[Docs] [txt|pdf|xml|html] [Tracker] [Email] [Diff1] [Diff2] [Nits]

Versions: 00 01 02 03 04

SIPCORE Working Group                                        C. Holmberg
Internet-Draft                                                  Ericsson
Intended status: Standards Track                                J. Jiang
Expires: December 16, 2013                                  China Mobile
                                                           June 14, 2013


         Via header field parameter to indicate received realm
              draft-holmberg-sipcore-received-realm-01.txt

Abstract

   This specification defines a new Session Initiation Protocol (SIP)
   Via header field parameter, "received-realm", which allows a SIP
   entity acting as an entry point to a transit network to indicate from
   which adjacent upstream network a SIP request is received, using a
   network realm value associated with the adjacent network.

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 http://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."

   This Internet-Draft will expire on December 16, 2013.

Copyright Notice

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












Holmberg & Jiang        Expires December 16, 2013               [Page 1]


Internet-Draft               received realm                    June 2013


   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://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  . . . . . . . . . . . . . . . . . . . . . . . .   2
     1.1.  General . . . . . . . . . . . . . . . . . . . . . . . . .   2
     1.2.  Use-Case: Transit Network Application Services  . . . . .   3
     1.3.  Use-Case: Transit Network Routing . . . . . . . . . . . .   3
   2.  Applicability . . . . . . . . . . . . . . . . . . . . . . . .   4
   3.  Conventions . . . . . . . . . . . . . . . . . . . . . . . . .   4
   4.  Definitions . . . . . . . . . . . . . . . . . . . . . . . . .   4
   5.  User Agent and Proxy behavior . . . . . . . . . . . . . . . .   5
     5.1.  General . . . . . . . . . . . . . . . . . . . . . . . . .   5
     5.2.  Behavior of a SIP entity acting as a network entry point    5
   6.  Examples  . . . . . . . . . . . . . . . . . . . . . . . . . .   5
     6.1.  Example 1 . . . . . . . . . . . . . . . . . . . . . . . .   5
     6.2.  Example 2 . . . . . . . . . . . . . . . . . . . . . . . .   6
   7.  Syntax  . . . . . . . . . . . . . . . . . . . . . . . . . . .   6
     7.1.  General . . . . . . . . . . . . . . . . . . . . . . . . .   6
     7.2.  ABNF  . . . . . . . . . . . . . . . . . . . . . . . . . .   6
   8.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   6
     8.1.  'received-realm' Via header field parameter . . . . . . .   6
   9.  Security Considerations . . . . . . . . . . . . . . . . . . .   6
   10. Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .   7
   11. Change Log  . . . . . . . . . . . . . . . . . . . . . . . . .   7
   12. References  . . . . . . . . . . . . . . . . . . . . . . . . .   7
     12.1.  Normative References . . . . . . . . . . . . . . . . . .   7
     12.2.  Informative References . . . . . . . . . . . . . . . . .   7
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .   7

1.  Introduction

1.1.  General

   When SIP sessions are established between networks belonging to
   different operators, or between interconnected networks belonging to
   the same operator (or enterprise), the SIP requests might traverse
   transit network.





Holmberg & Jiang        Expires December 16, 2013               [Page 2]


Internet-Draft               received realm                    June 2013


   Such transit networks might provide different kind of services.  In
   order to do that, a transit network often needs to know to which
   operator (or enterprise) the adjacent upstream network, from which
   the SIP session initiation request is received, belongs.

   This specification defines a new Session Initiation Protocol (SIP)
   Via header field parameter, "received-realm", which allows a SIP
   entity acting as an entry point to a transit network to indicate from
   which adjacent upstream network a SIP request is received, using a
   network realm value associated with the adjacent network.

   NOTE: As the adjacent network can be an enterprise network, an Inter
   Operator Identifier (IOI) cannot be used to identity the network, as
   IOIs are not defined for enterprise networks.

   The following sections describe use-case where the information is
   needed.

1.2.  Use-Case: Transit Network Application Services

   The 3rd Generation Partnership Project (3GPP) TS 23.228 specifies how
   an IP Multimedia Subsystem (IMS) network can be used to provide
   transit funtionality.  An operator can use its IMS network to provide
   transit functionality e.g. to non-IMS customers, to enterprise
   networks, and to other network operators.

   The transit network operator can provide application services to the
   networks for which it is providing transit functionality.  Transit
   application services are typically not provided per user basis, as
   the transit network does not have access to the user profiles of the
   networks for which the application services are provided.  Instead,
   the application services are provided per served network.

   When a SIP entity that provides application services (e.g. an
   Application Server) within a transit network receives a SIP request,
   in order to apply the correct services it needs to know the adjacent
   upstream network from which the SIP request is received.

1.3.  Use-Case: Transit Network Routing

   A transit network operator normally interconnects to many diferent
   operators, including other transit network operators, and provides
   transit routing of SIP requests received from one operator network
   towards the destination.  The destination can be within an operator
   network to which the transit network operator has a direct
   interconnect, or within an operator network that only can be reached
   via one or more interconnected transit operators.




Holmberg & Jiang        Expires December 16, 2013               [Page 3]


Internet-Draft               received realm                    June 2013


   For each customer, i.e. interconnected network operator for which,
   the transit network operator routes SIP requests towards the
   requested destination a set of transit routing polices are defined.
   These policies are used to determine how a SIP request shall be
   routed towards the requested destination to meet the agreement the
   transit network operator has with its customer.

   When a SIP entity that performs the transit routing functionality
   receives a SIP request, in order to apply the correct set of transit
   routing policies, it needs to know from which of its customers, i.e.
   adjacent upstream network, the SIP request is received.

2.  Applicability

   The mechanism defined in this specification MUST only be used by SIP
   entities that are able to verify from which adjacent upstream network
   a SIP request is received.

   The mechanism for verifying from which adjacent upstream network a
   SIP request is received is outside the scope of this specification.

3.  Conventions

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in BCP 14, RFC 2119
   [RFC2119].

4.  Definitions

   SIP entity: SIP User Agent (UA), or SIP proxy, as defined in RFC
   3261.

   Adjacent upstream SIP network: The adjacent SIP network in the
   direction from which a SIP request is received.

   Network entry point: A SIP entity on the border of network, which
   recieves SIP requests from adjacent upstream networks.

   Inter Operator Identifier (IOI): A globally unique identifier to
   correlate billing information generated within the IP Multimedia
   Subsystem (IMS).









Holmberg & Jiang        Expires December 16, 2013               [Page 4]


Internet-Draft               received realm                    June 2013


5.  User Agent and Proxy behavior

5.1.  General

   This section describes how a SIP entity, acting as an entry point to
   a network, uses the "received-realm" Via header field parameter.

5.2.  Behavior of a SIP entity acting as a network entry point

   When a SIP entity, acting as a network entry point, forwards a SIP
   request, or initiates a SIP request on its own (e.g. a PSTN gateway),
   the SIP entity adds a Via header field to the SIP request, according
   to the procedures in RFC 3261 [RFC3261].  In addition, if the SIP
   entity is able to assert the adjacent upstream network, and if the
   SIP entity is aware of a network realm value defined for that
   network, the SIP entity can add a "received-realm" Via header field
   parameter, conveying the network realm value, to the Via header field
   added to the SIP request.

6.  Examples

6.1.  Example 1

   TBD


   Operator 1       T_EP                                  T_AS

   - INVITE --------->
     Via: IP_UA
                      - INVITE ---------------------------->
                        Via: IP_TEP; received-realm=operator_1.com
                        Via: IP_UA; received=IP_UA

                      <- 200 OK ----------------------------
                         Via: IP_TEP; received-realm=operator_1.co
                         Via: IP_UA; received=IP_UA

   <- 200 OK------
      Via: IP_UA; received=IP_UA











Holmberg & Jiang        Expires December 16, 2013               [Page 5]


Internet-Draft               received realm                    June 2013


6.2.  Example 2

   TBD

7.  Syntax

7.1.  General

   This section describes the syntax extensions to the ABNF syntax
   defined in RFC 3261 [RFC3261], by defining a new Via header field
   parameter, "received-realm".  The ABNF defined in this specification
   is conformant to RFC 5234 [RFC5234].  "EQUAL" and "hostname" are
   defined in RFC 3261 [RFC3261].  "DIGIT" is defined in RFC 5234
   [RFC5234]

7.2.  ABNF

   via-params =/ received-realm

   received-realm = "received-realm" EQUAL hostname



8.  IANA Considerations

8.1.  'received-realm' Via header field parameter

   This specification defines a new Via header field parameter called
   received-realm in the "Header Field Parameters and Parameter Values"
   sub-registry as per the registry created by [RFC3968].  The syntax is
   defined in Section 7.  The required information is:

                                                  Predefined
   Header Field            Parameter Name         Values      Reference
   ----------------------  ---------------------  ----------  ---------
   Via                     received-realm         No          RFCXXXX



9.  Security Considerations

   TBD









Holmberg & Jiang        Expires December 16, 2013               [Page 6]


Internet-Draft               received realm                    June 2013


10.  Acknowledgements

   TBD

11.  Change Log

   [RFC EDITOR NOTE: Please remove this section when publishing]

   Changes from draft-holmberg-received-realm-00

   o  New version due to expiration.

12.  References

12.1.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, March 1997.

   [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.

   [RFC5234]  Crocker, D. and P. Overell, "Augmented BNF for Syntax
              Specifications: ABNF", STD 68, RFC 5234, January 2008.

12.2.  Informative References

   [RFC3968]  Camarillo, G., "The Internet Assigned Number Authority
              (IANA) Header Field Parameter Registry for the Session
              Initiation Protocol (SIP)", BCP 98, RFC 3968, December
              2004.

Authors' Addresses

   Christer Holmberg
   Ericsson
   Hirsalantie 11
   Jorvas  02420
   Finland

   Email: christer.holmberg@ericsson.com








Holmberg & Jiang        Expires December 16, 2013               [Page 7]


Internet-Draft               received realm                    June 2013


   Yi Jiang
   China Mobile
   No.32 Xuanwumen West Street
   Beijing  Xicheng District 100053
   P.R. China

   Email: jiangyi@chinamobile.com












































Holmberg & Jiang        Expires December 16, 2013               [Page 8]


Html markup produced by rfcmarkup 1.129b, available from https://tools.ietf.org/tools/rfcmarkup/