Egress Protection for Segment Routing (SR) networks
draft-hegde-rtgwg-egress-protection-sr-networks-01
Routing area S. Hegde
Internet-Draft W. Lin
Intended status: Standards Track Juniper Networks Inc.
Expires: May 19, 2021 P. Shaofu
ZTE Corporation
November 15, 2020
Egress Protection for Segment Routing (SR) networks
draft-hegde-rtgwg-egress-protection-sr-networks-01
Abstract
This document specifies a Fast Reroute(FRR) mechanism for protecting
IP/MPLS services that use Segment Routing (SR) paths for transport
against egress node and egress link failures. The mechanism is based
on egress protection framework described in [RFC8679]. The egress
protection mechanism can be further simplified in Segment Routing
networks with anycast SIDs and anycast Locators. This document
addresses all kinds of networks that use Segment Routing transport
such as SR-MPLS over IPv4, SR-MPLS over IPv6, SRv6 and SRm6.
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 RFC 2119 [RFC2119].
Status of This Memo
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provisions of BCP 78 and BCP 79.
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This Internet-Draft will expire on May 19, 2021.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Egress Node Protection . . . . . . . . . . . . . . . . . . . 3
2.1. SR-MPLS Networks . . . . . . . . . . . . . . . . . . . . 4
2.2. SRm6 Networks . . . . . . . . . . . . . . . . . . . . . . 5
2.3. SRv6 Networks . . . . . . . . . . . . . . . . . . . . . . 5
3. Egress Link Protection . . . . . . . . . . . . . . . . . . . 6
4. Security Considerations . . . . . . . . . . . . . . . . . . . 7
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7
6. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 7
7. References . . . . . . . . . . . . . . . . . . . . . . . . . 7
7.1. Normative References . . . . . . . . . . . . . . . . . . 7
7.2. Informative References . . . . . . . . . . . . . . . . . 8
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 9
1. Introduction
Segment Routing Architecture as defined in [RFC8402] provides a
simple and scalable MPLS control plane that removes state from
transit nodes in the network. SRm6 as defined in
[I-D.bonica-spring-sr-mapped-six] and SRv6 as defined in
[I-D.ietf-spring-srv6-network-programming] provide Segment Routing
transport in pure IPv6 networks where MPLS data plane is not used.
End-to-End resiliency is very important to satisfy Service Level
Agreements (SLA) such as 50ms convergence. The transport resiliency
and fast rerouting are described
in[I-D.ietf-rtgwg-segment-routing-ti-lfa] and
[I-D.ietf-spring-segment-protection-sr-te-paths]. Egress node and
egress link failures are not covered by these protection mechanisms.
Egress node and link failures need to address moving the services to
other nodes where the customer services are multi-homed. In
traditional MPLS networks service labels (ex: L3VPN) are assigned
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