Internet Engineering Task Force (IETF)                        A.B. Roach
Request for Comments: 6878                                       Mozilla
Updates: 3261                                                 March 2013
Category: Standards Track
ISSN: 2070-1721


        IANA Registry for the Session Initiation Protocol (SIP)
                        "Priority" Header Field

Abstract

   This document defines a new IANA registry to keep track of the values
   defined for the Session Initiation Protocol (SIP) "Priority" header
   field.  It updates RFC 3261.

Status of This Memo

   This is an Internet Standards Track document.

   This document is a product of the Internet Engineering Task Force
   (IETF).  It represents the consensus of the IETF community.  It has
   received public review and has been approved for publication by the
   Internet Engineering Steering Group (IESG).  Further information on
   Internet Standards is available in Section 2 of RFC 5741.

   Information about the current status of this document, any errata,
   and how to provide feedback on it may be obtained at
   http://www.rfc-editor.org/info/rfc6878.

Copyright Notice

   Copyright (c) 2013 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

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   described in the Simplified BSD License.

1.  Introduction

   This document defines a new IANA registry to keep track of the values
   defined for the Session Initiation Protocol (SIP) "Priority" header
   field.  This header field was defined in [RFC3261], Section 20.26.
   It was clearly specified in a way that allows for the creation of new
   values beyond those originally specified; however, no registry has
   been established for it.

2.  IANA Considerations

   This document adds a new sub-registry, "Priority Header Field
   Values", to the "Session Initiation Protocol (SIP) Parameters"
   registry page.  Its format and initial values are as shown in the
   following table:

                        +------------+-----------+
                        | Priority   | Reference |
                        +------------+-----------+
                        | non-urgent | RFC 3261  |
                        | normal     | RFC 3261  |
                        | urgent     | RFC 3261  |
                        | emergency  | RFC 3261  |
                        +------------+-----------+

   The policy for registration of values in this registry is "IETF
   Review" as that term is defined by [RFC5226].  This policy was chosen
   over lighter-weight policies due the potential architectural impact
   of the semantics associated with new values.  Efforts contemplating
   adding a Priority value should consider whether the SIP Resource-
   Priority [RFC4412] or even a different protocol would be more
   appropriate for achieving their requirements.

3.  Security Considerations

   This document does not have any impact on the security of the SIP
   protocol.  Its purpose is purely administrative in nature.

4.  References

4.1.  Normative References

   [RFC3261]  Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston,
              A., Peterson, J., Sparks, R., Handley, M., and E.
              Schooler, "SIP: Session Initiation Protocol", RFC 3261,
              June 2002.

   [RFC5226]  Narten, T. and H. Alvestrand, "Guidelines for Writing an
              IANA Considerations Section in RFCs", BCP 26, RFC 5226,
              May 2008.

4.2.  Informative References

   [RFC4412]  Schulzrinne, H. and J. Polk, "Communications Resource
              Priority for the Session Initiation Protocol (SIP)",
              RFC 4412, February 2006.

Author's Address

   Adam Roach
   Mozilla
   Dallas, TX
   US

   EMail: adam@nostrum.com