Browse Prior Art Database

The Session Initiation Protocol (SIP) Refer Method (RFC3515)

IP.com Disclosure Number: IPCOM000012127D
Original Publication Date: 2003-Apr-01
Included in the Prior Art Database: 2003-Apr-10
Document File: 24 page(s) / 48K

Publishing Venue

Internet Society Requests For Comment (RFCs)

Related People

R. Sparks: AUTHOR

Abstract

This document defines the REFER method. This Session Initiation Protocol (SIP) extension requests that the recipient REFER to a resource provided in the request. It provides a mechanism allowing the party sending the REFER to be notified of the outcome of the referenced request. This can be used to enable many applications, including call transfer.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 6% of the total text.

Network Working Group� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � R. Sparks

Request for Comments: 3515� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � dynamicsoft

Category: Standards Track� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � April 2003

� � � � � � � � � � The Session Initiation Protocol (SIP) Refer Method

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 the REFER method.� This Session Initiation

� � Protocol (SIP) extension requests that the recipient REFER to a

� � resource provided in the request.� It provides a mechanism allowing

� � the party sending the REFER to be notified of the outcome of the

� � referenced request.� This can be used to enable many applications,

� � including call transfer.

� � In addition to the REFER method, this document defines the the refer

� � event package and the Refer-To request header.

Table of Contents

� � 1.� Overview . . . . . . . . . . . . . . . . . . . . . . . . . .� 2

� � 2.� The REFER Method . . . . . . . . . . . . . . . . . . . . . .� 3

� � � � � � 2.1� The Refer-To Header Field . . . . . . . . . . . . . . .� 3

� � � � � � 2.2� Header Field Support for the REFER Method . . . . . . .� 4

� � � � � � 2.3� Message Body Inclusion. . . . . . . . . . . . . . . . .� 5

� � � � � � 2.4� Behavior of SIP User Agents . . . . . . . . . . . . . .� 6

� � � � � � � � � � � 2.4.1 Forming a REFER request . . . . . . . . . . . . .� 6

� � � � � � � � � � � 2.4.2 Processing a REFER request. . . . . . . . . . . .� 6

� � � � � � � � � � � 2.4.3 Accessing the Referred-to Resource. . . . . . . .� 6

� � � � � � � � � � � 2.4.4 Using SIP Events to Report the Results

� � � � � � � � � � � � � � � � � of the Reference. . . . . . . . . . . . . . . . .� 7

� � � � � � � � � � � 2.4.5 The Body of the NOTIFY. . . . . . . . . . . . . .� 8

� � � � � � � � � � � 2.4.6 Multiple REFER Requests in a Dialog . . . . . . .� 9

� � � � � � � � � � � 2.4.7 Using the Subscription-State Header

� � � � � � � � � � � � � � � � � Field with Event Refer. . . . . . . . . . . . . .� 9

Sparks� � � � � � � � � � � � � � � � � � � � � Standards Track� � � � � � � � � � � � � � � � � � � � [Page 1]

RFC 3515� � � � � � � � � � � � � � � � � The SIP Refer Method� � � � � � � � � � � � � � � April 2003

� � � � � � 2.5� Behavior of SIP Registrars/Redirect Servers . . . . . .� 9

� � � � � � 2.6� Behavior of SIP Proxies . . . . . . . . . . . . . . . . 10

� � 3.� Package Details: Event refer . . . . . . . . . . . . . . . . 10

� � � �...