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SIP User Agent Redundancy

Overview

The SIP software supports redundancy allowing the SIP UA to continue functioning after a CSP Matrix Series 3 Card switchover.

In an CSP with redundant CSP Matrix Series 3 Cards, the cards themselves are physically identical.

Important! To enable SIP UA Redundancy, you must configure a shared IP address. The shared IP address is for redundancy only. All API message should be sent directly to the active matrix card’s IP address - not to the shared IP address.

Description

All communication to the CSP Matrix Series 3 Cards are over this one shared IP address. You create this shared IP configuration using DHCP or BOOTP. See Redundant CSP Matrix Series 3 Card in the API Developer’s Guide: Overview for general information about redundancy on the CSP Matrix Series 3 Card.

The two matrix cards communicate with each other over a High-Level Data Link Control (HDLC) link. The SIP software data structures are dynamically updated from the active CSP Matrix Series 3 Card to the standby CSP Matrix Series 3 Card on this midplane bus so calls in the connected or answered state are maintained during a switchover. Calls in transition are dropped.

Figure 5-4 SIP UA Redundancy

Configuring

See either of the following two procedures in the Application Development chapter of the Developer’s Guide: Overview to set up the shared IP address:

Configuring a Shared IP Address Using BOOTP Server

Configuring a Shared IP Address Using DHCP Server

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.
Internet Protocol. Part of the TCP/IP family of protocols used to route messages and tracks the addresses of nodes.
Dynamic Host Controlled Protocol
Boot protocol for TCP/IP
HDLC. A bit oriented communication protocol where control codes differ according to their bit positions and pattern.
A 32-bit address, used in IP routing, which includes a Network address identifier assigned by a central authority and a Host ID (an end station identifier assigned by a LAN administrator).