Specifications

Cisco IOS Survivable Remote Site Telephony Fea ture Roadmap
Feature Roadmap
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Cisco IOS Survivable Remote Site Telephony Version 3.4 System Administrator Guide
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 IOS 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 IP Phone 7970G and Cisco 7971G-GE Support
• Enhancement to the show ephone Command
Secure SRST
Secure Cisco IP phones that are located at remote sites and that are attached to gateway routers can
communicate securely with Cisco CallManager using the WAN. But if the WAN link or Cisco
CallManager goes down, all communication through the remote phones becomes nonsecure. To
overcome this situation, gateway routers can now function in secure SRST mode, which activates when
the WAN link or Cisco CallManager goes down. When the WAN link or Cisco CallManager is restored,
Cisco CallManager resumes secure call-handling capabilities.
Secure SRST provides new SRST security features such as authentication, integrity, and media
encryption. Authentication provides assurance to one party that another party is whom it claims to be.
Integrity provides assurance that the given data has not been altered between the entities. Encryption
implies confidentiality; that is, that no one can read the data except the intended recipient. These security
features allow privacy for SRST voice calls and protect against voice security violations and identity
theft. For more information see the chapter “Setting Up Secure SRST” section on page 97.
Cisco IP Phone 7970G and Cisco 7971G-GE Support
The Cisco IP Phones 7970G and Cisco 7971G-GE are full-featured telephones that provide voice
communication over an IP network. They function much like a traditional analog telephones, allowing
you to place and receive phone calls and to access features such as mute, hold, transfer, speed dial, call
forward, and more. In addition, because the phones are connected to your data network, they offer
enhanced IP telephony features, including access to network information and services, and
customizeable features and services. The phones also support security features that include file
authentication, device authentication, signaling encryption, and media encryption.
The Cisco IP Phones 7970G and Cisco 7971G-GE also provide a color touchscreen, support for up to
eight line or speed-dial numbers, context-sensitive online help for buttons and feature, and a variety of
other sophisticated functions. No configurations specific to SRST are necessary.
For more information, see the following URL:
http://www.cisco.com/univercd/cc/td/doc/product/voice/c_ipphon/english/ipp7970/index.htm
Note The Cisco IP Phone 7914 Expansion Module can attach to your Cisco IP phones 7970G and Cisco
7971G-GE. See Cisco IP Phone Expansion Module 7914 Support, page 17 for more information.