Internet Engineering Task Force (IETF) K. Talaulikar, Ed.

Internet Engineering Task Force (IETF) K. Talaulikar, Ed.
Request for Comments: 9356 P. Psenak
Updates: 9085 Cisco Systems
Category: Standards Track January 2023
ISSN: 2070-1721

Advertising Layer 2 Bundle Member Link Attributes in OSPF

Abstract

There are deployments where the Layer 3 (L3) interface on which OSPF
operates is a Layer 2 (L2) interface bundle. Existing OSPF
advertisements only support advertising link attributes of the L3
interface. If entities external to OSPF wish to control traffic
flows on the individual physical links that comprise the L2 interface
bundle, link attribute information for the bundle members is
required.

This document defines the protocol extensions for OSPF to advertise
the link attributes of L2 bundle members. The document also
specifies the advertisement of these OSPF extensions via the Border
Gateway Protocol - Link State (BGP-LS) and thereby updates RFC 9085.

Status of This Memo

This is an Internet Standards Track document.

This document is a product of the Internet Engineering Task Force
(IETF). It represents the consensus of the IETF community. It has
received public review and has been approved for publication by the
Internet Engineering Steering Group (IESG). Further information on
Internet Standards is available in Section 2 of RFC 7841.

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/rfc9356.

Copyright Notice

Copyright (c) 2023 IETF Trust and the persons identified as the
document authors. All rights reserved.

This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
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include Revised BSD License text as described in Section 4.e of the
Trust Legal Provisions and are provided without warranty as described
in the Revised BSD License.

Table of Contents

1. Introduction
1.1. Requirements Language
2. L2 Bundle Member Attributes
3. BGP-LS Advertisement
4. IANA Considerations
5. Operational Considerations
6. Security Considerations
7. References
7.1. Normative References
7.2. Informative References
Acknowledgements
Authors' Addresses

1. Introduction

There are deployments where the L3 interface on which an OSPF
adjacency is established is a L2 interface bundle, for instance, a
Link Aggregation Group (LAG) [IEEE802.1AX]. This reduces the number
of adjacencies that need to be maintained by the OSPF protocol in
cases where there are parallel links between the neighbors. Entities
external to OSPF such as Path Computation Elements (PCEs) [RFC4655]
may wish to control traffic flows on individual L2 member links of
the underlying bundle interface (e.g., LAG). To do so, link
attribute information for individual bundle members is required. The
protocol extensions defined in this document provide the means to
advertise this information.

This document defines sub-TLVs to advertise link attribute
information for each of the L2 bundle members that comprise the L3
interface on which OSPF operates. Similar capabilities were
introduced for IS-IS in [RFC8668].

[RFC8665] and [RFC8666] introduced the Adjacency Segment Identifier
(Adj-SID) link attribute for OSPFv2 and OSPFv3, respectively, which
can be used as an instruction to forward traffic over a specific link
[RFC8402]. This document enables the advertisement of the Adj-SIDs
using the same Adj-SID sub-TLV at the granularity level of each L2
bundle member link so that traffic may be steered over that specific
member link.

Note that the advertisements at the L2 bundle member link level
defined in this document are intended to be provided to entities
external to OSPF and do not alter or change the OSPF route
computation. The following items are intentionally not defined in
and are outside the scope of this document:

* What link attributes will be advertised. This is determined by
the needs of the external entities.

* A minimum or default set of link attributes.

* How these attributes are configured.

* How the advertisements are used.

* What impact the use of these advertisements may have on traffic
flow in the network.

* How the advertisements are passed to external entities.

BGP Link State (BGP-LS) [RFC7752] was extended for the advertisement
of L2 bundle members and their attributes in [RFC9085], which covered
only IS-IS. This document updates [RFC9085] by specifying the
advertisement from OSPF (refer to Section 3).

1.1. Requirements Language

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in
BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.

2. L2 Bundle Member Attributes

A new L2 Bundle Member Attributes sub-TLV is introduced to advertise
L2 bundle member attributes in both OSPFv2 and OSPFv3. In the case
of OSPFv2, this sub-TLV is an optional sub-TLV of the OSPFv2 Extended
Link TLV that is used to describe link attributes via the OSPFv2
Extended Link Opaque LSA (Link State Advertisement) [RFC7684]. In
the case of OSPFv3, this sub-TLV is an optional sub-TLV of the
Router-Link TLV of the OSPFv3 E-Router-LSA [RFC8362].

When the OSPF adjacency is associated with an L2 bundle interface,
this sub-TLV is used to advertise the underlying L2 bundle member
links along with their respective link attributes. The inclusion of
this information implies that the identified link is a member of the
L2 bundle associated with an OSPF L3 link and that the member link is
operationally up. Therefore, advertisements of member links MUST NOT
be done when the member link becomes operationally down or is no
longer a member of the identified L2 bundle.

The advertisement of the L2 Bundle Member Attributes sub-TLV may be
asymmetric for an OSPF link, depending on the underlying L2
connectivity, i.e., advertised by the router on only one end.

The L2 Bundle Member Attributes sub-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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| L2 Bundle Member Descriptor |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Member Link Attribute sub-TLVs (variable) //
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Figure 1: L2 Bundle Member Attributes Sub-TLV Format

Where:

Type: 24 for OSPFv2 and 29 for OSPFv3

Length: The total length (in octets) of the value portion of the TLV
including nested sub-TLVs.

L2 Bundle Member Descriptor: A 4-octet link-local identifier for the
member link. This identifier is described as "link local
identifier" in [RFC4202] and used as "Local Interface ID" in
[RFC8510].

Link attributes for L2 bundle member links are advertised as sub-TLVs
of the L2 Bundle Member Attributes sub-TLV.

In the case of OSPFv2, the L2 Bundle Member Attributes sub-TLV shares
the sub-TLV space of the Extended Link TLV, and the sub-TLVs of the
Extended Link TLV MAY be used to describe the attributes of the
member link. Table 1 lists sub-TLVs and their applicability for L2
bundle member links. The sub-TLVs that are not applicable MUST NOT
be used as sub-TLVs for the L2 Bundle Member Attributes sub-TLV.
Specifications that introduce new sub-TLVs of the Extended Link TLV
MUST indicate their applicability to the L2 Bundle Member Attributes
sub-TLV. Typically, attributes that have L3 semantics would not be
applicable, but L2 attributes would apply. An implementation MUST
ignore any sub-TLVs received that are not applicable in the context
of the L2 Bundle Member Attributes sub-TLV.

+=======+======================================+===============+
| Value | Description | Applicability |
+=======+======================================+===============+
| 1 | SID/Label | N |
+-------+--------------------------------------+---------------+
| 2 | Adj-SID | Y |
+-------+--------------------------------------+---------------+
| 3 | LAN Adj-SID/Label | Y |
+-------+--------------------------------------+---------------+
| 4 | Network-to-Router Metric | N |
+-------+--------------------------------------+---------------+
| 5 | RTM Capability | N |
+-------+--------------------------------------+---------------+
| 6 | OSPFv2 Link MSD | N |
+-------+--------------------------------------+---------------+
| 7 | Graceful-Link-Shutdown | N |
+-------+--------------------------------------+---------------+
| 8 | Remote IPv4 Address | N |
+-------+--------------------------------------+---------------+
| 9 | Local/Remote Interface ID | N |
+-------+--------------------------------------+---------------+
| 10 | Application-Specific Link Attributes | Y |
+-------+--------------------------------------+---------------+
| 11 | Shared Risk Link Group | Y |
+-------+--------------------------------------+---------------+
| 12 | Unidirectional Link Delay | Y |
+-------+--------------------------------------+---------------+
| 13 | Min/Max Unidirectional Link Delay | Y |
+-------+--------------------------------------+---------------+
| 14 | Unidirectional Delay Variation | Y |
+-------+--------------------------------------+---------------+
| 15 | Unidirectional Link Loss | Y |
+-------+--------------------------------------+---------------+
| 16 | Unidirectional Residual Bandwidth | Y |
+-------+--------------------------------------+---------------+
| 17 | Unidirectional Available Bandwidth | Y |
+-------+--------------------------------------+---------------+
| 18 | Unidirectional Utilized Bandwidth | Y |
+-------+--------------------------------------+---------------+
| 19 | Administrative Group | Y |
+-------+--------------------------------------+---------------+
| 20 | Extended Administrative Group | Y |
+-------+--------------------------------------+---------------+
| 22 | TE Metric | Y |
+-------+--------------------------------------+---------------+
| 23 | Maximum Link Bandwidth | Y |
+-------+--------------------------------------+---------------+
| 24 | L2 Bundle Member Attributes | N |
+-------+--------------------------------------+---------------+

Table 1: Applicability of OSPFv2 Link Attribute Sub-TLVs for
L2 Bundle Members

Applicability:

Y: This sub-TLV MAY appear in the L2 Bundle Member Attributes sub-
TLV.

N: This sub-TLV MUST NOT appear in the L2 Bundle Member Attributes
sub-TLV.

In the case of OSPFv3, the L2 Bundle Member Attributes sub-TLV shares
the sub-TLV space of the Router-Link TLV, and the sub-TLVs of the
Router-Link TLV MAY be used to describe the attributes of the member
link. Table 2 lists sub-TLVs that are applicable to the Router-Link
TLV and their applicability for L2 bundle member links. The sub-TLVs
that are not applicable MUST NOT be used as sub-TLVs for the L2
Bundle Member Attributes sub-TLV. Specifications that introduce new
sub-TLVs of the Router-Link TLV MUST indicate their applicability to
the L2 Bundle Member Attributes sub-TLV. An implementation MUST
ignore any sub-TLVs received that are not applicable in the context
of the L2 Bundle Member Attributes sub-TLV.

+=======+=========================================+===============+
| Value | Description | Applicability |
+=======+=========================================+===============+
| 1 | IPv6-Forwarding-Address | X |
+-------+-----------------------------------------+---------------+
| 2 | IPv4-Forwarding-Address | X |
+-------+-----------------------------------------+---------------+
| 3 | Route-Tag | X |
+-------+-----------------------------------------+---------------+
| 4 | Prefix SID | X |
+-------+-----------------------------------------+---------------+
| 5 | Adj-SID | Y |
+-------+-----------------------------------------+---------------+
| 6 | LAN Adj-SID | Y |
+-------+-----------------------------------------+---------------+
| 7 | SID/Label | N |
+-------+-----------------------------------------+---------------+
| 8 | Graceful-Link-Shutdown | N |
+-------+-----------------------------------------+---------------+
| 9 | OSPFv3 Link MSD | N |
+-------+-----------------------------------------+---------------+
| 11 | Application-Specific Link Attributes | Y |
+-------+-----------------------------------------+---------------+
| 12 | Shared Risk Link Group | Y |
+-------+-----------------------------------------+---------------+
| 13 | Unidirectional Link Delay | Y |
+-------+-----------------------------------------+---------------+
| 14 | Min/Max Unidirectional Link Delay | Y |
+-------+-----------------------------------------+---------------+
| 15 | Unidirectional Delay Variation | Y |
+-------+-----------------------------------------+---------------+
| 16 | Unidirectional Link Loss | Y |
+-------+-----------------------------------------+---------------+
| 17 | Unidirectional Residual Bandwidth | Y |
+-------+-----------------------------------------+---------------+
| 18 | Unidirectional Available Bandwidth | Y |
+-------+-----------------------------------------+---------------+
| 19 | Unidirectional Utilized Bandwidth | Y |
+-------+-----------------------------------------+---------------+
| 20 | Administrative Group | Y |
+-------+-----------------------------------------+---------------+
| 21 | Extended Administrative Group | Y |
+-------+-----------------------------------------+---------------+
| 22 | TE Metric | Y |
+-------+-----------------------------------------+---------------+
| 23 | Maximum Link Bandwidth | Y |
+-------+-----------------------------------------+---------------+
| 24 | Local Interface IPv6 Address | N |
+-------+-----------------------------------------+---------------+
| 25 | Remote Interface IPv6 Address | N |
+-------+-----------------------------------------+---------------+
| 26 | Flexible Algorithm Prefix Metric (FAPM) | X |
+-------+-----------------------------------------+---------------+
| 27 | Prefix Source OSPF Router-ID | X |
+-------+-----------------------------------------+---------------+
| 28 | Prefix Source Router Address | X |
+-------+-----------------------------------------+---------------+
| 29 | L2 Bundle Member Attributes | N |
+-------+-----------------------------------------+---------------+
| 33 | OSPF Flexible Algorithm ASBR Metric | X |
+-------+-----------------------------------------+---------------+

Table 2: Applicability of OSPFv3 Link Attribute Sub-TLVs for L2
Bundle Members

Applicability:

Y: This sub-TLV MAY appear in the L2 Bundle Member Attributes sub-
TLV.

N: This sub-TLV MUST NOT appear in the L2 Bundle Member Attributes
sub-TLV.

X: This is not a sub-TLV of the Router-Link TLV; it MUST NOT appear
in the L2 Bundle Member Attributes sub-TLV.

3. BGP-LS Advertisement

The BGP-LS extensions for the advertisement of L2 bundle members and
their attributes were specified in [RFC9085]. Using the OSPF L2
Bundle Member Attributes sub-TLV defined in this document, the L2
bundle member information can now be advertised from OSPF into BGP-LS
on the same lines as discussed for IS-IS in Section 2.2.3 of
[RFC9085].

4. IANA Considerations

IANA has allocated the following code point in the "OSPFv2 Extended
Link TLV Sub-TLVs" subregistry under the "Open Shortest Path First v2
(OSPFv2) Parameters" registry:

Value: 24

Designation: L2 Bundle Member Attributes

IANA has allocated the following code point in the "OSPFv3 Extended-
LSA Sub-TLVs" subregistry under the "Open Shortest Path First v3
(OSPFv3) Parameters" registry:

Value: 29

Description: L2 Bundle Member Attributes

IANA has also introduced a column titled "L2BM" in the "OSPFv2
Extended Link TLV Sub-TLVs" registry. The "L2BM" column indicates
applicability to the L2 Bundle Attributes Member sub-TLV. The
initial allocations (Y/N) for this column are indicated in Table 1.
The following explanatory note has been added to the registry:

| The "L2BM" column indicates applicability to the L2 Bundle
| Attributes Member sub-TLV. The options for the "L2BM" column are:
|
| Y - This sub-TLV MAY appear in the L2 Bundle Member Attributes
| sub-TLV.
|
| N - This sub-TLV MUST NOT appear in the L2 Bundle Member
| Attributes sub-TLV.

Similarly, IANA has introduced a column titled "L2BM" in the "OSPFv3
Extended-LSA Sub-TLVs" registry. The "L2BM" column indicates
applicability to the L2 Bundle Attributes Member sub-TLV. The
initial allocations (Y/N/X) for this column are indicated in Table 2.
The following explanatory note has been added to the registry:

| The "L2BM" column indicates applicability to the L2 Bundle
| Attributes Member sub-TLV. The options for the "L2BM" column are:
|
| Y - This sub-TLV MAY appear in the L2 Bundle Member Attributes
| sub-TLV.
|
| N - This sub-TLV MUST NOT appear in the L2 Bundle Member
| Attributes sub-TLV.
|
| X - This is not a sub-TLV of the Router-Link TLV; it MUST NOT
| appear in the L2 Bundle Member Attributes sub-TLV.

Future allocations in these two registries are required to indicate
the applicability of the introduced sub-TLV to the L2 Bundle Member
Attributes sub-TLV. IANA has added this document as a reference for
both registries.

5. Operational Considerations

Implementations MUST NOT enable the advertisement of L2 bundle member
links and their attributes in OSPF LSAs by default and MUST provide a
configuration option to enable their advertisement on specific links.

[RFC9129] specifies the base YANG data model for OSPF. The required
configuration and operational elements for this feature are expected
to be introduced as augmentation to this base YANG data model for
OSPF.

6. Security Considerations

The OSPF protocol has supported the advertisement of link attribute
information, including link identifiers, for many years. The
advertisements defined in this document are identical to the existing
advertisements defined in [RFC3630], [RFC4203], [RFC5329], [RFC7471],
[RFC8665], and [RFC8666], but they are associated with L2 links that
are part of a bundle interface on which the OSPF protocol operates.
Therefore, the security considerations of these documents are
applicable, and there are no new security issues introduced by the
extensions in this document.

As always, if the protocol is used in an environment where
unauthorized access to the physical links on which OSPF packets are
sent occurs, then attacks are possible. The use of authentication as
defined in [RFC5709], [RFC7474], [RFC4552], and [RFC7166] is
recommended for preventing such attacks.

7. References

7.1. Normative References

[IEEE802.1AX]
IEEE, "IEEE Standard for Local and Metropolitan Area
Networks--Link Aggregation", IEEE Std 802.1AX,
DOI 10.1109/IEEESTD.2020.9105034, May 2020,
<https://doi.org/10.1109/IEEESTD.2020.9105034>.

[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.

[RFC4202] Kompella, K., Ed. and Y. Rekhter, Ed., "Routing Extensions
in Support of Generalized Multi-Protocol Label Switching
(GMPLS)", RFC 4202, DOI 10.17487/RFC4202, October 2005,
<https://www.rfc-editor.org/info/rfc4202>.

[RFC7684] Psenak, P., Gredler, H., Shakir, R., Henderickx, W.,
Tantsura, J., and A. Lindem, "OSPFv2 Prefix/Link Attribute
Advertisement", RFC 7684, DOI 10.17487/RFC7684, November
2015, <https://www.rfc-editor.org/info/rfc7684>.

[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.

[RFC8362] Lindem, A., Roy, A., Goethals, D., Reddy Vallem, V., and
F. Baker, "OSPFv3 Link State Advertisement (LSA)
Extensibility", RFC 8362, DOI 10.17487/RFC8362, April
2018, <https://www.rfc-editor.org/info/rfc8362>.

[RFC8665] Psenak, P., Ed., Previdi, S., Ed., Filsfils, C., Gredler,
H., Shakir, R., Henderickx, W., and J. Tantsura, "OSPF
Extensions for Segment Routing", RFC 8665,
DOI 10.17487/RFC8665, December 2019,
<https://www.rfc-editor.org/info/rfc8665>.

[RFC8666] Psenak, P., Ed. and S. Previdi, Ed., "OSPFv3 Extensions
for Segment Routing", RFC 8666, DOI 10.17487/RFC8666,
December 2019, <https://www.rfc-editor.org/info/rfc8666>.

[RFC9085] Previdi, S., Talaulikar, K., Ed., Filsfils, C., Gredler,
H., and M. Chen, "Border Gateway Protocol - Link State
(BGP-LS) Extensions for Segment Routing", RFC 9085,
DOI 10.17487/RFC9085, August 2021,
<https://www.rfc-editor.org/info/rfc9085>.

7.2. Informative References

[RFC3630] Katz, D., Kompella, K., and D. Yeung, "Traffic Engineering
(TE) Extensions to OSPF Version 2", RFC 3630,
DOI 10.17487/RFC3630, September 2003,
<https://www.rfc-editor.org/info/rfc3630>.

[RFC4203] Kompella, K., Ed. and Y. Rekhter, Ed., "OSPF Extensions in
Support of Generalized Multi-Protocol Label Switching
(GMPLS)", RFC 4203, DOI 10.17487/RFC4203, October 2005,
<https://www.rfc-editor.org/info/rfc4203>.

[RFC4552] Gupta, M. and N. Melam, "Authentication/Confidentiality
for OSPFv3", RFC 4552, DOI 10.17487/RFC4552, June 2006,
<https://www.rfc-editor.org/info/rfc4552>.

[RFC4655] Farrel, A., Vasseur, J.-P., and J. Ash, "A Path
Computation Element (PCE)-Based Architecture", RFC 4655,
DOI 10.17487/RFC4655, August 2006,
<https://www.rfc-editor.org/info/rfc4655>.

[RFC5329] Ishiguro, K., Manral, V., Davey, A., and A. Lindem, Ed.,
"Traffic Engineering Extensions to OSPF Version 3",
RFC 5329, DOI 10.17487/RFC5329, September 2008,
<https://www.rfc-editor.org/info/rfc5329>.

[RFC5709] Bhatia, M., Manral, V., Fanto, M., White, R., Barnes, M.,
Li, T., and R. Atkinson, "OSPFv2 HMAC-SHA Cryptographic
Authentication", RFC 5709, DOI 10.17487/RFC5709, October
2009, <https://www.rfc-editor.org/info/rfc5709>.

[RFC7166] Bhatia, M., Manral, V., and A. Lindem, "Supporting
Authentication Trailer for OSPFv3", RFC 7166,
DOI 10.17487/RFC7166, March 2014,
<https://www.rfc-editor.org/info/rfc7166>.

[RFC7471] Giacalone, S., Ward, D., Drake, J., Atlas, A., and S.
Previdi, "OSPF Traffic Engineering (TE) Metric
Extensions", RFC 7471, DOI 10.17487/RFC7471, March 2015,
<https://www.rfc-editor.org/info/rfc7471>.

[RFC7474] Bhatia, M., Hartman, S., Zhang, D., and A. Lindem, Ed.,
"Security Extension for OSPFv2 When Using Manual Key
Management", RFC 7474, DOI 10.17487/RFC7474, April 2015,
<https://www.rfc-editor.org/info/rfc7474>.

[RFC7752] Gredler, H., Ed., Medved, J., Previdi, S., Farrel, A., and
S. Ray, "North-Bound Distribution of Link-State and
Traffic Engineering (TE) Information Using BGP", RFC 7752,
DOI 10.17487/RFC7752, March 2016,
<https://www.rfc-editor.org/info/rfc7752>.

[RFC8402] Filsfils, C., Ed., Previdi, S., Ed., Ginsberg, L.,
Decraene, B., Litkowski, S., and R. Shakir, "Segment
Routing Architecture", RFC 8402, DOI 10.17487/RFC8402,
July 2018, <https://www.rfc-editor.org/info/rfc8402>.

[RFC8510] Psenak, P., Ed., Talaulikar, K., Henderickx, W., and P.
Pillay-Esnault, "OSPF Link-Local Signaling (LLS)
Extensions for Local Interface ID Advertisement",
RFC 8510, DOI 10.17487/RFC8510, January 2019,
<https://www.rfc-editor.org/info/rfc8510>.

[RFC8668] Ginsberg, L., Ed., Bashandy, A., Filsfils, C., Nanduri,
M., and E. Aries, "Advertising Layer 2 Bundle Member Link
Attributes in IS-IS", RFC 8668, DOI 10.17487/RFC8668,
December 2019, <https://www.rfc-editor.org/info/rfc8668>.

[RFC9129] Yeung, D., Qu, Y., Zhang, Z., Chen, I., and A. Lindem,
"YANG Data Model for the OSPF Protocol", RFC 9129,
DOI 10.17487/RFC9129, October 2022,
<https://www.rfc-editor.org/info/rfc9129>.

Acknowledgements

This document leverages similar work done for IS-IS, and the authors
of this document would like to acknowledge the contributions of the
authors of [RFC8668].

The authors would like to thank Anoop Ghanwani, Paul Kyzivat, Dan
Romascanu, and Russ Mundy for their review and feedback on this
document. The authors would also like to thank Acee Lindem for his
detailed shepherd review of this document. The authors would also
like to thank John Scudder for his AD review and the discussion
related to the applicability of TLVs/sub-TLVs to the L2 Bundle Member
Attributes sub-TLV.

Authors' Addresses

Ketan Talaulikar (editor)
Cisco Systems
India
Email: [email protected]

Peter Psenak
Cisco Systems
Apollo Business Center
Mlynske nivy 43
821 09 Bratislava
Slovakia
Email: [email protected]