Network Working Group D. Willis
Request for Comments: 3608 dynamicsoft Inc.
Category: Standards Track B. Hoeneisen
Switch
October 2003
Session Initiation Protocol (SIP) Extension Header Field
for Service Route Discovery During Registration
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.
Copyright Notice
Copyright (C) The Internet Society (2003). All Rights Reserved.
Abstract
This document defines a Session Initiation Protocol (SIP) extension
header field used in conjunction with responses to REGISTER requests
to provide a mechanism by which a registrar may inform a registering
user agent (UA) of a service route that the UA may use to request
outbound services from the registrar's domain.
Table of Contents
1. Terminology . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Background . . . . . . . . . . . . . . . . . . . . . . . . . 2
3. Discussion of Mechanism . . . . . . . . . . . . . . . . . . 4
4. Applicability Statement . . . . . . . . . . . . . . . . . . 5
5. Syntax . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
6. Usage . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
6.1. Procedures at the UA . . . . . . . . . . . . . . . . . 6
6.2. Procedures at the Proxy . . . . . . . . . . . . . . . 7
6.3. Procedures at the Registrar . . . . . . . . . . . . . 8
6.4. Examples of Usage . . . . . . . . . . . . . . . . . . 9
6.4.1. Example of Mechanism in REGISTER Transaction . 9
6.4.2. Example of Mechanism in INVITE Transaction . . 12
7. Security Considerations . . . . . . . . . . . . . . . . . . 14
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . 15
9. Normative References . . . . . . . . . . . . . . . . . . . . 15
10. Informative References . . . . . . . . . . . . . . . . . . . 15
Willis & Hoeneisen Standards Track