Session Initiation Protocol (SIP) Basic Call Flow Examples
RFC 3665
| Document | Type |
RFC - Best Current Practice
(January 2004; Errata)
Also known as BCP 75
|
|
|---|---|---|---|
| Last updated | 2020-01-21 | ||
| Stream | IETF | ||
| Formats | plain text html pdf htmlized with errata bibtex | ||
| Stream | WG state | (None) | |
| Document shepherd | No shepherd assigned | ||
| IESG | IESG state | RFC 3665 (Best Current Practice) | |
| Consensus Boilerplate | Unknown | ||
| Telechat date | |||
| Responsible AD | Allison Mankin | ||
| IESG note | All Discusses resolved 2003-06-17. | ||
| Send notices to | <rohan@cisco.com>, <dean.willis@softarmor.com> | ||
Network Working Group A. Johnston
Request for Comments: 3665 MCI
BCP: 75 S. Donovan
Category: Best Current Practice R. Sparks
C. Cunningham
dynamicsoft
K. Summers
Sonus
December 2003
Session Initiation Protocol (SIP) Basic Call Flow Examples
Status of this Memo
This document specifies an Internet Best Current Practices for the
Internet Community, and requests discussion and suggestions for
improvements. Distribution of this memo is unlimited.
Copyright Notice
Copyright (C) The Internet Society (2003). All Rights Reserved.
Abstract
This document gives examples of Session Initiation Protocol (SIP)
call flows. Elements in these call flows include SIP User Agents and
Clients, SIP Proxy and Redirect Servers. Scenarios include SIP
Registration and SIP session establishment. Call flow diagrams and
message details are shown.
Johnston, et al. Best Current Practice [Page 1]
RFC 3665 SIP Basic Call Flow Examples December 2003
Table of Contents
1. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. General Assumptions. . . . . . . . . . . . . . . . . . . 3
1.2. Legend for Message Flows . . . . . . . . . . . . . . . . 3
1.3. SIP Protocol Assumptions . . . . . . . . . . . . . . . . 4
2. SIP Registration . . . . . . . . . . . . . . . . . . . . . . . 4
2.1. Successful New Registration. . . . . . . . . . . . . . . 5
2.2. Update of Contact List . . . . . . . . . . . . . . . . . 7
2.3. Request for Current Contact List . . . . . . . . . . . . 8
2.4. Cancellation of Registration . . . . . . . . . . . . . . 9
2.5. Unsuccessful Registration. . . . . . . . . . . . . . . . 10
3. SIP Session Establishment. . . . . . . . . . . . . . . . . . . 12
3.1. Successful Session Establishment . . . . . . . . . . . . 12
3.2. Session Establishment Through Two Proxies. . . . . . . . 15
3.3. Session with Multiple Proxy Authentication . . . . . . . 26
3.4. Successful Session with Proxy Failure. . . . . . . . . . 37
3.5. Session Through a SIP ALG. . . . . . . . . . . . . . . . 46
3.6. Session via Redirect and Proxy Servers with SDP in ACK . 54
3.7. Session with re-INVITE (IP Address Change) . . . . . . . 61
3.8. Unsuccessful No Answer . . . . . . . . . . . . . . . . . 67
3.9. Unsuccessful Busy. . . . . . . . . . . . . . . . . . . . 75
3.10. Unsuccessful No Response from User Agent . . . . . . . . 80
3.11. Unsuccessful Temporarily Unavailable . . . . . . . . . . 85
4. Security Considerations. . . . . . . . . . . . . . . . . . . . 91
5. References . . . . . . . . . . . . . . . . . . . . . . . . . . 91
5.1. Normative References . . . . . . . . . . . . . . . . . . 91
5.2. Informative References . . . . . . . . . . . . . . . . . 91
6. Intellectual Property Statement. . . . . . . . . . . . . . . . 91
7. Acknowledgments. . . . . . . . . . . . . . . . . . . . . . . . 92
8. Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . 93
9. Full Copyright Statement . . . . . . . . . . . . . . . . . . . 94
1. Overview
The call flows shown in this document were developed in the design of
a SIP IP communications network. They represent an example minimum
set of functionality.
It is the hope of the authors that this document will be useful for
SIP implementers, designers, and protocol researchers alike and will
help further the goal of a standard implementation of RFC 3261 [1].
These flows represent carefully checked and working group reviewed
scenarios of the most basic examples as a companion to the
specifications.
Johnston, et al. Best Current Practice [Page 2]
RFC 3665 SIP Basic Call Flow Examples December 2003
These call flows are based on the current version 2.0 of SIP in RFC
3261 [1] with SDP usage described in RFC 3264 [2]. Other RFCs also
comprise the SIP standard but are not used in this set of basic call
flows.
Call flow examples of SIP interworking with the PSTN through gateways
are contained in a companion document, RFC 3666 [5].
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 [4].
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