Application-Specific Attributes Advertisement with BGP Link-State
draft-ietf-idr-bgp-ls-app-specific-attr-07
| Document | Type | Active Internet-Draft (idr WG) | |
|---|---|---|---|
| Authors | Ketan Talaulikar , Peter Psenak , Jeff Tantsura | ||
| Last updated | 2021-06-25 | ||
| Replaces | draft-ketant-idr-bgp-ls-app-specific-attr | ||
| Stream | Internet Engineering Task Force (IETF) | ||
| Intended RFC status | (None) | ||
| Formats | plain text pdf htmlized bibtex | ||
| Reviews | |||
| Stream | WG state | Submitted to IESG for Publication | |
| Document shepherd | Keyur Patel | ||
| Shepherd write-up | Show (last changed 2021-05-02) | ||
| IESG | IESG state | Publication Requested | |
| Action Holders |
(None)
|
||
| Consensus Boilerplate | Unknown | ||
| Telechat date | |||
| Responsible AD | Alvaro Retana | ||
| Send notices to | shares@ndzh.com, keyur@arrcus.com | ||
Inter-Domain Routing K. Talaulikar, Ed.
Internet-Draft P. Psenak
Intended status: Standards Track Cisco Systems
Expires: December 27, 2021 J. Tantsura
Microsoft
June 25, 2021
Application-Specific Attributes Advertisement with BGP Link-State
draft-ietf-idr-bgp-ls-app-specific-attr-07
Abstract
Various link attributes have been defined in link-state routing
protocols like OSPF and IS-IS in the context of the MPLS Traffic
Engineering (TE) and GMPLS. BGP Link-State (BGP-LS) extensions have
been defined to distribute these attributes along with other topology
information from these link-state routing protocols. Many of these
link attributes can be used for applications other than MPLS-TE or
GMPLS.
Extensions to link-state routing protocols have been defined for such
link attributes that enable distribution of their application-
specific values. This document defines extensions to BGP-LS address-
family to enable advertisement of these application-specific
attributes as a part of the topology information from the network.
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/.
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 December 27, 2021.
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Copyright Notice
Copyright (c) 2021 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 extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Requirements Language . . . . . . . . . . . . . . . . . . 3
2. Application Specific Link Attributes TLV . . . . . . . . . . 3
3. Application-Specific Link Attributes . . . . . . . . . . . . 5
4. Procedures . . . . . . . . . . . . . . . . . . . . . . . . . 7
5. Deployment Considerations . . . . . . . . . . . . . . . . . . 9
6. Backward Compatibility . . . . . . . . . . . . . . . . . . . 10
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10
8. Manageability Considerations . . . . . . . . . . . . . . . . 11
9. Security Considerations . . . . . . . . . . . . . . . . . . . 11
10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 11
11. References . . . . . . . . . . . . . . . . . . . . . . . . . 12
11.1. Normative References . . . . . . . . . . . . . . . . . . 12
11.2. Informative References . . . . . . . . . . . . . . . . . 12
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 14
1. Introduction
Various link attributes have been defined in link-state routing
protocols (viz., IS-IS [RFC1195], OSPFv2 [RFC2328] and OSPFv3
[RFC5340] ) in the context of the MPLS traffic engineering and GMPLS.
All these attributes are distributed by these protocols using TLVs
that were originally defined for traditional MPLS Traffic Engineering
(i.e., using RSVP-TE [RFC3209]) or GMPLS [RFC4202] applications.
In recent years new applications have been introduced that have use
cases for many of the link attributes historically used by RSVP-TE
and GMPLS. Such applications include Segment Routing (SR) Policy
[RFC8402] and Loop Free Alternates (LFA) [RFC5286]. This has
introduced ambiguity in that if a deployment includes a mix of RSVP-
TE support and SR Policy support (for example) it is not possible to
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unambiguously indicate which advertisements are to be used by RSVP-TE
and which advertisements are to be used by SR Policy. If the
topologies are fully congruent this may not be an issue, but any
incongruence leads to ambiguity. An additional issue arises in cases
where both applications are supported on a link but the link
attribute values associated with each application differ. Current
advertisements do not support advertising application-specific values
for the same attribute on a specific link.
[RFC8920] and [RFC8919] define extensions for OSPF and IS-IS
respectively that address these issues. Also, as the evolution of
use cases for link attributes can be expected to continue in the
years to come, these documents define an easily extensible solution
for the introduction of new applications and new use cases.
BGP Link-State extensions [RFC7752] have been specified to enable
distribution of the link-state topology information from the IGPs to
an application like a controller or Path Computation Engine (PCE) via
BGP. The controller/PCE gets the end-to-end topology information
across IGP domains so it can perform path computations for use cases
like end-to-end traffic engineering (TE) using RSVP-TE or SR Policy
mechanisms. A similar challenge to what was described above is hence
also faced by such centralized computation entities.
There is thus a need for BGP-LS extensions to also report link
attributes on a per-application basis on the same lines as introduced
in the link-state routing protocols. This document defines these
BGP-LS extensions and also covers the backward compatibility issues
related to existing BGP-LS deployments.
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. Application Specific Link Attributes TLV
The BGP-LS [RFC7752] specifies the Link NLRI for the advertisement of
links and their attributes using the BGP-LS Attribute. The
Application-Specific Link Attributes (ASLA) TLV is a new optional
top-level BGP-LS Attribute TLV that is introduced for Link NLRIs. It
is defined such that it may act as a container for certain existing
and future link attributes that require application-specific
definition.
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The format of this TLV is as follows and is similar to the
corresponding ASLA sub-TLVs defined for OSPF and IS-IS in [RFC8920]
and [RFC8919] respectively.
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SABM Length | UDABM Length | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Standard Application Identifier Bit Mask (variable) //
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| User-Defined Application Identifier Bit Mask (variable) //
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Attribute sub-TLVs //
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1: Application-Specific Link Attributes TLV
where:
o Type: 1122
o Length: variable.
o SABM Length : Standard Application Identifier Bit Mask Length in
octets. The values MUST be 0, 4, or 8. If the Standard
Application Identifier Bit Mask is not present, the value MUST be
set to 0.
o UDABM Length : User-Defined Application Identifier Bit Mask Length
in octets. The values MUST be 0, 4, or 8. If the User-Defined
Application Identifier Bit Mask is not present, the value MUST be
set to 0.
o Standard Application Identifier Bit Mask : of size 0, 4, or 8
octets as indicated by the SABML. An optional set of bits, where
each bit represents a single standard application. The bits are
defined in the IANA "IGP Parameters" registries under the "Link
Attribute Applications" registry [RFC8919].
o User-Defined Application Identifier Bit Mask : of size 0, 4, or 8
octets as indicated by the UDABML. An optional set of bits, where
each bit represents a single user-defined application. The bits
are not managed or assigned by IANA or any other standards body
and definition is left to the implementation.
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o sub-TLVs : BGP-LS Attribute TLVs corresponding to the Link NLRI
that are application-specific (as specified in Section 3) are
included as sub-TLVs of the ASLA TLV.
An ASLA TLV with both the SABM and UDABM lengths set to 0 (i.e.
without any application identifier bit masks) indicates that the link
attribute sub-TLVs that it encloses are applicable for all
applications. However, the link attributes advertised within an ASLA
TLV with such a zero-length application bit mask MUST NOT be
considered by BGP-LS consumers for those applications for which at
least one instance of ASLA TLV is present in the same advertisement
with their specific application bit set.
The ASLA TLV and its sub-TLVs can only be added to the BGP-LS
Attribute associated with the Link NLRI of the node that originates
the underlying IGP link attribute TLVs/sub-TLVs. The procedures for
originating link attributes in the ASLA TLV from underlying IGPs are
specified in Section 4.
When the node is not running any of the IGPs but running a protocol
like BGP, then the link attributes for the node's local links MAY be
originated as part of the BGP-LS Attribute using the ASLA TLV and its
sub-TLVs within the Link NLRI corresponding to the local node.
3. Application-Specific Link Attributes
Several BGP-LS Attribute TLVs corresponding to the Link NLRI are
defined in BGP-LS and more may be added in the future. The following
types of link attributes are required to be considered application-
specific.
o those that have different values for different applications e.g.,
a different TE metric value used for RSVP-TE than for SR Policy
o those that apply to multiple applications but need to be used only
by a specific application e.g., certain Shared Risk Link Group
(SRLG) values are configured on a node for LFA but the same do not
need to be used for RSVP-TE
The following table lists the currently defined BGP-LS Attributes
TLVs corresponding to Link NLRI that have application-specific
semantics. These were originally defined with semantics for RSVP-TE
and GMPLS applications.
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+-----------+---------------------+---------------------------------+
| TLV Code | Description | Reference Document |
| Point | | |
+-----------+---------------------+---------------------------------+
| 1088 | Administrative | [RFC7752] |
| | group (color) | |
| 1092 | TE Default Metric | [RFC7752] |
| 1096 | Shared Risk Link | [RFC7752] |
| | Group | |
| 1114 | Unidirectional Link | [RFC8571] |
| | Delay | |
| 1115 | Min/Max | [RFC8571] |
| | Unidirectional Link | |
| | Delay | |
| 1116 | Unidirectional | [RFC8571] |
| | Delay Variation | |
| 1117 | Unidirectional Link | [RFC8571] |
| | Loss | |
| 1118 | Unidirectional | [RFC8571] |
| | Residual Bandwidth | |
| 1119 | Unidirectional | [RFC8571] |
| | Available Bandwidth | |
| 1120 | Unidirectional | [RFC8571] |
| | Utilized Bandwidth | |
| 1173 | Extended | [I-D.ietf-idr-eag-distribution] |
| | Administrative | |
| | Group | |
+-----------+---------------------+---------------------------------+
Table 1: BGP-LS Attribute TLVs also used as sub-TLVs of ASLA TLV
All the BGP-LS Attribute TLVs defined in the table above are
RECOMMENDED to continue to be advertised at the top-level in the BGP-
LS Attribute for carrying attributes specific to RSVP-TE without the
use of the ASLA TLV.
When a new link attribute is introduced, it may be thought of as
being specific to only a single application. However, subsequently,
it may be also shared by other applications and/or require
application-specific values. In such cases, it is RECOMMENDED to err
on the side of caution and define such attributes as application-
specific to ensure flexibility in the future.
BGP-LS Attribute TLVs corresponding to Link NLRI that are defined in
the future MUST specify if they are application-specific and hence
are REQUIRED to be encoded within an ASLA TLV.
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Only application-specific link attributes need to be advertised
within the ASLA TLV. Link attributes that do not have application-
specific semantics MUST NOT be advertised within the ASLA TLV.
Receivers MUST ignore any non-application-specific attribute sub-TLVs
within the ASLA TLV.
When the same application-specific link attributes are advertised
both within the ASLA TLV and as top-level TLVs in the BGP-LS
Attribute, the attributes advertised within the ASLA TLV take
precedence for the applications indicated in the ASLA TLV encoding.
4. Procedures
The procedures described in this section apply to networks where all
BGP-LS originators and consumers support this specification. The
backward compatibility aspects and operations in deployments where
there are some BGP-LS originators or consumers that do not support
this specification are described further in Section 6.
The BGP-LS originator learns of the association of an application-
specific attribute to one or more applications from either the
underlying IGP protocol LSA/LSPs from which it is advertising the
topology information or from the local node configuration when
advertising attributes for the local node only.
The association of an application-specific link attribute with a
specific application context when advertising attributes for the
local node only (e.g., when running BGP as the only routing protocol)
is an implementation-specific matter and outside the scope of this
document.
[RFC8920] and [RFC8919] specify the mechanisms for advertising
application-specific link attributes in OSPFv2/v3 and IS-IS
respectively. These IGP specifications also describe the backward
compatibility aspects and the existing RSVP-TE/GMPLS specific TLV
encoding mechanisms in the respective protocols.
A BGP-LS originator node that is advertising link-state information
from the underlying IGP determines the protocol encoding of
application-specific link attributes based on the following rules:
1. Application-specific link attributes received from an IGP node
using existing RSVP-TE/GMPLS encodings MUST be encoded using the
respective BGP-LS top-level TLVs listed in Table 1.
2. Application-specific link attributes received from an OSPF node
using ASLA sub-TLV or from an IS-IS node using either ASLA sub-
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TLV or ASLA SRLG TLV MUST be encoded in the BGP-LS ASLA TLV as
sub-TLVs.
3. In the case of IS-IS, the following specific procedures are to be
followed:
A. When application-specific link attributes are received from a
node with the L bit set in the ASLA sub-TLV and application
bits other than RSVP-TE are set in the application bit masks
then the application-specific link attributes advertised in
the corresponding legacy IS-IS TLVs/sub-TLVs MUST be encoded
within the BGP-LS ASLA TLV as sub-TLVs with the application
bits, other than the RSVP-TE bit, copied from the IS-IS ASLA
sub-TLV. The link attributes advertised in the legacy IS-IS
TLVs/sub-TLVs are also advertised in BGP-LS top-level TLVs
listed in Table 1. Note that this is true regardless of
whether the RSVP-TE bit was set in the IS-IS ASLA TLV/sub-
TLV. The same procedure also applies for the advertisement
of the SRLG values from the IS-IS ASLA SRLG TLV within the
BGP-LS SRLG TLV (1096) both at the top-level and within the
BGP-LS ASLA TLV.
B. When the ASLA sub-TLV has the RSVP-TE application bit set,
then the link attributes for the corresponding ASLA sub-TLV
MUST be encoded using the respective BGP-LS top-level TLVs
listed in Table 1. Similarly, when the ASLA SRLG TLV has the
RSVP-TE application bit set, then the SRLG values within it
MUST be encoded using the top-level BGP-LS SRLG TLV (1096).
C. A merge of the SRLG values advertised in IS-IS SRLG ASLA TLVs
and the other link attributes advertised in IS-IS ASLA sub-
TLVs, on a per-application basis, is REQUIRED for all
applications that have their bit set in the SABM/UDABM in at
least one of the aforementioned TLV types. When performing
this merge, only the TLVs with the application's bit set in
SABM/UDABM MUST be used when such TLVs are available from
either TLV types. If the bit for an application is set in
the SABM/UDABM of only one of the TLV types, then the
attributes from the other TLV type with zero-length
application bit mask MUST be also selected for that
application, if such TLV is available. Such merged link
attributes are advertised in a per application instance of
the BGP-LS ASLA TLV.
D. If the resulting set of merged link attributes and SRLG
values is common across multiple applications, they MAY be
advertised in a common BGP-LS ASLA TLV instance where the
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bits for all such applications would be set in the
application bit mask.
E. Both the SRLG values from IS-IS ASLA SRLG TLVs and the link
attributes from IS-IS ASLA sub-TLVs, with the zero-length
application bit mask, MUST be advertised into a BGP-LS ASLA
TLV with a zero-length application bit mask, independent of
the merging described above.
F. [RFC8919] allows the advertisement of the Maximum Link
Bandwidth within an ASLA sub-TLV even though it is not an
application-specific attribute. However, when originating
the Maximum Link Bandwidth into BGP-LS, the attribute MUST be
encoded only in the top-level BGP-LS Maximum Link Bandwidth
TLV (1089) and the receiver MUST ignore them when advertised
within the BGP-LS ASLA TLV.
G. [RFC8919] also allows the advertisement of the Maximum
Reservable Link Bandwidth and the Unreserved Bandwidth within
an ASLA sub-TLV even though these attributes are specific to
RSVP-TE application. However, when originating the Maximum
Reservable Link Bandwidth and Unreserved Bandwidth into BGP-
LS, these attributes MUST be encoded only in the BGP-LS top-
level Maximum Reservable Link Bandwidth TLV (1090) and
Unreserved Bandwidth TLV (1091) respectively and not within
the BGP-LS ASLA TLV.
These rules ensure that a BGP-LS originator performs the
advertisement for all application-specific link attributes from the
IGP nodes that support or do not support the ASLA extension.
Furthermore, it also ensures that the top-level BGP-LS TLVs defined
for RSVP-TE and GMPLS applications continue to be used for
advertisement of their application-specific attributes.
A BGP-LS consumer node would normally receive all the application-
specific link attributes corresponding to RSVP-TE and GMPLS
applications as existing top-level BGP-LS TLVs while for other
applications they are encoded in ASLA TLV(s) with appropriate
applicable bit mask setting. A BGP-LS consumer that supports this
specification SHOULD prefer the application-specific attribute value
received via sub-TLVs within the ASLA TLV over the value received via
the top-level TLVs.
5. Deployment Considerations
SR Policy and LFA applications have been deployed in some networks
using the IGP link attributes defined originally for RSVP-TE as
discussed in [RFC8920] and [RFC8919]. The corresponding BGP-LS top-
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level link attribute TLVs originally defined for RSVP-TE have also
been similarly used for SR Policy and LFA applications by BGP-LS
consumers. Such usage MAY continue without requiring the support of
the application-specific link attribute encodings described in this
document as long as the following conditions are met:
o The application is SR Policy or LFA and RSVP-TE is not deployed
anywhere in the network
o The application is SR Policy or LFA, RSVP-TE is deployed in the
network, and both the set of links on which SR Policy and/or LFA
advertisements are required and the attribute values used by SR
Policy and/or LFA on all such links is fully congruent with the
links and attribute values used by RSVP-TE
6. Backward Compatibility
The backward compatibility aspects for BGP-LS are associated with the
originators (i.e., nodes) and consumers (e.g., PCE, controllers,
applications, etc.) of the topology information. BGP-LS
implementations have been originating link attributes and consuming
them without any application-specific scoping prior to the extensions
specified in this document.
IGP backward compatibility aspects associated with application-
specific link attributes for RSVP-TE, SR Policy, and LFA applications
are discussed in the Backward Compatibility sections of [RFC8920] and
[RFC8919]. While those backward compatibility aspects ensure
compatibility of IGP advertisements, they also serve to ensure the
backward compatibility of the BGP-LS advertisements used by BGP-LS
consumers. In deployments where the BGP-LS originators or consumers
do not support the extensions specified in this document, the IGPs
need to continue to advertise link attributes intended for use by SR
Policy and LFA applications using the RSVP-TE/GMPLS encodings. This
allows BGP-LS advertisements to be consistent with the behavior prior
to the extensions defined in this document
It is RECOMMENDED that nodes that support this specification are
selected as originators of BGP-LS information when advertising the
link-state information from the IGPs.
7. IANA Considerations
This document requests assignment of code-points from the registry
"BGP-LS Node Descriptor, Link Descriptor, Prefix Descriptor, and
Attribute TLVs" based on the table below which reflects the values
assigned via the early allocation process. The column "IS-IS TLV/
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Sub-TLV" defined in the registry does not require any value and
should be left empty.
+------------+------------------------------------------+----------+
| Code Point | Description | Length |
+------------+------------------------------------------+----------+
| 1122 | Application-Specific Link Attributes TLV | variable |
+------------+------------------------------------------+----------+
8. Manageability Considerations
The new protocol extensions introduced in this document augment the
existing IGP topology information defined in [RFC7752]. Procedures
and protocol extensions defined in this document do not affect the
BGP protocol operations and management other than as discussed in the
Manageability Considerations section of [RFC7752]. Specifically, the
malformed NLRIs attribute tests in the Fault Management section of
[RFC7752] now encompasses the BGP-LS TLVs defined in this document.
The extensions specified in this document do not specify any new
configuration or monitoring aspects in BGP or BGP-LS. The
specification of BGP models is an ongoing work based on
[I-D.ietf-idr-bgp-model].
9. Security Considerations
The procedures and protocol extensions defined in this document do
not affect the BGP security model. See the "Security Considerations"
section of [RFC4271] for a discussion of BGP security. Also, refer
to [RFC4272] and [RFC6952] for analyses of security issues for BGP.
Security considerations for acquiring and distributing BGP-LS
information are discussed in [RFC7752]. The TLVs introduced in this
document are used to propagate the application-specific link
attributes IGP extensions defined in [RFC8919] and [RFC8920]. It is
assumed that the IGP instances originating these TLVs will support
all the required security (as described in [RFC8919] and [RFC8920])
in order to prevent any security issues when propagating the TLVs
into BGP-LS. The advertisement of the link attribute information
defined in this document presents no significant additional risk
beyond that associated with the existing link attribute information
already supported in [RFC7752].
10. Acknowledgements
The authors would like to thank Les Ginsberg, Baalajee S, Amalesh
Maity, Acee Lindem, Keyur Patel, Paul Wouters, and Rudy Selderslaghs
for their review and feedback on this document.
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11. References
11.1. 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>.
[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>.
[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>.
[RFC8919] Ginsberg, L., Psenak, P., Previdi, S., Henderickx, W., and
J. Drake, "IS-IS Application-Specific Link Attributes",
RFC 8919, DOI 10.17487/RFC8919, October 2020,
<https://www.rfc-editor.org/info/rfc8919>.
[RFC8920] Psenak, P., Ed., Ginsberg, L., Henderickx, W., Tantsura,
J., and J. Drake, "OSPF Application-Specific Link
Attributes", RFC 8920, DOI 10.17487/RFC8920, October 2020,
<https://www.rfc-editor.org/info/rfc8920>.
11.2. Informative References
[I-D.ietf-idr-bgp-model]
Jethanandani, M., Patel, K., Hares, S., and J. Haas, "BGP
YANG Model for Service Provider Networks", draft-ietf-idr-
bgp-model-10 (work in progress), November 2020.
[I-D.ietf-idr-eag-distribution]
Tantsura, J., Wang, Z., Wu, Q., and K. Talaulikar,
"Distribution of Traffic Engineering Extended
Administrative Groups using BGP-LS", draft-ietf-idr-eag-
distribution-19 (work in progress), June 2021.
[RFC1195] Callon, R., "Use of OSI IS-IS for routing in TCP/IP and
dual environments", RFC 1195, DOI 10.17487/RFC1195,
December 1990, <https://www.rfc-editor.org/info/rfc1195>.
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[RFC2328] Moy, J., "OSPF Version 2", STD 54, RFC 2328,
DOI 10.17487/RFC2328, April 1998,
<https://www.rfc-editor.org/info/rfc2328>.
[RFC3209] Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V.,
and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP
Tunnels", RFC 3209, DOI 10.17487/RFC3209, December 2001,
<https://www.rfc-editor.org/info/rfc3209>.
[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>.
[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>.
[RFC4272] Murphy, S., "BGP Security Vulnerabilities Analysis",
RFC 4272, DOI 10.17487/RFC4272, January 2006,
<https://www.rfc-editor.org/info/rfc4272>.
[RFC5286] Atlas, A., Ed. and A. Zinin, Ed., "Basic Specification for
IP Fast Reroute: Loop-Free Alternates", RFC 5286,
DOI 10.17487/RFC5286, September 2008,
<https://www.rfc-editor.org/info/rfc5286>.
[RFC5340] Coltun, R., Ferguson, D., Moy, J., and A. Lindem, "OSPF
for IPv6", RFC 5340, DOI 10.17487/RFC5340, July 2008,
<https://www.rfc-editor.org/info/rfc5340>.
[RFC6952] Jethanandani, M., Patel, K., and L. Zheng, "Analysis of
BGP, LDP, PCEP, and MSDP Issues According to the Keying
and Authentication for Routing Protocols (KARP) Design
Guide", RFC 6952, DOI 10.17487/RFC6952, May 2013,
<https://www.rfc-editor.org/info/rfc6952>.
[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>.
[RFC8571] Ginsberg, L., Ed., Previdi, S., Wu, Q., Tantsura, J., and
C. Filsfils, "BGP - Link State (BGP-LS) Advertisement of
IGP Traffic Engineering Performance Metric Extensions",
RFC 8571, DOI 10.17487/RFC8571, March 2019,
<https://www.rfc-editor.org/info/rfc8571>.
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Authors' Addresses
Ketan Talaulikar (editor)
Cisco Systems
India
Email: ketant@cisco.com
Peter Psenak
Cisco Systems
Slovakia
Email: ppsenak@cisco.com
Jeff Tantsura
Microsoft
Email: jefftant.ietf@gmail.com
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