PCEP extension to support Segment Routing Policy Candidate Paths
draft-ietf-pce-segment-routing-policy-cp-00
PCE Working Group M. Koldychev
Internet-Draft Cisco Systems, Inc.
Intended status: Standards Track S. Sivabalan
Expires: December 26, 2020 Ciena Corporation
C. Barth
Juniper Networks, Inc.
S. Peng
Huawei Technologies
H. Bidgoli
Nokia
June 24, 2020
PCEP extension to support Segment Routing Policy Candidate Paths
draft-ietf-pce-segment-routing-policy-cp-00
Abstract
This document introduces a mechanism to specify a Segment Routing
(SR) policy, as a collection of SR candidate paths. An SR policy is
identified by <headend, color, end-point> tuple. An SR policy can
contain one or more candidate paths where each candidate path is
identified in PCEP via an PLSP-ID. This document proposes extension
to PCEP to support association among candidate paths of a given SR
policy. The mechanism proposed in this document is applicable to
both MPLS and IPv6 data planes of SR.
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.
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
Koldychev, et al. Expires December 26, 2020 [Page 1]
Internet-Draft SR Policy June 2020
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 26, 2020.
Copyright Notice
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. Motivation . . . . . . . . . . . . . . . . . . . . . . . . . 5
3.1. Group Candidate Paths belonging to the same SR policy . . 5
3.2. Instantiation of SR policy candidate paths . . . . . . . 5
3.3. Avoid computing lower preference candidate paths . . . . 5
3.4. Minimal signaling overhead . . . . . . . . . . . . . . . 6
4. Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . 6
4.1. Overview . . . . . . . . . . . . . . . . . . . . . . . . 6
4.2. Choice of Association Parameters . . . . . . . . . . . . 8
4.3. Multiple Optimization Objectives and Constraints . . . . 8
5. SR Policy Association Group . . . . . . . . . . . . . . . . . 9
5.1. SR Policy Identifiers TLV . . . . . . . . . . . . . . . . 10
5.2. SR Policy Name TLV . . . . . . . . . . . . . . . . . . . 10
5.3. SR Policy Candidate Path Identifiers TLV . . . . . . . . 11
5.4. SR Policy Candidate Path Name TLV . . . . . . . . . . . . 12
5.5. SR Policy Candidate Path Preference TLV . . . . . . . . . 13
6. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . 13
6.1. PCC Initiated SR Policy with single candidate-path . . . 13
6.2. PCC Initiated SR Policy with multiple candidate-paths . . 14
6.3. PCE Initiated SR Policy with single candidate-path . . . 14
6.4. PCE Initiated SR Policy with multiple candidate-paths . . 15
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