Cisco Survivable Remote Site Telephony (SRST) for Cisco IAD 2400, 1751, 1760, 2600, 3620 Routers

As enterprises extend their IP telephony and high-value application deployments from central sites out to remote offices, one of the factors considered vital in deployment is the ability to cost-effectively provide backup redundancy functions at the remote branch office. However, the size and number of these small-office sites precludes most enterprises from deploying dedicated call-processing servers, unified messaging servers, or multiple WAN links to each site to achieve the high availability required. The Cisco IP Communications Solution utilizes Cisco CallManager in combination with a feature called Survivable Remote Site Telephony (SRST) in Cisco IOS software to enable companies to extend high-availability IP telephony to their small branch offices. The Cisco SRST solution provides a rich feature set in back-up mode and is a cost-effective solution that is extremely simple to deploy, administer, and maintain.