BGP Link-State Shortest Path First (SPF) Routing
draft-ietf-lsvr-bgp-spf-13
| Document | Type | Active Internet-Draft (lsvr WG) | |
|---|---|---|---|
| Authors | Keyur Patel , Acee Lindem , Shawn Zandi , Wim Henderickx | ||
| Last updated | 2021-02-22 | ||
| Replaces | draft-keyupate-lsvr-bgp-spf | ||
| Stream | IETF | ||
| Intended RFC status | Proposed Standard | ||
| Formats | plain text pdf htmlized (tools) htmlized bibtex | ||
| Reviews | |||
| Stream | WG state | WG Document | |
| Document shepherd | Victor Kuarsingh | ||
| Shepherd write-up | Show (last changed 2020-05-26) | ||
| IESG | IESG state | AD is watching | |
| Action Holders |
(None)
|
||
| Consensus Boilerplate | Yes | ||
| Telechat date | |||
| Responsible AD | Alvaro Retana | ||
| Send notices to | Gunter Van de Velde <gunter.van_de_velde@nokia.com>, aretana.ietf@gmail.com, victor@jvknet.com | ||
Network Working Group K. Patel
Internet-Draft Arrcus, Inc.
Intended status: Standards Track A. Lindem
Expires: August 26, 2021 Cisco Systems
S. Zandi
LinkedIn
W. Henderickx
Nokia
February 22, 2021
BGP Link-State Shortest Path First (SPF) Routing
draft-ietf-lsvr-bgp-spf-13
Abstract
Many Massively Scaled Data Centers (MSDCs) have converged on
simplified layer 3 routing. Furthermore, requirements for
operational simplicity have led many of these MSDCs to converge on
BGP as their single routing protocol for both their fabric routing
and their Data Center Interconnect (DCI) routing. This document
describes extensions to BGP to use BGP Link-State distribution and
the Shortest Path First (SPF) algorithm used by Internal Gateway
Protocols (IGPs) such as OSPF. In doing this, it allows BGP to be
efficiently used as both the underlay protocol and the overlay
protocol in MSDCs.
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 August 26, 2021.
Patel, et al. Expires August 26, 2021 [Page 1]
Internet-Draft BGP Link-State SPF Routing February 2021
Copyright Notice
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4
1.2. BGP Shortest Path First (SPF) Motivation . . . . . . . . 4
1.3. Document Overview . . . . . . . . . . . . . . . . . . . . 6
1.4. Requirements Language . . . . . . . . . . . . . . . . . . 6
2. Base BGP Protocol Relationship . . . . . . . . . . . . . . . 6
3. BGP Link-State (BGP-LS) Relationship . . . . . . . . . . . . 7
4. BGP Peering Models . . . . . . . . . . . . . . . . . . . . . 8
4.1. BGP Single-Hop Peering on Network Node Connections . . . 8
4.2. BGP Peering Between Directly-Connected Nodes . . . . . . 8
4.3. BGP Peering in Route-Reflector or Controller Topology . . 9
5. BGP Shortest Path Routing (SPF) Protocol Extensions . . . . . 9
5.1. BGP-LS Shortest Path Routing (SPF) SAFI . . . . . . . . . 9
5.1.1. BGP-LS-SPF NLRI TLVs . . . . . . . . . . . . . . . . 9
5.1.2. BGP-LS Attribute . . . . . . . . . . . . . . . . . . 10
5.2. Extensions to BGP-LS . . . . . . . . . . . . . . . . . . 11
5.2.1. Node NLRI Usage . . . . . . . . . . . . . . . . . . . 11
5.2.1.1. Node NLRI Attribute SPF Capability TLV . . . . . 11
5.2.1.2. BGP-LS-SPF Node NLRI Attribute SPF Status TLV . . 12
5.2.2. Link NLRI Usage . . . . . . . . . . . . . . . . . . . 13
5.2.2.1. BGP-LS-SPF Link NLRI Attribute Prefix-Length TLVs 14
5.2.2.2. BGP-LS-SPF Link NLRI Attribute SPF Status TLV . . 14
5.2.3. IPv4/IPv6 Prefix NLRI Usage . . . . . . . . . . . . . 15
5.2.3.1. BGP-LS-SPF Prefix NLRI Attribute SPF Status TLV . 16
5.2.4. BGP-LS Attribute Sequence-Number TLV . . . . . . . . 16
5.3. NEXT_HOP Manipulation . . . . . . . . . . . . . . . . . . 17
6. Decision Process with SPF Algorithm . . . . . . . . . . . . . 18
6.1. BGP NLRI Selection . . . . . . . . . . . . . . . . . . . 19
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