Specifications

Cisco Unified Survivable Remote Site Telephony Feature Roadmap
Feature Roadmap
9
Cisco Unified Survivable Remote Site Telephony Version 4.0 System Administrator Guide
Call preservation is useful when a gateway and the other endpoint (typically a Cisco Unified IP phone)
are collocated at the same site and the call agent is remote and therefore more likely to experience
connectivity failures.
For configuration information see the “Configuring H.323 Gateways” chapter in the Cisco IOS H.323
Configuration Guide, Release 12.4T at
http://www.cisco.com/univercd/cc/td/doc/product/software/ios123/123cgcr/vvfax_c/callc_c/h323_c/32
3confg/4gwconf.htm.
Video Support
This feature allows you to set video parameters for the Cisco Unified SRST to maintain close feature
parity with Cisco Unified CallManager. When the Cisco Unified SRST is enabled, Cisco Unified IP
Phones do not have to be reconfigured for video capabilities because all ephones retain the same
configuration used with Cisco Unified CallManager. However, you must enter call-manager-fallback
configuration mode to set video parameters for Cisco Unified SRST. The feature set for video is the same
as that for Cisco Unified SRST audio calls.
For more information, see “Setting Video Parameters” chapter of this guide.
Information About New Features in Cisco SRST V3.4
Cisco SRST V3.4 introduced the new features described in the following section:
• SIP SRST, Version 3.4
SIP SRST, Version 3.4
Cisco SIP SRST Version 3.4 describes SRST functionality for Session Initiation Protocol (SIP)
networks. Cisco SIP SRST Version 3.4 provides backup to an external SIP proxy server by providing
basic registrar and back-to-back user agent (B2BUA) services. These services are used by a SIP IP phone
in the event of a WAN connection outage when the SIP phone is unable to communicate with its primary
SIP proxy.
Cisco SIP SRST Version 3.4 can support SIP phones with standard RFC 3261 feature support locally and
across SIP WAN networks. With Cisco SIP SRST Version 3.4, SIP phones can place calls across SIP
networks in the same way as Skinny Client Control Protocol (SCCP) phones. For full information about
SIP SRST, Version 3.4 see the Cisco SIP SRST Version 3.4 System Administrator Guide.
Information About New Features in Cisco SRST V3.3
Cisco SRST V3.3 introduced the new features described in the following sections:
• Secure SRST
• Cisco Unified IP Phone 7970G and Cisco Unified 7971G-GE Support
• Enhancement to the show ephone Command