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SIP/VoIP Media Parameters Synchronization

Overview

The SIP/VoIP Media Parameters Synchronization feature provides a way to maintain SIP signaling in synchronization with the parameters on the following cards:

• VDAC-ONE

• IP Network Interface Series 2

Description

Prior to this feature, the IP Signaling Layer 3 protocol, SIP, maintained a locally cached copy of VoIP media parameters on a per-module basis. When the VoIP media cards are reconfigured through the Resource Attribute Configure (0x00E3) message, the local copy of configuration data maintained by SIP on the CSP Matrix Series 3 Card remains unchanged. In this way, the SIP and VoIP media parameters become unsynchronized.

The SIP stack needs to maintain an up-to-date, locally cached copy of VoIP media parameters in order to stay in synchronization with the VoIP media parameters.

Configuring

In order to do so, the host application initiates the SIP stack configuration message, VoIP Protocol Configure (0x00EE) with the Resynchronize VoIP Media Parameters TLV (0x0284). This TLV enables the SIP stack to resynchronize with all the VoIP modules that have been previously cached by the SIP stack. For the details of this TLV, refer to the API Reference.

Example:

Below is an example of the VoIP Protocol Configure message with the Resynchronize VoIP Media Parameters TLV (0x0284) sent by the host application to ensure SIP and VoIP media parameter synchronization.

00 14 00 EE 00 00 FF 00 00 00 00 02 01 C8 00 01 04 02 84 00 01 01

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).
Internet Protocol. Part of the TCP/IP family of protocols used to route messages and tracks the addresses of nodes.
Protocol layer of the CSP.
Tag-Length-Value block. A standardized block that allows data to inserted in a standard way into API messages.