Communications Resource Priority for the Session Initiation Protocol (SIP)
RFC 4412

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>, 
    sip mailing list <sip@ietf.org>, 
    sip chair <sip-chairs@tools.ietf.org>
Subject: Protocol Action: 'Communications Resource Priority for 
         the Session Initiation Protocol (SIP)' to Proposed Standard 

The IESG has approved the following documents:

- 'Extending the Session Initiation Protocol Reason Header for Preemption 
   Events '
   <draft-ietf-sipping-reason-header-for-preemption-05.txt> as a Proposed Standard
- 'Communications Resource Priority for the Session Initiation Protocol 
   (SIP) '
   <draft-ietf-sip-resource-priority-11.txt> as a Proposed Standard

These documents are products of the Session Initiation Protocol Working 
Group. 

The IESG contact persons are Allison Mankin and Jon Peterson.

A URL of this Internet-Draft is:
http://www.ietf.org/internet-drafts/draft-ietf-sip-resource-priority-11.txt

Technical Summary
 
   The resource priority specification defines two new SIP header fields for
   call priority in the SIP user agents, namely "Resource-Priority" and 
   "Accept-Resource-Priority".  The "Resource-Priority" header field can 
   influence call handling by SIP user agents, such as telephone gateways 
   and IP telephones, and SIP proxies.  

   The specification extending the SIP reason header to add preemption
   is a companion to the above specification.  When a call is ended in
   a SIP user agent due to a resource management choice, the extensions
   in this specification allow communicating specific causes.

Working Group Summary
 
 The working group had a fair amount of difficulty getting the
 details of this to its liking, because it had to accomodate
 goals of groups with current requirements, while still leaving
 room for generality.  The solution of independent namespaces
 and reuse of the SIP authorization and authentication mechanisms
 was reviewed and much discussed till consensus was reached.
 The specification received detailed word-by-word review and
 comment until consensus was reached, and it required intensive
 efforts by the chairs and members of the working group, as well
 as the editor and the responsible AD.  
 
Protocol Quality
 
 These headers have been implemented by at least one vendor for
 several namespaces.  In some cases, implemented systems associate
 router resource management with the RP in SIP, somewhat ahead of 
 the scope of IETF design.


Note to the RFC Editor

draft-ietf-sip-resource-priority: 
 OLD:
e.g., in an ISUP IAM message originated by the gateway.

NEW:
e.g., on an ISUP (ISDN User Part) IAM (Initial Address Message) 
originated by a SIP gateway with the PSTN.


OLD:
There should not be a unique namespace for different jurisdictions.
 This will greatly increase interoperability and reduce development
 time, and probably reduce future confusion if there is ever a need
 to map one namespace to another in an interworking function.
 
 NEW:
 There should be a single namespace for all jurisdictions. This will
  greatly increase interoperability and reduce development time, and
  probably reduce future confusion if there is ever a need to map one
  namespace to another in an interworking function.

 [Only the first sentence is changed, for readability]

draft-ietf-sipping-reason-header-for-preemption:

Introduction

OLD:
What is proposed here is extending SIP 

NEW:
What is proposed here is extending SIP [2]
 [add the citation; it's in the Normative References already]