Path Computation Element Communication Protocol (PCEP) Extensions for Associated Bidirectional Segment Routing (SR) Paths
draft-ietf-pce-sr-bidir-path-05
PCE Working Group C. Li
Internet-Draft M. Chen
Intended status: Standards Track Huawei Technologies
Expires: July 31, 2021 W. Cheng
China Mobile
R. Gandhi
Cisco Systems, Inc.
Q. Xiong
ZTE Corporation
January 27, 2021
Path Computation Element Communication Protocol (PCEP) Extensions for
Associated Bidirectional Segment Routing (SR) Paths
draft-ietf-pce-sr-bidir-path-05
Abstract
The Path Computation Element Communication Protocol (PCEP) provides
mechanisms for Path Computation Elements (PCEs) to perform path
computations in response to Path Computation Clients (PCCs) requests.
Segment routing (SR) leverages the source routing and tunneling
paradigms. The Stateful PCEP extensions allow stateful control of
Segment Routing Traffic Engineering (TE) Paths. Furthermore, PCEP
can be used for computing SR TE paths in the network.
This document defines PCEP extensions for grouping two unidirectional
SR Paths (one in each direction in the network) into a single
Associated Bidirectional SR Path. The mechanisms defined in this
document can also be applied using a Stateful PCE for both PCE-
Initiated and PCC-Initiated LSPs, as well as when using a Stateless
PCE.
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."
Li, et al. Expires July 31, 2021 [Page 1]
Internet-Draft PCEP for Associated Bidirectional SR Paths January 2021
This Internet-Draft will expire on July 31, 2021.
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 . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.1. Requirements Language . . . . . . . . . . . . . . . . . . 4
3. PCEP Extensions . . . . . . . . . . . . . . . . . . . . . . . 5
3.1. Double-sided Bidirectional with Reverse LSP Association . 5
3.1.1. Bidirectional LSP Association Group TLV . . . . . . . 6
4. PCEP Procedures . . . . . . . . . . . . . . . . . . . . . . . 6
4.1. PCE Initiated Associated Bidirectional SR Paths . . . . . 7
4.2. PCC Initiated Associated Bidirectional SR Paths . . . . . 8
4.3. Stateless PCE . . . . . . . . . . . . . . . . . . . . . . 10
4.4. Bidirectional (B) Flag . . . . . . . . . . . . . . . . . 11
4.5. PLSP-ID Usage . . . . . . . . . . . . . . . . . . . . . . 11
4.6. State Synchronization . . . . . . . . . . . . . . . . . . 12
4.7. Error Handling . . . . . . . . . . . . . . . . . . . . . 12
5. Implementation Status . . . . . . . . . . . . . . . . . . . . 12
5.1. Huawei's Commercial Delivery . . . . . . . . . . . . . . 13
5.2. ZTE's Commercial Delivery . . . . . . . . . . . . . . . . 13
6. Security Considerations . . . . . . . . . . . . . . . . . . . 13
7. Manageability Considerations . . . . . . . . . . . . . . . . 13
7.1. Control of Function and Policy . . . . . . . . . . . . . 14
7.2. Information and Data Models . . . . . . . . . . . . . . . 14
7.3. Liveness Detection and Monitoring . . . . . . . . . . . . 14
7.4. Verify Correct Operations . . . . . . . . . . . . . . . . 14
Show full document text