RFC 4028 · PROPOSED STANDARD · 2005

Session Timers in the Session Initiation Protocol

Overview

RFC 4028, “Session Timers in the Session Initiation Protocol”, is a Proposed Standard document published in May 2005 by S. Donovan, J. Rosenberg. The canonical text is published by the RFC Editor.

Abstract

This document defines an extension to the Session Initiation Protocol (SIP). This extension allows for a periodic refresh of SIP sessions through a \%re-INVITE or UPDATE request. The refresh allows both user agents and proxies to determine whether the SIP session is still active. The extension defines two new header fields: \%Session-Expires, which conveys the lifetime of the session, and \%Min-SE, which conveys the minimum allowed value for the session timer. [STANDARDS-TRACK]

Abstract as published in the RFC, via rfc-editor.org.

What “Proposed Standard” means

An entry-level standards-track specification: stable, peer-reviewed and a solid basis for implementation, though it may still evolve before becoming an Internet Standard.

Read this RFC

The canonical text of RFC 4028 is hosted at rfc-editor.org. Available in TXT,HTML.

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