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Session Timers

Overview

SIP Session Timers are an extension of SIP RFC 2543 which allows a periodic refreshing of SIP sessions using the RE-INVITE message. The refreshing allows both user agents and proxies to determine if the SIP session is still active.

In addition, the SIP software supports response code 422.
Responses in the SIP Support and Compliance Appendix.

Pertinent Specification

RFC 2543/4028

Configuring

Use the following TLVs in the VoIP Protocol Configure (0x00EE) message to implement this feature:

• 0x027C Min-SE Interval

• 0x027B Session Interval

Session-Initiation Protocol. A signaling protocol used for establishing sessions in an IP network. A session could be a simple, two-way telephone call, or it could be a collaborative multi-media conference session.
Voice over Internet Protocol. The delivery of voice information in digital form in discrete packets rather than in the traditional circuit-committed protocols of the public-switched telephone network (PSTN).