Encoding of Objective Functions in the Path Computation Element Communication Protocol (PCEP)
RFC 5541
| Document | Type |
RFC - Proposed Standard
(June 2009; No errata)
Was draft-ietf-pce-of (pce WG)
|
|
|---|---|---|---|
| Last updated | 2015-10-14 | ||
| Replaces | draft-leroux-pce-of | ||
| Stream | IETF | ||
| Formats | plain text pdf html bibtex | ||
| Reviews | |||
| Stream | WG state | (None) | |
| Document shepherd | No shepherd assigned | ||
| IESG | IESG state | RFC 5541 (Proposed Standard) | |
| Consensus Boilerplate | Unknown | ||
| Telechat date | |||
| Responsible AD | Adrian Farrel | ||
| Send notices to | (None) | ||
Network Working Group JL. Le Roux
Request for Comments: 5541 France Telecom
Category: Standards Track JP. Vasseur
Cisco System Inc.
Y. Lee
Huawei
June 2009
Encoding of Objective Functions in the
Path Computation Element Communication Protocol (PCEP)
Status of This Memo
This document specifies an Internet standards track protocol for the
Internet community, and requests discussion and suggestions for
improvements. Please refer to the current edition of the "Internet
Official Protocol Standards" (STD 1) for the standardization state
and status of this protocol. Distribution of this memo is unlimited.
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Le Roux, et al. Standards Track [Page 1]
RFC 5541 Objective Functions in PCEP June 2009
Abstract
The computation of one or a set of Traffic Engineering Label Switched
Paths (TE LSPs) in MultiProtocol Label Switching (MPLS) and
Generalized MPLS (GMPLS) networks is subject to a set of one or more
specific optimization criteria, referred to as objective functions
(e.g., minimum cost path, widest path, etc.).
In the Path Computation Element (PCE) architecture, a Path
Computation Client (PCC) may want a path to be computed for one or
more TE LSPs according to a specific objective function. Thus, the
PCC needs to instruct the PCE to use the correct objective function.
Furthermore, it is possible that not all PCEs support the same set of
objective functions; therefore, it is useful for the PCC to be able
to automatically discover the set of objective functions supported by
each PCE.
This document defines extensions to the PCE communication Protocol
(PCEP) to allow a PCE to indicate the set of objective functions it
supports. Extensions are also defined so that a PCC can indicate in
a path computation request the required objective function, and a PCE
can report in a path computation reply the objective function that
was used for path computation.
This document defines objective function code types for six objective
functions previously listed in the PCE requirements work, and
provides the definition of four new metric types that apply to a set
of synchronized requests.
Le Roux, et al. Standards Track [Page 2]
RFC 5541 Objective Functions in PCEP June 2009
Table of Contents
1. Introduction ....................................................3
1.1. Conventions Used in This Document ..........................5
1.2. Terminology ................................................5
1.3. Message Formats ............................................6
2. Discovery of PCE Objective Functions ............................6
2.1. OF-List TLV ................................................6
2.2. Elements of Procedure ......................................7
3. Objective Function in PCEP Path Computation Request and Reply
Messages ........................................................7
3.1. OF Object ..................................................7
3.1.1. Elements of Procedure ...............................8
3.2. Carrying The OF Object In a PCEP Message ...................9
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