Browse Prior Art Database

Requirements for Management of Overload in the Session Initiation Protocol (RFC5390)

IP.com Disclosure Number: IPCOM000177363D
Original Publication Date: 2008-Dec-01
Included in the Prior Art Database: 2008-Dec-10
Document File: 15 page(s) / 33K

Publishing Venue

Internet Society Requests For Comment (RFCs)

Related People

J. Rosenberg: AUTHOR

Abstract

Overload occurs in Session Initiation Protocol (SIP) networks when proxies and user agents have insufficient resources to complete the processing of a request. SIP provides limited support for overload handling through its 503 response code, which tells an upstream element that it is overloaded. However, numerous problems have been identified with this mechanism. This document summarizes the problems with the existing 503 mechanism, and provides some requirements for a solution.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 8% of the total text.

Network Working Group                                       J. Rosenberg Request for Comments: 5390                                         Cisco Category: Informational                                    December 2008

              Requirements for Management of Overload in the                       Session Initiation Protocol

Status of This Memo

   This memo provides information for the Internet community.  It does    not specify an Internet standard of any kind.  Distribution of this    memo is unlimited.

Copyright Notice

   Copyright (c) 2008 IETF Trust and the persons identified as the    document authors.  All rights reserved.

   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.

Abstract

   Overload occurs in Session Initiation Protocol (SIP) networks when    proxies and user agents have insufficient resources to complete the    processing of a request.  SIP provides limited support for overload    handling through its 503 response code, which tells an upstream    element that it is overloaded.  However, numerous problems have been    identified with this mechanism.  This document summarizes the    problems with the existing 503 mechanism, and provides some    requirements for a solution.

 Rosenberg                    Informational                      [Page 1]
 RFC 5390                 Overload Requirements             December 2008

 Table of Contents

   1. Introduction ....................................................2

   2. Causes of Overload ..............................................2

   3. Terminology .....................................................4

   4. Current SIP Mechanisms ..........................................4

   5. Problems with the Mechanism .....................................5

      5.1. Load Amplification .........................................5

      5.2. Underutilization ...........................................9

      5.3. The Off/On Retry-After Problem .............................9

      5.4. Ambiguous Usages ..........................................10

   6. Solution Requirements ..........................................10

   7. Security Considerations ........................................13

   8. Acknowledgements ...............................................13

   9. References .....................................................14

      9.1. Normative Ref...