Path Computation Element Communication Protocol (PCEP) Requirements and Protocol Extensions in Support of Global Concurrent Optimization
RFC 5557

Approval announcement
Draft of message to be sent after approval:

From: The IESG <iesg-secretary@ietf.org>
To: IETF-Announce <ietf-announce@ietf.org>
Cc: Internet Architecture Board <iab@iab.org>,
    RFC Editor <rfc-editor@rfc-editor.org>, 
    pce mailing list <pce@ietf.org>, 
    pce chair <pce-chairs@tools.ietf.org>
Subject: Protocol Action: 'Path Computation Element 
         Communication Protocol (PCEP) Requirements and Protocol 
         Extensions In Support of Global Concurrent Optimization' to 
         Proposed Standard 

The IESG has approved the following document:

- 'Path Computation Element Communication Protocol (PCEP) Requirements 
   and Protocol Extensions In Support of Global Concurrent Optimization '
   <draft-ietf-pce-global-concurrent-optimization-10.txt> as a Proposed Standard

This document is the product of the Path Computation Element Working 
Group. 

The IESG contact persons are Ross Callon and Adrian Farrel.

A URL of this Internet-Draft is:
http://www.ietf.org/internet-drafts/draft-ietf-pce-global-concurrent-optimization-10.txt

Technical Summary

   The Path Computation Element (PCE) is a network component,
   application, or node that is capable of performing path computations
   at the request of Path Computation Clients (PCCs). When computing
   or re-optimizing the routes of a set of TE LSPs
   through a network it may be advantageous to perform bulk path
   computations in order to avoid blocking problems and to achieve more
   optimal network-wide solutions.  Such bulk optimization is termed
   Global Concurrent Optimization (GCO).  A GCO is able to
   simultaneously consider the entire topology of the network and the
   complete set of existing TE LSPs, and their respective constraints,
   and look to optimize or re-optimize the entire network to satisfy all
   constraints for all TE LSPs.  A GCO may also be applied to some
   subset of the TE LSPs in a network.  The GCO application is primarily
   a Network Management System (NMS) solution.

   This document provides application-specific requirements and the PCEP
   extensions in support of GCO applications.

Working Group Summary

   The WG has good consensus with no disputes or disagreements.
   Concerns over the impact of this work on network stability (as
   a result of "churn") have been addressed with suitable text 
   added to describe the concerns and advise the operator about
   the associated risk (see PROTO writeup by Adrian Farrel).

Document Quality

   There are two known implementations of the protocol extensions 
   described in this document. The document has been updated in
   response to comments from WG discussions and IETF last call, as 
   well as Gen-Art review and in response to IANA questions. 

Personnel

   Adrian Farrel is the Document Shepherd for this document. Ross
   Callon is the Responsible Area Director.  

RFC Editor Note

  Section 5.5, Please delete the one-sentence paragraph which 
  currently reads: 

    Reserved bits (24 bits) of the GLOBAL CONSTRAINTS Object SHOULD
    be transmitted as zero and SHOULD be ignored upon receipt.

  Section 5.5, Please update the following text: 

  OLD
    MU (Max Utilization Percentage: 8 bits) : 8 bits integer that
    indicates the upper bound utilization percentage by which all link
    should be bound.  Utilization = (Link Capacity - Allocated Bandwidth
    on the Link)/ Link Capacity 

  NEW
    MU (Max Utilization Percentage: 8 bits) : 8 bits integer that
    indicates the upper bound utilization percentage by which all link
    should be bound.  Utilization = (Link Capacity - Allocated Bandwidth
    on the Link)/ Link Capacity. MU is intended to be integer that can
    only be between 0 and 100.

  OLD
    mU (minimum Utilization Percentage: 8 bits) : 8 bits integer that
    indicates the lower bound utilization percentage by which all link
    should be bound.

  NEW
    mU (minimum Utilization Percentage: 8 bits) : 8 bits integer that
    indicates the lower bound utilization percentage by which all link
    should be bound. mU is intended to be integer that can only be 
    between 0 and 100.

  Throughout Section 4 and Section 5 (several places) Please update
  the following reference:

  OLD
    [PCEP]

  NEW
    [RFC5440]