Internet DRAFT - draft-ietf-bier-te-ospf
draft-ietf-bier-te-ospf
Network Working Group H. Chen
Internet-Draft M. McBride
Intended status: Standards Track Futurewei
Expires: 10 September 2023 A. Wang
China Telecom
G. Mishra
Verizon Inc.
Y. Fan
Casa Systems
L. Liu
Fujitsu
X. Liu
IBM Corporation
9 March 2023
OSPF Extensions for BIER-TE
draft-ietf-bier-te-ospf-04
Abstract
This document describes OSPF extensions for distributing BitPositions
configured on the links in "Bit Index Explicit Replication Traffic
Engineering" (BIER-TE) domain.
Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119] [RFC8174]
when, and only when, they appear in all capitals, as shown here.
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 10 September 2023.
Chen, et al. Expires 10 September 2023 [Page 1]
Internet-Draft OSPF for BIER-TE March 2023
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 to this document. Code Components
extracted from this document must 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 . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 2
2. Extensions to OSPFv2 . . . . . . . . . . . . . . . . . . . . 3
3. Security Considerations . . . . . . . . . . . . . . . . . . . 5
4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 5
5. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 5
6. References . . . . . . . . . . . . . . . . . . . . . . . . . 5
6.1. Normative References . . . . . . . . . . . . . . . . . . 5
6.2. Informative References . . . . . . . . . . . . . . . . . 6
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 6
1. Introduction
[RFC9262] introduces Bit Index Explicit Replication (BIER) Traffic/
Tree Engineering (BIER-TE). It is an architecture for per-packet
stateless explicit point to multipoint (P2MP) multicast path/tree. A
link in a BIER-TE domain has its BitPositions. For a link between
two nodes X and Y, there are two BitPositions for two forward
connected adjacencies. These two adjacency BitPositions could be
configured on nodes X and Y respectively. The BitPosition configured
on X is the forward connected adjacency of Y. The BitPosition
configured on Y is the forward connected adjacency of X.
This document proposes OSPF extensions for distributing BitPositions
configured on the links in "Bit Index Explicit Replication Traffic
Engineering" (BIER-TE) domain.
1.1. Terminology
BIER: Bit Index Explicit Replication.
BIER-TE: BIER Traffic Engineering.
Chen, et al. Expires 10 September 2023 [Page 2]
Internet-Draft OSPF for BIER-TE March 2023
BFR: Bit-Forwarding Router.
BFIR: Bit-Forwarding Ingress Router.
BFER: Bit-Forwarding Egress Router.
BFR-id: BFR Identifier. It is a number in the range [1,65535].
BFR-NBR: BFR Neighbor.
LSA: Link State Advertisement.
OSPF: Open Shortest Path First.
2. Extensions to OSPFv2
This section describes protocol extensions to OSPFv2 for distributing
BIER-TE information such as the BitPositions configured on the links
in a BIER-TE domain.
[RFC7684] defines the OSPFv2 Extended Link TLV to advertise the
information about a link. Multiple Link TLVs for the links of a
router are included in the OSPFv2 Extended Link Opaque LSA of the
router. The OSPFv2 Extended Link 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 (1) | Length (Variable) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Type | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Data |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sub-TLVs (variable) |
~ ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1: OSPFv2 Extended Link TLV
Type: 1.
Length: Variable, dependent on Sub-TLVs.
Link Type, Link ID and Link Data: They are defined in Section A.4.2
Chen, et al. Expires 10 September 2023 [Page 3]
Internet-Draft OSPF for BIER-TE March 2023
of [RFC2328].
Reserved: MUST be set to 0 on transmission and MUST be ignored on
reception.
Under the OSPFv2 Extended Link TLV for a link, a Sub-TLV, called
BIER-TE Sub-TLV, is defined for distributing BIER-TE information
about the link. A BIER-TE Sub-TLV is included in the Link TLV for a
link of Link Type Point-to-Point or Broadcast (or say LAN or Transit
Network). The BIER-TE 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 (TBD1) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| sub-domain-id | MT-ID | BAR | IPA |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| BitPosition | DrEndBitPosition |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2: BIER-TE Sub-TLV
Type: TBD1 is to be assigned by IANA.
Length: Variable.
sub-domain-id: Unique value identifying a BIER-TE sub-domain.
MT-ID: Multi-Topology ID identifying the topology that is associated
with the BIER-TE sub-domain.
BAR: Single-octet BIER Algorithm used to calculate underlay paths to
reach other BFRs. Values are allocated from the "BIER
Algorithm" registry defined in [RFC8401].
IPA: Single-octet IGP Algorithm used to either modify, enhance, or
replace the calculation of underlay paths to reach other BFRs
as defined by the BAR value. Values are defined in the "IGP
Algorithm Types" registry.
BitPosition: A 2-octet field encoding the BitPosition locally
configured on the link/interface when the Link Type of the link
in the OSPFv2 Extended Link TLV containing this Sub-TLV is 1
(i.e., Point-to-Point connection to another router) or 2 (i.e.,
connection to Transit Network or say LAN).
Chen, et al. Expires 10 September 2023 [Page 4]
Internet-Draft OSPF for BIER-TE March 2023
DrEndBitPosition: A 2-octet field encoding the BitPosition of the
connection on the designated router (DR) end. This field is
valid when the Link Type in the OSPFv2 Extended Link TLV
containing this Sub-TLV is 2 (i.e., Transit Network or LAN).
For the other value of the Link Type, this field MUST be
ignored. The DrEndBitPosition may be configured on the link/
interface to a transit network (i.e., broadcast link or say
LAN) as described in [I-D.chen-bier-te-lan].
3. Security Considerations
Protocol extensions defined in this document do not affect the OSPF
security other than those as discussed in the Security Considerations
section of [RFC7684].
4. IANA Considerations
Under "OSPFv2 Extended Link TLV Sub-TLVs registry" as defined in
[RFC7684], IANA is requested to assign a new registry value for BIER-
TE Sub-TLV as follows:
+==============+===================+=====================+
| Value | Description | reference |
+==============+===================+=====================+
| TBD1 (25) | BIER-TE | This document |
+--------------+-------------------+---------------------+
5. Acknowledgements
The authors would like to thank Acee Lindem, Les Ginsberg, Tony
Przygienda and Toerless Eckert for their comments on this work.
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>.
[RFC2328] Moy, J., "OSPF Version 2", STD 54, RFC 2328,
DOI 10.17487/RFC2328, April 1998,
<https://www.rfc-editor.org/info/rfc2328>.
Chen, et al. Expires 10 September 2023 [Page 5]
Internet-Draft OSPF for BIER-TE March 2023
[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>.
[RFC8279] Wijnands, IJ., Ed., Rosen, E., Ed., Dolganow, A.,
Przygienda, T., and S. Aldrin, "Multicast Using Bit Index
Explicit Replication (BIER)", RFC 8279,
DOI 10.17487/RFC8279, November 2017,
<https://www.rfc-editor.org/info/rfc8279>.
[RFC9262] Eckert, T., Ed., Menth, M., and G. Cauchie, "Tree
Engineering for Bit Index Explicit Replication (BIER-TE)",
RFC 9262, DOI 10.17487/RFC9262, October 2022,
<https://www.rfc-editor.org/info/rfc9262>.
6.2. Informative References
[I-D.chen-bier-te-lan]
Chen, H., McBride, M., Wang, A., Mishra, G. S., Liu, L.,
and X. Liu, "BIER-TE for Broadcast Link", Work in
Progress, Internet-Draft, draft-chen-bier-te-lan-04, 22
December 2022, <https://datatracker.ietf.org/doc/html/
draft-chen-bier-te-lan-04>.
[RFC8296] Wijnands, IJ., Ed., Rosen, E., Ed., Dolganow, A.,
Tantsura, J., Aldrin, S., and I. Meilik, "Encapsulation
for Bit Index Explicit Replication (BIER) in MPLS and Non-
MPLS Networks", RFC 8296, DOI 10.17487/RFC8296, January
2018, <https://www.rfc-editor.org/info/rfc8296>.
[RFC8401] Ginsberg, L., Ed., Przygienda, T., Aldrin, S., and Z.
Zhang, "Bit Index Explicit Replication (BIER) Support via
IS-IS", RFC 8401, DOI 10.17487/RFC8401, June 2018,
<https://www.rfc-editor.org/info/rfc8401>.
Authors' Addresses
Huaimo Chen
Futurewei
Boston, MA,
United States of America
Email: Huaimo.chen@futurewei.com
Chen, et al. Expires 10 September 2023 [Page 6]
Internet-Draft OSPF for BIER-TE March 2023
Mike McBride
Futurewei
Email: michael.mcbride@futurewei.com
Aijun Wang
China Telecom
Beiqijia Town, Changping District
Beijing
102209
China
Email: wangaj3@chinatelecom.cn
Gyan S. Mishra
Verizon Inc.
13101 Columbia Pike
Silver Spring, MD 20904
United States of America
Phone: 301 502-1347
Email: gyan.s.mishra@verizon.com
Yanhe Fan
Casa Systems
United States of America
Email: yfan@casa-systems.com
Lei Liu
Fujitsu
United States of America
Email: liulei.kddi@gmail.com
Xufeng Liu
IBM Corporation
United States of America
Email: xufeng.liu.ietf@gmail.com
Chen, et al. Expires 10 September 2023 [Page 7]