Information About Configuring Sip Srst Features Using Back-To-Back User Agent Mode; Cisco Unified Sip Srst And Cisco Sip Communications Manager Express Feature Crossover - Cisco CP-7911G-CH1 System Administrator Manual

Configuring Call Handling
Information About Configuring SIP SRST Features Using
Back-to-Back User Agent Mode
A Cisco Unified SRST system can now support SIP phones with standard-based RFC 3261 feature
support locally and across SIP WAN networks. With Cisco Unified SIP SRST, SIP phones can place calls
across SIP networks with similar features, as SCCP phones do. For example, most SCCP phone features
such as caller ID, speed dial, and redial are supported now on SIP networks, which gives users the
opportunity to choose SCCP or SIP.
Cisco Unified SIP SRST also uses a back-to-back user agent (B2BUA), which is a separate call agent
that has more features than Cisco SIP SRST 3.0, which used a redirect server that only accepted and
forwarded calls. The main advantage of a B2BUA call agent is in call forwarding, because it forwards
calls on behalf of the phone. In addition, it maintains a presence as call middleman in the call path.
Cisco SIP SRST 3.4 supports the following call combinations:
•
•
•
Cisco Unified SIP SRST and Cisco SIP Communications Manager Express
Feature Crossover
The voice regisiter dn, voice register global and voice register pool configuration mode commands are
accessible in both Cisco Unified SIP CME and Cisco Unified SIP SRST modes of operation. However,
not all of the commands within these modes are intended for use in SIP SRST mode.
summary guide to which commands are relevant to the CME or SRST modes of operation.
For more detailed information, refer to the command reference pages for each of the individual
commands.
Table 1
Note
Table 1
Command
after-hour exempt X
auto-answer
call forward
huntstop
label
name
number
OL-13143-04
SIP phone to SIP phone
SIP phone to PSTN / router voice port
SIP phone to SCCP phone
is not all-inclusive; additional commands may exist.
Version 3.4 New or Enhanced Commands for Cisco Unified SRST and Cisco Unified
CME (Sorted by Configuration Mode)
Dial
Peer
—
X
X
—
—
X

Information About Configuring SIP SRST Features Using Back-to-Back User Agent Mode

Configurable for 
Voice
Register Cisco Unified (SIP ) CME
Mode and Cisco Unified SIP SRST
dn X
dn —
dn X
dn X
dn —
dn —
dn X
Cisco Unified SCCP and SIP SRST System Administrator Guide
Table 1 provides a
Applicable to 
Cisco Unified (SIP) CME Only
—
X
—
—
X
X
—
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