BGP Router Capabilities Attribute
draft-ietf-idr-entropy-label-02
The information below is for an old version of the document.
| Document | Type |
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| Authors | Bruno Decraene , John Scudder , Wim Henderickx , Kireeti Kompella , Satya Mohanty , Jim Uttaro , Bin Wen | ||
| Last updated | 2022-12-21 | ||
| Replaces | draft-scudder-idr-entropy-label, draft-ietf-idr-next-hop-capability | ||
| RFC stream | Internet Engineering Task Force (IETF) | ||
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| Stream | WG state | WG Document | |
| Document shepherd | Susan Hares | ||
| Shepherd write-up | Show Last changed 2022-10-12 | ||
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draft-ietf-idr-entropy-label-02
Internet Engineering Task Force B. Decraene, Ed.
Internet-Draft Orange
Updates: 6790, 7447 (if approved) J. G. Scudder, Ed.
Intended status: Standards Track Juniper Networks
Expires: 24 June 2023 W. Henderickx
Nokia
K. Kompella
Juniper Networks
S. Mohanty
Cisco Systems
J. Uttaro
AT&T
B. Wen
Comcast
21 December 2022
BGP Router Capabilities Attribute
draft-ietf-idr-entropy-label-02
Abstract
RFC 5492 allows a BGP speaker to advertise its capabilities to its
peer. When a route is propagated beyond the immediate peer, it is
useful to allow certain capabilities to be conveyed further. In
particular, it may be useful to advertise forwarding plane features.
This specification defines a new BGP transitive attribute to carry
such capability information, the "Router Capabilities Attribute," or
RCA.
This specification also defines an RCA capability that can be used to
advertise the ability to process the MPLS Entropy Label as an egress
LSR for all NLRI advertised in the BGP UPDATE. It updates RFC 6790
and RFC 7447 concerning this BGP signaling.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
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/.
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Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on 24 June 2023.
Copyright Notice
Copyright (c) 2022 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 to this document. Code Components
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provided without warranty as described in the Revised BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Requirements Language . . . . . . . . . . . . . . . . . . 3
2. BGP Router Capabilities Attribute . . . . . . . . . . . . . . 3
2.1. Encoding . . . . . . . . . . . . . . . . . . . . . . . . 4
2.2. Sending the RCA . . . . . . . . . . . . . . . . . . . . . 5
2.3. Receiving the RCA . . . . . . . . . . . . . . . . . . . . 6
2.4. Attribute Error Handling . . . . . . . . . . . . . . . . 7
2.5. Network Operation Considerations . . . . . . . . . . . . 7
3. Entropy Label Capability (ELCv3) . . . . . . . . . . . . . . 7
3.1. Encoding . . . . . . . . . . . . . . . . . . . . . . . . 8
3.2. Sending the ELCv3 . . . . . . . . . . . . . . . . . . . . 8
3.3. Receiving the ELCv3 . . . . . . . . . . . . . . . . . . . 8
3.4. ELCv3 Error Handling . . . . . . . . . . . . . . . . . . 9
4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 9
5. Security Considerations . . . . . . . . . . . . . . . . . . . 10
5.1. Considerations for the RCA . . . . . . . . . . . . . . . 10
5.2. Considerations for the ELCv3 Capability . . . . . . . . . 10
6. References . . . . . . . . . . . . . . . . . . . . . . . . . 10
6.1. Normative References . . . . . . . . . . . . . . . . . . 10
6.2. Informative References . . . . . . . . . . . . . . . . . 11
Appendix A. Other Means of Signaling EL Capability . . . . . . . 12
Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 12
Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 13
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1. Introduction
[RFC5492] allows a BGP speaker to advertise its capabilities to its
peer. When a route is propagated beyond the immediate peer, it is
useful to allow certain capabilities to be conveyed further. In
particular, it may be useful to advertise forwarding plane features.
This specification defines a new BGP optional transitive attribute to
carry such capability information, the "Router Capabilities
Attribute", or RCA. (This somewhat ponderous name is regrettable but
is needed in order to be descriptive while still distinguishing it
from RFC 5492 BGP Capabilities.)
Since the RCA is intended chiefly for conveying information about
forwarding plane features, it needs to be regenerated whenever the
BGP route's next hop is changed. Since owing to the properties of
BGP transitive attributes this can't be guaranteed (an intermediate
router that doesn't implement this specification would be expected to
propagate the RCA as opaque data), the RCA identifies itself with the
next hop of its originator. If the RCA passes through a router that
changes the next hop without regenerating the RCA, they will fail to
match when later examined, and the recipient can act accordingly.
This scheme allows RCA support to be introduced into a network
incrementally. Complete details are provided in Section 2.
This specification also defines an RCA to advertise the ability to
process the MPLS Entropy Label as an egress LSR for all NLRI
advertised in the BGP UPDATE. It updates [RFC6790] and [RFC7447]
with regard to this BGP signaling, this is further discussed in
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. BGP Router Capabilities Attribute
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2.1. Encoding
The BGP Router Capabilities attribute (RCA attribute, or just RCA) is
an optional, transitive BGP path attribute with type code 39. The
RCA has as its data a network layer address, representing the next
hop of the route the RCA accompanies. The RCA signals potentially
useful optimizations, so it is desirable to make it transitive; the
next hop data is to ensure correctness if it traverses BGP speakers
that do not understand the RCA.
The Attribute Data field of the RCA attribute is encoded as a header
portion that identifies the originator of the attribute, followed by
one or more capability TLVs.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Address Family Identifier | SAFI | Next Hop Len |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ Network Address of Next Hop (variable) ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ Capability TLVs (variable) ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1: RCA Format
The meanings of the header fields (Address Family Identifier, SAFI or
Subsequent Address Family Identifier, Length of Next Hop, and Network
Address of Next Hop) are as given in Section 3 of [RFC4760].
In turn, each Capability is a triple (Capability Code, Capability
Length, Capability Value):
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Capability Code | Capability Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ Capability Value (variable) ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2: Capability TLV Format
Capability Code: a two-octet unsigned binary integer that indicates
the type of Capability advertised and unambiguously identifies an
individual capability.
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Capability Length: a two-octet unsigned binary integer that indicates
the length, in octets, of the Capability Value field. A length of 0
indicates that no Capability Value field is present.
Capability Value: a variable-length field. It is interpreted
according to the value of the Capability Code.
A BGP speaker MUST NOT include more than one instance of a capability
with the same Capability Code, Capability Length, and Capability
Value. Note, however, that processing multiple instances of such a
capability does not require special handling, as additional instances
do not change the meaning of the announced capability; thus, a BGP
speaker MUST be prepared to accept such multiple instances.
BGP speakers MAY include more than one instance of a capability (as
identified by the Capability Code) with different Capability Value
and either the same or different Capability Length. Processing of
these capability instances is specific to the Capability Code and
MUST be described in the document introducing the new capability.
Capability TLVs MUST be placed in the RCA in increasing order of
Capability Code. (In the event of multiple instances of a capability
with the same Capability Code as discussed above, no further sorting
order is defined here.) Although the major sorting order is
mandated, an implementation MAY elect to be prepared to consume
capabilities in any order, for robustness reasons.
2.2. Sending the RCA
Suppose a BGP speaker S has a route R it wishes to advertise with
next hop N to its peer.
If S is originating R into BGP, it MAY include an RCA attribute with
it, that carries capability TLVs that describe aspects of R. S MUST
set the header portion of the RCA to be equal to N, using the
encoding given above.
If S has received R from some other BGP speaker, two possibilities
exist. First, S could be propagating R without changing N. In that
case, S need take no special action, it SHOULD simply propagate the
RCA unchanged unless specifically configured otherwise. Indeed, we
observe that this is no different from the default action a BGP
speaker takes with an unrecognized optional transitive attribute --
it is treated as opaque data and propagated.
Second, S could be changing R in some way, and in particular, it
could be changing N. If S has changed N it MUST NOT propagate the
RCA unchanged. It MAY include a newly-constructed RCA attribute with
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R, constructed as described above in the "originating R into BGP"
case. Any given capability TLV carried by the newly-constructed RCA
attribute might use information from the received RCA attribute as
input to its construction; the details of this are specific to the
definition of each capability.
The RCA MAY be sent by default to IBGP peers. It MUST NOT be sent by
default to peers not under the administrative control of the local
network administrator (so, generally, to EBGP peers).
We note that due to the nature of BGP optional transitive path
attributes, any BGP speaker that does not implement this
specification will propagate the RCA, the requirements of this
section notwithstanding. Such a speaker will not update the RCA,
however.
2.3. Receiving the RCA
By default, the RCA MUST NOT be accepted from peers not under the
administrative control of the local network administrator (so,
generally, from EBGP peers); if received it MUST be discarded without
further processing, except that the contents MAY be logged. An
implementation MAY enable RCA processing by default from peers under
the administrative control of the local network administrator (so,
generally, from IBGP peers). An implementation SHOULD provide the
ability to modify these default settings by configuration.
When a BGP speaker receives a BGP route that includes the RCA, it
MUST compare the address given in the header portion of the RCA to
the next hop of the BGP route. If the two are equal, the RCA may be
further processed. If the two are not equal, it means some
intermediate BGP speaker that handled the route in transit both does
not support RCA, and changed the next hop of the route. In this
case, the contents of the RCA cannot be used, and the RCA MUST be
discarded without further processing, except that the contents MAY be
logged.
A BGP speaker receiving a Capability Code that it supports behaves as
defined in the document defining the Capability Code. A BGP speaker
receiving a Capability Code that it does not support MUST ignore that
Capability Code. In particular, it MUST NOT be handled as an error.
The presence of a Capability SHOULD NOT influence route selection or
route preference, unless tunneling is used to reach the BGP next hop
or the selected route has been learned from External BGP (that is,
the next hop is in a different Autonomous System). Indeed, it is in
general impossible for a node to know that all BGP routers of the
Autonomous System (AS) will understand a given capability, and if
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different routers within an AS were to use a different preference for
a route, forwarding loops could result unless tunneling is used to
reach the BGP next hop.
2.4. Attribute Error Handling
An RCA is considered malformed if the length of the attribute is
inconsistent with the lengths of the contained capability TLVs.
A BGP UPDATE message with a malformed RCA SHALL be handled using the
approach of "attribute discard" defined in [RFC7606].
Unknown Capability Codes MUST NOT be considered to be an error.
A document that specifies a new RCA Capability should provide
specifics regarding what constitutes an error for that RCA
Capability.
If a capability TLV is malformed, that capability TLV MUST be ignored
and removed. Other capability TLVs MUST be processed as usual.
2.5. Network Operation Considerations
In the corner case where multiple nodes use the same IP address as
their BGP next hop, such as with anycast nodes as described in
[RFC4786], a BGP speaker MUST NOT advertise a given capability unless
all nodes sharing this same IP address support this capability. The
network operator operating those anycast nodes is responsible for
ensuring that an anycast node does not advertise a capability not
supported by all nodes sharing this anycast address. The means for
accomplishing this are beyond the scope of this document.
3. Entropy Label Capability (ELCv3)
When BGP [RFC4271] is used for distributing labeled Network Layer
Reachability Information (NLRI) as described in, for example,
[RFC8277], the route may include the ELCv3 as part of the RCA. The
inclusion of this capability with a route indicates that the egress
of the associated Label Switched Path (LSP) can process entropy
labels as an egress Label Switched Router (LSR) for that route -- see
Section 4.2 of [RFC6790]. Below, we refer to this for brevity as
being "EL-capable."
For historical reasons, this capability is referred to as "ELCv3", to
distinguish it from the prior Entropy Label Capability (ELC) defined
in [RFC6790] and deprecated in [RFC7447], and the ELCv2 described in
[I-D.scudder-bgp-entropy-label].
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3.1. Encoding
The ELCv3 has capability code 1, capability length 0, and carries no
value:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Capability Code = 1 | Capability Length = 0 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 3: ELCv3 TLV Format
3.2. Sending the ELCv3
When a BGP speaker S has a route R it wishes to advertise with next
hop N to its peer, it MUST NOT include the ELCv3 capability except if
it knows that the egress of the associated LSP L is EL-capable.
Specifically, this will be true if S:
* Is itself the egress, and knows itself to be EL-capable, or
* Is re-advertising a BGP route it received with a valid ELCv3
capability, and is not changing the value of N, or
* Is re-advertising a BGP route it received with a valid ELCv3
capability, and is changing the value of N, and knows (for
example, through configuration) that the router represented by N
is either the LSP egress and is EL-capable, or that it will simply
swap labels without popping the entire label stack and processing
the label below, as with a transit LSR, or
* Is redistributing a route learned from another protocol, and that
other protocol conveyed the knowledge that the egress of L was EL-
capable (for example, this might be known through the LDP ELC TLV,
Section 5.1 of [RFC6790]).
The ELCv3 MAY be advertised with routes that are labeled, such as
those using SAFI 4 [RFC8277]. It MUST NOT be advertised with
unlabeled routes.
3.3. Receiving the ELCv3
(Below, we assume that "includes the ELCv3" implies that the
containing RCA has passed the checks specified in Section 2.3. If it
had not passed, then the RCA would have been discarded and the ELCv3
would be deemed not to have been included.)
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When a BGP speaker receives an unlabeled route that includes the
ELCv3, it MUST discard the ELCv3.
When a BGP speaker receives a labeled route that includes the ELCv3,
that indicates the LSP supports entropy labels, which implies that
the receiving BGP speaker, if acting as ingress, MAY insert an
entropy label as per Section 4.2 of [RFC6790].
3.4. ELCv3 Error Handling
The ELCv3 is considered malformed and must be disregarded if its
length is other than zero.
4. IANA Considerations
IANA has made a temporary allocation in the BGP Path Attributes
registry of the Border Gateway Protocol (BGP) Parameters group. IANA
is requested to make this allocation permanent.
+=======+===============================+============+
| Value | Code | Reference |
+=======+===============================+============+
| 39 | BGP Router Capabilities (RCA) | (this doc) |
+-------+-------------------------------+------------+
Table 1
IANA is requested to create a new registry called "BGP Router
Capability Codes" within the Border Gateway Protocol (BGP) Parameters
group. The registry's allocation policy is First Come, First Served.
It is seeded with the following values:
+===============+==================+============+===================+
| Value | Description | Reference | Change Controller |
+===============+==================+============+===================+
| 0 | reserved | (this doc) | IETF |
+---------------+------------------+------------+-------------------+
| 1 | ELCv3 | (this doc) | IETF |
+---------------+------------------+------------+-------------------+
| 65500 - | reserved for | (this doc) | IETF |
| 65534 | experimental use | | |
+---------------+------------------+------------+-------------------+
| 65535 | reserved | (this doc) | IETF |
+---------------+------------------+------------+-------------------+
Table 2
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5. Security Considerations
5.1. Considerations for the RCA
The header portion of the RCA contains the next hop the attribute's
originator included when sending it. This will typically be an IP
address of the router in question. This may be an infrastructure
address the network operator does not intend to announce beyond the
border of its Autonomous System, and it may even be considered in
some weak sense, confidential information. Although the desired
operation of the protocol is for the attribute's propagation scope to
be limited to the network operator's own Autonomous System, this
can't be guaranteed in all cases -- if a border router doesn't
implement this specification, the attribute, like all BGP optional
transitive attributes, will propagate to neighboring Autonomous
Systems. So, sometimes this information could leak beyond its
intended scope. (Note that it will only propagate as far as the
first router that does support this specification, at which point it
will be discarded per Section 2.3.)
If the attribute leaks beyond its intended scope, capabilities within
it would potentially be exposed. Specifications for individual
capabilities should consider the consequences of such unintended
exposure.
5.2. Considerations for the ELCv3 Capability
Insertion of an ELCv3 by an attacker could cause forwarding to fail.
Deletion of an ELCv3 by an attacker could cause one path in the
network to be overutilized and another to be underutilized. However,
we note that an attacker able to accomplish either of these (below,
an "on-path attacker") could equally insert or remove any other BGP
path attribute or message. The former attack described above denies
service for a given route, which can be accomplished by an on-path
attacker in any number of ways even absent ELCv3. The latter attack
defeats an optimization but nothing more; it seems dubious that an
attacker would go to the trouble of doing so rather than launching
some more damaging attack.
6. References
6.1. Normative References
[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>.
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[RFC4271] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A
Border Gateway Protocol 4 (BGP-4)", RFC 4271,
DOI 10.17487/RFC4271, January 2006,
<https://www.rfc-editor.org/info/rfc4271>.
[RFC4760] Bates, T., Chandra, R., Katz, D., and Y. Rekhter,
"Multiprotocol Extensions for BGP-4", RFC 4760,
DOI 10.17487/RFC4760, January 2007,
<https://www.rfc-editor.org/info/rfc4760>.
[RFC6790] Kompella, K., Drake, J., Amante, S., Henderickx, W., and
L. Yong, "The Use of Entropy Labels in MPLS Forwarding",
RFC 6790, DOI 10.17487/RFC6790, November 2012,
<https://www.rfc-editor.org/info/rfc6790>.
[RFC7447] Scudder, J. and K. Kompella, "Deprecation of BGP Entropy
Label Capability Attribute", RFC 7447,
DOI 10.17487/RFC7447, February 2015,
<https://www.rfc-editor.org/info/rfc7447>.
[RFC7606] Chen, E., Ed., Scudder, J., Ed., Mohapatra, P., and K.
Patel, "Revised Error Handling for BGP UPDATE Messages",
RFC 7606, DOI 10.17487/RFC7606, August 2015,
<https://www.rfc-editor.org/info/rfc7606>.
[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>.
6.2. Informative References
[I-D.ietf-idr-next-hop-capability]
Decraene, B., Kompella, K., and W. Henderickx, "BGP Next-
Hop dependent capabilities", Work in Progress, Internet-
Draft, draft-ietf-idr-next-hop-capability-08, 8 June 2022,
<https://www.ietf.org/archive/id/draft-ietf-idr-next-hop-
capability-08.txt>.
[I-D.scudder-bgp-entropy-label]
Scudder, J. and K. Kompella, "BGP Entropy Label
Capability, Version 2", Work in Progress, Internet-Draft,
draft-scudder-bgp-entropy-label-00, 28 April 2022,
<https://www.ietf.org/archive/id/draft-scudder-bgp-
entropy-label-00.txt>.
[RFC4786] Abley, J. and K. Lindqvist, "Operation of Anycast
Services", BCP 126, RFC 4786, DOI 10.17487/RFC4786,
December 2006, <https://www.rfc-editor.org/info/rfc4786>.
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[RFC5492] Scudder, J. and R. Chandra, "Capabilities Advertisement
with BGP-4", RFC 5492, DOI 10.17487/RFC5492, February
2009, <https://www.rfc-editor.org/info/rfc5492>.
[RFC8277] Rosen, E., "Using BGP to Bind MPLS Labels to Address
Prefixes", RFC 8277, DOI 10.17487/RFC8277, October 2017,
<https://www.rfc-editor.org/info/rfc8277>.
Appendix A. Other Means of Signaling EL Capability
A router that supports this specification could also have other means
to know that an egress is EL-capable, for example, it could support
ELCv2 [I-D.scudder-bgp-entropy-label], or it could know through
configuration. If a router learns through any means that an egress
is EL-capable, it MAY treat the egress as EL-capable. For example,
reception of a valid ELCv2 would be sufficient (even if a valid ELCv3
is not received), and similarly, reception of a valid ELCv3 would be
sufficient (even if a valid ELCv2 is not received). The details of
which methods are accepted for signaling EL capability are beyond the
scope of this specification but SHOULD be configurable by the user.
Acknowledgements
This specification derives from two earlier documents,
[I-D.ietf-idr-next-hop-capability] and
[I-D.scudder-bgp-entropy-label].
[I-D.ietf-idr-next-hop-capability] included the following
acknowledgements:
The Entropy Label Next-Hop Capability defined in this document is
based on the ELC BGP attribute defined in section 5.2 of [RFC6790].
The authors wish to thank John Scudder for the discussions on this
topic and Eric Rosen for his in-depth review of this document.
The authors wish to thank Jie Dong and Robert Raszuk for their
review and comments.
[I-D.scudder-bgp-entropy-label] included the following
acknowledgements:
Thanks to Swadesh Agrawal, Alia Atlas, Bruno Decraene, Martin
Djernaes, John Drake, Adrian Farrell, Keyur Patel, Toby Rees, and
Ravi Singh, for their discussion of this issue.
Contributors
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Serge Krier
Cisco Systems
Email: sekrier@cisco.com
Kevin Wang
Juniper Networks
Email: kfwang@juniper.net
Authors' Addresses
Bruno Decraene (editor)
Orange
Email: bruno.decraene@orange.com
John G. Scudder (editor)
Juniper Networks
Email: jgs@juniper.net
Wim Henderickx
Nokia
Email: wim.henderickx@nokia.com
Kireeti Kompella
Juniper Networks
Email: kireeti@juniper.net
Satya Mohanty
Cisco Systems
Email: satyamoh@cisco.com
James Uttaro
AT&T
Email: ju1738@att.com
Bin Wen
Comcast
Email: Bin_Wen@comcast.com
Decraene, et al. Expires 24 June 2023 [Page 13]