Specifications

Cisco Unified SIP SRST Feature Overview

Support for Cisco Unified IP Phones and Platforms

Cisco Unified SIP SRST 4.0 System Administrator Guide

Figure 2 Call Proceeds with Cisco Unified SIP SRST, When WAN Is Down

Support for Cisco Unified IP Phones and Platforms

The following sections provide information about Cisco Feature Navigator and the histories of

Cisco Unified IP Phone and platform support from Cisco SRST 3.0 to the present version.

• Finding Cisco IOS Software Releases That Support Cisco Unified SRST, page 7

• Cisco Unified IP Phone Support, page 8

• Platform and Memory Support, page 8

Finding Cisco IOS Software Releases That Support Cisco Unified SRST

The tables in this chapter list only the Cisco IOS software releases that first introduce new features to

Cisco Unified SRST. Other Cisco IOS software releases may subsequently inherit versions of

Cisco Unified SRST. To get a list of Cisco IOS software releases that support a particular version of

Cisco Unified SRST, use Cisco Feature Navigator.

Cisco Feature Navigator is a web-based tool that enables you to determine which Cisco IOS software

images support a specific set of features and which features are supported in a specific Cisco IOS image.

You can search by feature or release. Under the release section, you can compare releases side by side

to display both the features unique to each software release and the features in common.

To access Cisco Feature Navigator, you must have an account on Cisco.com. If you have forgotten or

lost your account information, send a blank e-mail to cco-locksmith@cisco.com. An automatic check

will verify that your e-mail address is registered with Cisco.com. If the check is successful, account

details with a new random password will be e-mailed to you. Qualified users can establish an account

on Cisco.com by following the directions found at this URL:

http://tools.cisco.com/RPF/register/register.do

Cisco Feature Navigator is updated regularly when major Cisco IOS software releases and technology

releases occur. For the most current information, go to the Cisco Feature Navigator home page at the

following URL:

http://www.cisco.com/go/fn

146133

SIP proxy server

WAN

PSTN

SIP phone

SIP SRST registrar

(B2BUA router)

Dual registration