IP Int. Reach | N | | 129 | Prot. Supported | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 129 | Prot. Supported | N | | 130 | IP Ext. Address | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 130 | IP Ext. Address | N | | 131 | IDRPI | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 131 | IDRPI | N | | 132 | IP Intf. Address | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 132 | IP Intf. Address | N | | 133 | Illegal | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 133 | Illegal | N | | 134 | Traffic Engineering router ID | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 134 | Traffic Engineering router ID | N | | 135 | Extended IP reachability | Y |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 135 | Extended IP reachability | Y | | 136 | Unassigned | |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 136 | Unassigned | | | 137 | Dynamic Name | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 137 | Dynamic Name | N | | 138 | GMPLS-SRLG | Y |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 138 | GMPLS-SRLG | Y | | 139 | IPv6 SRLG | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 139 | IPv6 SRLG | N | | 140 | IPv6 TE Router ID | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 140 | IPv6 TE Router ID | N | | 141 | inter-AS reachability information | Y |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 141 | inter-AS reachability information | Y | | 142 | GADDR-TLV | Y |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 142 | GADDR-TLV | Y | | 143 | MT-Port-Cap-TLV | Y |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 143 | MT-Port-Cap-TLV | Y | | 144 | MT-Capability TLV | Y |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 144 | MT-Capability TLV | Y | | 145 | TRILL Neighbor TLV | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 145 | TRILL Neighbor TLV | N | | 146 | Unassigned | |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 146 | Unassigned | | | 147 | MAC-RI TLV | Y |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 147 | MAC-RI TLV | Y | | 148 | BFD-Enabled TLV | Y |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 148 | BFD-Enabled TLV | Y | | 149 | Segment Identifier / Label Binding | Y |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 149 | Segment Identifier / Label Binding | Y | | 150 | Multi-Topology Segment Identifier | Y |
+-----------+----------------------------------------+----+ | | / Label Binding | |
| 150 | Multi-Topology Segment Identifier / | Y | +-----------+------------------------------------+----+
| | Label Binding | | | 151-160 | Unassigned | |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 151-160 | Unassigned | | | 161 | Flood Reflection | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 161 | Flood Reflection | N | | 162-175 | Unassigned | |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 162-175 | Unassigned | | | 176 | Nortel Proprietary | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 176 | Nortel Proprietary | N | | 177 | Nortel Proprietary | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 177 | Nortel Proprietary | N | | 178-210 | Unassigned | |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 178-210 | Unassigned | | | 211 | Restart TLV | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 211 | Restart TLV | N | | 212-221 | Unassigned | |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 212-221 | Unassigned | | | 222 | MT-ISN | Y |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 222 | MT-ISN | Y | | 223 | MT IS Neighbor Attribute | Y |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 223 | MT IS Neighbor Attribute | Y | | 224-228 | Unassigned | |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 224-228 | Unassigned | | | 229 | M-Topologies | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 229 | M-Topologies | N | | 230-231 | Unassigned | |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 230-231 | Unassigned | | | 232 | IPv6 Intf. Addr. | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 232 | IPv6 Intf. Addr. | N | | 233 | IPv6 Global Interface Address TLV | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 233 | IPv6 Global Interface Address TLV | N | | 234 | Unassigned | |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 234 | Unassigned | | | 235 | MT IP. Reach | Y |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 235 | MT IP. Reach | Y | | 236 | IPv6 IP. Reach | Y |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 236 | IPv6 IP. Reach | Y | | 237 | MT IPv6 IP. Reach | Y |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 237 | MT IPv6 IP. Reach | Y | | 238 | Application-Specific SRLG | Y |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 238 | Application-Specific SRLG | Y | | 239 | Unassigned | |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 239 | Unassigned | | | 240 | P2P 3-Way Adj. State | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 240 | P2P 3-Way Adj. State | N | | 241 | Unassigned | |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 241 | Unassigned | | | 242 | IS-IS Router CAPABILITY TLV | Y |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 242 | IS-IS Router CAPABILITY TLV | Y | | 243 | Scope Flooding Support | N |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 243 | Scope Flooding Support | N | | 244-250 | Unassigned | |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 244-250 | Unassigned | | | 251 | Generic Information | Y |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 251 | Generic Information | Y | | 252-65535 | Unassigned | |
+-----------+----------------------------------------+----+ +-----------+------------------------------------+----+
| 252-65535 | Unassigned | |
+-----------+----------------------------------------+----+
Table 1: IS-IS Top-Level TLV Codepoints Table 1: IS-IS Top-Level TLV Codepoints
9.2.2. MP-TLV for IS-IS Sub-TLVs for Reverse Metric TLV 9.2.2. MP-TLV for IS-IS Sub-TLVs for Reverse Metric TLV
(https://www.iana.org/assignments/isis-tlv-codepoints/isis-tlv-
codepoints.xhtml#tlv-16)
+========+============================+====+ +========+============================+====+
| Value | Name | MP | | Value | Name | MP |
+========+============================+====+ +========+============================+====+
| 0 | Reserved | | | 0 | Reserved | |
+--------+----------------------------+----+ +--------+----------------------------+----+
| 1-17 | Unassigned | | | 1-17 | Unassigned | |
+--------+----------------------------+----+ +--------+----------------------------+----+
| 18 | Traffic Engineering Metric | N | | 18 | Traffic Engineering Metric | N |
+--------+----------------------------+----+ +--------+----------------------------+----+
| 19-255 | Unassigned | | | 19-255 | Unassigned | |
+--------+----------------------------+----+ +--------+----------------------------+----+
Table 2: IS-IS Sub-TLVs for Reverse Table 2: IS-IS Sub-TLVs for Reverse
Metric TLV Metric TLV
9.2.3. MP-TLV for IS-IS Sub-TLVs for TLVs Advertising Neighbor 9.2.3. MP-TLV for IS-IS Sub-TLVs for TLVs Advertising Neighbor
Information Information
(https://www.iana.org/assignments/isis-tlv-codepoints/isis-tlv-
codepoints.xhtml#isis-tlv-codepoints-advertising-neighbor-
information)
+=========+===================================================+====+ +=========+===================================================+====+
| Value | Name | MP | | Value | Name | MP |
+=========+===================================================+====+ +=========+===================================================+====+
| 0-2 | Unassigned | | | 0-2 | Unassigned | |
+---------+---------------------------------------------------+----+ +---------+---------------------------------------------------+----+
| 3 | Administrative group (color) | N | | 3 | Administrative group (color) | N |
+---------+---------------------------------------------------+----+ +---------+---------------------------------------------------+----+
| 4 | Link Local/Remote Identifiers | N | | 4 | Link Local/Remote Identifiers | N |
+---------+---------------------------------------------------+----+ +---------+---------------------------------------------------+----+
| 5 | Unassigned | | | 5 | Unassigned | |
+---------+---------------------------------------------------+----+ +---------+---------------------------------------------------+----+
| 6 | IPv4 interface address | N | | 6 | IPv4 interface address | N |
skipping to change at page 18, line 37 skipping to change at line 806
| 250-254 | Reserved for Cisco-specific extensions | | | 250-254 | Reserved for Cisco-specific extensions | |
+---------+---------------------------------------------------+----+ +---------+---------------------------------------------------+----+
| 255 | Reserved for future expansion | | | 255 | Reserved for future expansion | |
+---------+---------------------------------------------------+----+ +---------+---------------------------------------------------+----+
Table 3: IS-IS Sub-TLVs for TLVs Advertising Neighbor Information Table 3: IS-IS Sub-TLVs for TLVs Advertising Neighbor Information
9.2.4. MP-TLV for IS-IS Sub-TLVs for TLVs Advertising Prefix 9.2.4. MP-TLV for IS-IS Sub-TLVs for TLVs Advertising Prefix
Reachability Reachability
(https://www.iana.org/assignments/isis-tlv-codepoints/isis-tlv-
codepoints.xhtml#isis-tlv-codepoints-advertising-prefix-reachability)
+========+=========================================+====+ +========+=========================================+====+
| Value | Name | MP | | Value | Name | MP |
+========+=========================================+====+ +========+=========================================+====+
| 0 | Unassigned | | | 0 | Unassigned | |
+--------+-----------------------------------------+----+ +--------+-----------------------------------------+----+
| 1 | 32-bit Administrative Tag Sub-TLV | Y | | 1 | 32-bit Administrative Tag Sub-TLV | Y |
+--------+-----------------------------------------+----+ +--------+-----------------------------------------+----+
| 2 | 64-bit Administrative Tag Sub-TLV | Y | | 2 | 64-bit Administrative Tag Sub-TLV | Y |
+--------+-----------------------------------------+----+ +--------+-----------------------------------------+----+
| 3 | Prefix Segment Identifier | N | | 3 | Prefix Segment Identifier | N |
+--------+-----------------------------------------+----+ +--------+-----------------------------------------+----+
| 4 | Prefix Attribute Flags | N | | 4 | Prefix Attribute Flags | N |
skipping to change at page 19, line 31 skipping to change at line 833
| 7-10 | Unassigned | | | 7-10 | Unassigned | |
+--------+-----------------------------------------+----+ +--------+-----------------------------------------+----+
| 11 | IPv4 Source Router ID | N | | 11 | IPv4 Source Router ID | N |
+--------+-----------------------------------------+----+ +--------+-----------------------------------------+----+
| 12 | IPv6 Source Router ID | N | | 12 | IPv6 Source Router ID | N |
+--------+-----------------------------------------+----+ +--------+-----------------------------------------+----+
| 13-31 | Unassigned | | | 13-31 | Unassigned | |
+--------+-----------------------------------------+----+ +--------+-----------------------------------------+----+
| 32 | BIER Info | Y | | 32 | BIER Info | Y |
+--------+-----------------------------------------+----+ +--------+-----------------------------------------+----+
| 32-255 | Unassigned | | | 33-255 | Unassigned | |
+--------+-----------------------------------------+----+ +--------+-----------------------------------------+----+
Table 4: IS-IS Sub-TLVs for TLVs Advertising Prefix Table 4: IS-IS Sub-TLVs for TLVs Advertising Prefix
Reachability Reachability
9.2.5. MP-TLV for IS-IS Sub-TLVs for MT-Capability TLV 9.2.5. MP-TLV for IS-IS Sub-TLVs for MT-Capability TLV
(https://www.iana.org/assignments/isis-tlv-codepoints/isis-tlv-
codepoints.xhtml#tlv-144)
+========+==============================+====+ +========+==============================+====+
| Value | Name | MP | | Value | Name | MP |
+========+==============================+====+ +========+==============================+====+
| 0 | Reserved | | | 0 | Reserved | |
+--------+------------------------------+----+ +--------+------------------------------+----+
| 1 | SPB-Inst | N | | 1 | SPB-Inst | N |
+--------+------------------------------+----+ +--------+------------------------------+----+
| 2 | SPB-I-OALG | Y | | 2 | SPB-I-OALG | Y |
+--------+------------------------------+----+ +--------+------------------------------+----+
| 3 | SPBM-SI | Y | | 3 | SPBM-SI | Y |
+--------+------------------------------+----+ +--------+------------------------------+----+
| 4 | SPBV-ADDR | Y | | 4 | SPBV-ADDR | Y |
skipping to change at page 21, line 7 skipping to change at line 901
+--------+------------------------------+----+ +--------+------------------------------+----+
| 26-254 | Unassigned | | | 26-254 | Unassigned | |
+--------+------------------------------+----+ +--------+------------------------------+----+
| 255 | Reserved | | | 255 | Reserved | |
+--------+------------------------------+----+ +--------+------------------------------+----+
Table 5: IS-IS Sub-TLVs for MT-Capability TLV Table 5: IS-IS Sub-TLVs for MT-Capability TLV
9.2.6. MP-TLV for IS-IS Sub-TLVs for IS-IS Router CAPABILITY TLV 9.2.6. MP-TLV for IS-IS Sub-TLVs for IS-IS Router CAPABILITY TLV
(https://www.iana.org/assignments/isis-tlv-codepoints/isis-tlv-
codepoints.xhtml#isis-tlv-codepoints-242)
+=========+====================================+====+ +=========+====================================+====+
| Value | Name | MP | | Value | Name | MP |
+=========+====================================+====+ +=========+====================================+====+
| 0 | Reserved | | | 0 | Reserved | |
+---------+------------------------------------+----+ +---------+------------------------------------+----+
| 1 | TE Node Capability Descriptor | N | | 1 | TE Node Capability Descriptor | N |
+---------+------------------------------------+----+ +---------+------------------------------------+----+
| 2 | Segment Routing Capability | N | | 2 | Segment Routing Capability | N |
+---------+------------------------------------+----+ +---------+------------------------------------+----+
| 3 | TE-MESH-GROUP TLV (IPv4) | Y | | 3 | TE-MESH-GROUP TLV (IPv4) | Y |
+---------+------------------------------------+----+ +---------+------------------------------------+----+
| 4 | TE-MESH-GROUP TLV (IPv6) | Y | | 4 | TE-MESH-GROUP TLV (IPv6) | Y |
skipping to change at page 22, line 38 skipping to change at line 978
| 161 | Flood Reflection Discovery | Y | | 161 | Flood Reflection Discovery | Y |
+---------+------------------------------------+----+ +---------+------------------------------------+----+
| 162-255 | Unassigned | | | 162-255 | Unassigned | |
+---------+------------------------------------+----+ +---------+------------------------------------+----+
Table 6: IS-IS Sub-TLVs for IS-IS Router Table 6: IS-IS Sub-TLVs for IS-IS Router
CAPABILITY TLV CAPABILITY TLV
9.2.7. IS-IS Sub-Sub-TLVs for SRv6 Capabilities Sub-TLV 9.2.7. IS-IS Sub-Sub-TLVs for SRv6 Capabilities Sub-TLV
(https://www.iana.org/assignments/isis-tlv-codepoints/isis-tlv-
codepoints.xhtml#isis-sub-sub-tlv-srv6-capability)
+=======+============+====+ +=======+============+====+
| Value | Name | MP | | Value | Name | MP |
+=======+============+====+ +=======+============+====+
| 0 | Reserved | | | 0 | Reserved | |
+-------+------------+----+ +-------+------------+----+
| 1-255 | Unassigned | | | 1-255 | Unassigned | |
+-------+------------+----+ +-------+------------+----+
Table 7: IS-IS Sub-Sub- Table 7: IS-IS Sub-Sub-
TLVs for SRv6 TLVs for SRv6
Capabilities Sub-TLV Capabilities Sub-TLV
9.2.8. MP-TLV IS-IS Sub-Sub-TLVs for BIER Info Sub-TLV 9.2.8. MP-TLV IS-IS Sub-Sub-TLVs for BIER Info Sub-TLV
(https://www.iana.org/assignments/isis-tlv-codepoints/isis-tlv-
codepoints.xhtml#bier-info-sub-tlv)
+=======+=========================+====+ +=======+=========================+====+
| Value | Name | MP | | Value | Name | MP |
+=======+=========================+====+ +=======+=========================+====+
| 0 | Unassigned | | | 0 | Unassigned | |
+-------+-------------------------+----+ +-------+-------------------------+----+
| 1 | BIER MPLS Encapsulation | N | | 1 | BIER MPLS Encapsulation | N |
+-------+-------------------------+----+ +-------+-------------------------+----+
| 2 | BIER PHP Request | N | | 2 | BIER PHP Request | N |
+-------+-------------------------+----+ +-------+-------------------------+----+
| 3-255 | Unassigned | | | 3-255 | Unassigned | |
+-------+-------------------------+----+ +-------+-------------------------+----+
Table 8: IS-IS Sub-Sub-TLVs for BIER Table 8: IS-IS Sub-Sub-TLVs for BIER
Info Sub-TLV Info Sub-TLV
9.2.9. MP-TLV for IS-IS Sub-TLVs for Segment Identifier/Label Binding 9.2.9. MP-TLV for IS-IS Sub-TLVs for Segment Identifier/Label Binding
TLVs TLVs
(https://www.iana.org/assignments/isis-tlv-codepoints/isis-tlv-
codepoints.xhtml#tlv-149-150)
+=======+===========================+====+ +=======+===========================+====+
| Value | Name | MP | | Value | Name | MP |
+=======+===========================+====+ +=======+===========================+====+
| 0 | Reserved | | | 0 | Reserved | |
+-------+---------------------------+----+ +-------+---------------------------+----+
| 1 | SID/Label | N | | 1 | SID/Label | N |
+-------+---------------------------+----+ +-------+---------------------------+----+
| 2 | Unassigned | | | 2 | Unassigned | |
+-------+---------------------------+----+ +-------+---------------------------+----+
| 3 | Prefix Segment Identifier | N | | 3 | Prefix Segment Identifier | N |
+-------+---------------------------+----+ +-------+---------------------------+----+
| 4-255 | Unassigned | | | 4-255 | Unassigned | |
+-------+---------------------------+----+ +-------+---------------------------+----+
Table 9: IS-IS Sub-TLVs for Segment Table 9: IS-IS Sub-TLVs for Segment
Identifier/Label Binding TLVs Identifier/Label Binding TLVs
9.2.10. MP-TLV for IS-IS Sub-Sub-TLV Codepoints for Application- 9.2.10. MP-TLV for IS-IS Sub-Sub-TLV Codepoints for Application-
Specific Link Attributes Specific Link Attributes
(https://www.iana.org/assignments/isis-tlv-codepoints/isis-tlv-
codepoints.xhtml#application-specific-link-attributes)
+========+====================================+====+ +========+====================================+====+
| Value | Name | MP | | Value | Name | MP |
+========+====================================+====+ +========+====================================+====+
| 0-2 | Unassigned | | | 0-2 | Unassigned | |
+--------+------------------------------------+----+ +--------+------------------------------------+----+
| 3 | Administrative group (color) | N | | 3 | Administrative group (color) | N |
+--------+------------------------------------+----+ +--------+------------------------------------+----+
| 4-8 | Unassigned | | | 4-8 | Unassigned | |
+--------+------------------------------------+----+ +--------+------------------------------------+----+
| 9 | Maximum link bandwidth | N | | 9 | Maximum link bandwidth | N |
+--------+------------------------------------+----+ +--------+------------------------------------+----+
| 10 | Maximum reservable link bandwidth | N | | 10 | Maximum reservable link bandwidth | N |
skipping to change at page 24, line 27 skipping to change at line 1053
| 11 | Unreserved bandwidth | N | | 11 | Unreserved bandwidth | N |
+--------+------------------------------------+----+ +--------+------------------------------------+----+
| 12-13 | Unassigned | | | 12-13 | Unassigned | |
+--------+------------------------------------+----+ +--------+------------------------------------+----+
| 14 | Extended Administrative Group | N | | 14 | Extended Administrative Group | N |
+--------+------------------------------------+----+ +--------+------------------------------------+----+
| 15-16 | Unassigned | | | 15-16 | Unassigned | |
+--------+------------------------------------+----+ +--------+------------------------------------+----+
| 17 | Generic Metric | Y | | 17 | Generic Metric | Y |
+--------+------------------------------------+----+ +--------+------------------------------------+----+
| 18 | TE Default Metric | N | | 18 | TE Default metric | N |
+--------+------------------------------------+----+ +--------+------------------------------------+----+
| 19-32 | Unassigned | | | 19-32 | Unassigned | |
+--------+------------------------------------+----+ +--------+------------------------------------+----+
| 33 | Unidirectional Link Delay | N | | 33 | Unidirectional Link Delay | N |
+--------+------------------------------------+----+ +--------+------------------------------------+----+
| 34 | Min/Max Unidirectional Link Delay | N | | 34 | Min/Max Unidirectional Link Delay | N |
+--------+------------------------------------+----+ +--------+------------------------------------+----+
| 35 | Unidirectional Delay Variation | N | | 35 | Unidirectional Delay Variation | N |
+--------+------------------------------------+----+ +--------+------------------------------------+----+
| 36 | Unidirectional Link Loss | N | | 36 | Unidirectional Link Loss | N |
skipping to change at page 25, line 7 skipping to change at line 1079
| 39 | Unidirectional Utilized Bandwidth | N | | 39 | Unidirectional Utilized Bandwidth | N |
+--------+------------------------------------+----+ +--------+------------------------------------+----+
| 40-255 | Unassigned | | | 40-255 | Unassigned | |
+--------+------------------------------------+----+ +--------+------------------------------------+----+
Table 10: IS-IS Sub-Sub-TLV Codepoints for Table 10: IS-IS Sub-Sub-TLV Codepoints for
Application-Specific Link Attributes Application-Specific Link Attributes
9.2.11. MP-TLV for IS-IS Sub-TLVs for Application-Specific SRLG TLV 9.2.11. MP-TLV for IS-IS Sub-TLVs for Application-Specific SRLG TLV
(https://www.iana.org/assignments/isis-tlv-codepoints/isis-tlv-
codepoints.xhtml#tlv-238)
+========+===============================+====+ +========+===============================+====+
| Value | Name | MP | | Value | Name | MP |
+========+===============================+====+ +========+===============================+====+
| 0-3 | Unassigned | | | 0-3 | Unassigned | |
+--------+-------------------------------+----+ +--------+-------------------------------+----+
| 4 | Link Local/Remote Identifiers | N | | 4 | Link Local/Remote Identifiers | N |
+--------+-------------------------------+----+ +--------+-------------------------------+----+
| 5 | Unassigned | | | 5 | Unassigned | |
+--------+-------------------------------+----+ +--------+-------------------------------+----+
| 6 | IPv4 interface address | N | | 6 | IPv4 interface address | N |
+--------+-------------------------------+----+ +--------+-------------------------------+----+
| 7 | Unassigned | | | 7 | Unassigned | |
skipping to change at page 25, line 39 skipping to change at line 1108
| 13 | IPv6 Neighbor Address | N | | 13 | IPv6 Neighbor Address | N |
+--------+-------------------------------+----+ +--------+-------------------------------+----+
| 14-255 | Unassigned | | | 14-255 | Unassigned | |
+--------+-------------------------------+----+ +--------+-------------------------------+----+
Table 11: IS-IS Sub-TLVs for Application- Table 11: IS-IS Sub-TLVs for Application-
Specific SRLG TLV Specific SRLG TLV
9.2.12. MP-TLV for IS-IS Sub-Sub-TLVs for SRv6 SID Sub-TLVs 9.2.12. MP-TLV for IS-IS Sub-Sub-TLVs for SRv6 SID Sub-TLVs
(https://www.iana.org/assignments/isis-tlv-codepoints/isis-tlv-
codepoints.xhtml#isis-sub-sub-tlvs-srv6-sid-sub-tlvs)
+=======+====================+====+ +=======+====================+====+
| Value | Name | MP | | Value | Name | MP |
+=======+====================+====+ +=======+====================+====+
| 0 | Reserved | | | 0 | Reserved | |
+-------+--------------------+----+ +-------+--------------------+----+
| 1 | SRv6 SID Structure | N | | 1 | SRv6 SID Structure | N |
+-------+--------------------+----+ +-------+--------------------+----+
| 2-255 | Unassigned | | | 2-255 | Unassigned | |
+-------+--------------------+----+ +-------+--------------------+----+
Table 12: IS-IS Sub-Sub-TLVs Table 12: IS-IS Sub-Sub-TLVs
for SRv6 SID Sub-TLVs for SRv6 SID Sub-TLVs
9.2.13. MP-TLV for IS-IS Sub-Sub-TLVs for Flexible Algorithm Definition 9.2.13. MP-TLV for IS-IS Sub-Sub-TLVs for Flexible Algorithm Definition
Sub-TLV Sub-TLV
(https://www.iana.org/assignments/isis-tlv-codepoints/isis-tlv-
codepoints.xhtml#isis-sub-sub-tlvs-flexible-algorithm-definition-sub-
tlv)
+========+============================================+====+ +========+============================================+====+
| Value | Name | MP | | Value | Name | MP |
+========+============================================+====+ +========+============================================+====+
| 0 | Reserved | | | 0 | Reserved | |
+--------+--------------------------------------------+----+ +--------+--------------------------------------------+----+
| 1 | Flexible Algorithm Exclude Admin Group | N | | 1 | Flexible Algorithm Exclude Admin Group | N |
+--------+--------------------------------------------+----+ +--------+--------------------------------------------+----+
| 2 | Flexible Algorithm Include-Any Admin Group | N | | 2 | Flexible Algorithm Include-Any Admin Group | N |
+--------+--------------------------------------------+----+ +--------+--------------------------------------------+----+
| 3 | Flexible Algorithm Include-All Admin Group | N | | 3 | Flexible Algorithm Include-All Admin Group | N |
+--------+--------------------------------------------+----+ +--------+--------------------------------------------+----+
| 4 | Flexible Algorithm Definition Flags | N | | 4 | Flexible Algorithm Definition Flags | N |
+--------+--------------------------------------------+----+ +--------+--------------------------------------------+----+
| 5 | Flexible Algorithm Exclude SRLG | N | | 5 | Flexible Algorithm Exclude SRLG | N |
+--------+--------------------------------------------+----+ +--------+--------------------------------------------+----+
| 6 | IS-IS Exclude Minimum Bandwidth | N | | 6 | IS-IS Exclude Minimum Bandwidth | N |
+--------+--------------------------------------------+----+ +--------+--------------------------------------------+----+
| 7 | IS-IS Exclude Maximum Delay | N | | 7 | IS-IS Exclude Maximum Delay | N |
+--------+--------------------------------------------+----+ +--------+--------------------------------------------+----+
| 8 | IS-IS Reference Bandwidth | N | | 8 | IS-IS Reference Bandwidth | N |
+--------+--------------------------------------------+----+ +--------+--------------------------------------------+----+
| 9 | IS-IS Threshold Metric | N | | 9 | IS-IS Bandwidth Metric | N |
+--------+--------------------------------------------+----+ +--------+--------------------------------------------+----+
| 10-255 | Unassigned | | | 10-255 | Unassigned | |
+--------+--------------------------------------------+----+ +--------+--------------------------------------------+----+
Table 13: IS-IS Sub-Sub-TLVs for Flexible Algorithm Table 13: IS-IS Sub-Sub-TLVs for Flexible Algorithm
Definition Sub-TLV Definition Sub-TLV
9.2.14. MP-TLV for IS-IS Sub-Sub-TLVs for Flood Reflection Discovery 9.2.14. MP-TLV for IS-IS Sub-Sub-TLVs for Flood Reflection Discovery
Sub-TLV Sub-TLV
(https://www.iana.org/assignments/isis-tlv-codepoints/isis-tlv-
codepoints.xhtml#isis-sub-sub-tlvs-flood-reflection-discovery-sub-
tlv)
+=========+================================+====+ +=========+================================+====+
| Value | Name | MP | | Value | Name | MP |
+=========+================================+====+ +=========+================================+====+
| 0-160 | Unassigned | | | 0-160 | Unassigned | |
+---------+--------------------------------+----+ +---------+--------------------------------+----+
| 161 | Flood Reflection Discovery | N | | 161 | Flood Reflection Discovery | N |
| | Tunnel Encapsulation Attribute | | | | Tunnel Encapsulation Attribute | |
+---------+--------------------------------+----+ +---------+--------------------------------+----+
| 162-255 | Unassigned | | | 162-255 | Unassigned | |
+---------+--------------------------------+----+ +---------+--------------------------------+----+
Table 14: IS-IS Sub-Sub-TLVs for Flood Table 14: IS-IS Sub-Sub-TLVs for Flood
skipping to change at page 27, line 37 skipping to change at line 1181
This document creates no new security issues for IS-IS. Additional This document creates no new security issues for IS-IS. Additional
instances of existing TLVs expose no new information. instances of existing TLVs expose no new information.
Note that support for MP-TLV may result in an implementation being Note that support for MP-TLV may result in an implementation being
more robust in handling unexpected occurrences of MP-TLV. more robust in handling unexpected occurrences of MP-TLV.
Security concerns for IS-IS are addressed in [ISO10589], [RFC5304], Security concerns for IS-IS are addressed in [ISO10589], [RFC5304],
and [RFC5310]. and [RFC5310].
11. Contributors 11. References
The following people gave a substantial contribution to the content
of this document and should be considered coauthors:
Chris Bowers
Email: cbowers107@gmail.com
12. References
12.1. Normative References 11.1. Normative References
[ISO10589] ISO, "Intermediate system to Intermediate system routing [ISO10589] ISO/IEC, "Information technology - Telecommunications and
information exchange protocol for use in conjunction with information exchange between systems - Intermediate System
the Protocol for providing the Connectionless-mode Network to Intermediate System intra-domain routeing information
Service (ISO 8473)", November 2002, <ISO/IEC 10589:2002>. exchange protocol for use in conjunction with the protocol
for providing the connectionless-mode network service (ISO
8473)", ISO/IEC 10589:2002, November 2002,
<https://www.iso.org/standard/30932.html>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997, DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>. <https://www.rfc-editor.org/info/rfc2119>.
[RFC5120] Przygienda, T., Shen, N., and N. Sheth, "M-ISIS: Multi [RFC5120] Przygienda, T., Shen, N., and N. Sheth, "M-ISIS: Multi
Topology (MT) Routing in Intermediate System to Topology (MT) Routing in Intermediate System to
Intermediate Systems (IS-ISs)", RFC 5120, Intermediate Systems (IS-ISs)", RFC 5120,
DOI 10.17487/RFC5120, February 2008, DOI 10.17487/RFC5120, February 2008,
skipping to change at page 29, line 28 skipping to change at line 1258
[RFC8918] Ginsberg, L., Wells, P., Li, T., Przygienda, T., and S. [RFC8918] Ginsberg, L., Wells, P., Li, T., Przygienda, T., and S.
Hegde, "Invalid TLV Handling in IS-IS", RFC 8918, Hegde, "Invalid TLV Handling in IS-IS", RFC 8918,
DOI 10.17487/RFC8918, September 2020, DOI 10.17487/RFC8918, September 2020,
<https://www.rfc-editor.org/info/rfc8918>. <https://www.rfc-editor.org/info/rfc8918>.
[RFC9479] Ginsberg, L., Psenak, P., Previdi, S., Henderickx, W., and [RFC9479] Ginsberg, L., Psenak, P., Previdi, S., Henderickx, W., and
J. Drake, "IS-IS Application-Specific Link Attributes", J. Drake, "IS-IS Application-Specific Link Attributes",
RFC 9479, DOI 10.17487/RFC9479, October 2023, RFC 9479, DOI 10.17487/RFC9479, October 2023,
<https://www.rfc-editor.org/info/rfc9479>. <https://www.rfc-editor.org/info/rfc9479>.
12.2. Informative References 11.2. Informative References
[I-D.ietf-lsr-isis-pics-yang] [PICS-YANG]
Qu, Y., Ginsberg, L., Przygienda, T., Decraene, B., and Y. Qu, Y., Ginsberg, L., Przygienda, T., Decraene, B., and Y.
Zhu, "YANG Model for IS-IS Protocol Implementation Zhu, "YANG Model for IS-IS Protocol Implementation
Conformance Statement (PICS)", Work in Progress, Internet- Conformance Statement (PICS)", Work in Progress, Internet-
Draft, draft-ietf-lsr-isis-pics-yang-01, 5 May 2025, Draft, draft-ietf-lsr-isis-pics-yang-01, 5 May 2025,
<https://datatracker.ietf.org/doc/html/draft-ietf-lsr- <https://datatracker.ietf.org/doc/html/draft-ietf-lsr-
isis-pics-yang-01>. isis-pics-yang-01>.
Contributors
The following individual made a substantial contribution to the
content of this document and should be considered a coauthor:
Chris Bowers
Email: cbowers107@gmail.com
Authors' Addresses Authors' Addresses
Parag Kaneriya Parag Kaneriya
Juniper Networks Juniper Networks
Elnath-Exora Business Park Survey Elnath-Exora Business Park Survey
Bangalore 560103 Bangalore 560103
Karnataka Karnataka
India India
Email: pkaneria@juniper.net Email: pkaneria@juniper.net
Tony Li Tony Li
Juniper Networks Juniper Networks
1133 Innovation Way 1133 Innovation Way
Sunnyvale, California 94089 Sunnyvale, California 94089
United States of America United States of America
Email: tony.li@tony.li Email: tony.li@tony.li
Antoni Przygienda Antoni Przygienda
Juniper Networks Juniper Networks
1133 Innovation Way 1133 Innovation Way
 End of changes. 97 change blocks. 
377 lines changed or deleted 335 lines changed or added

This html diff was produced by rfcdiff 1.48.