A dial plan is a set of dial patterns that SIP phones use to determine when a digit collection is complete after you go off-hook
and dial a destination number. Dial plans enable SIP phones to perform local digit collection and recognize dial patterns
that you have keyed. After a pattern is recognized, the SIP phone sends an INVITE message to Cisco Unified SRST to initiate
the call to the number matching your input. All the digits entered by the user are presented as a block to Cisco Unified SRST
for processing. Because digit collection is done by the phone, dial plans reduce signaling messages overhead compared to KPML
digit collection.
SIP dial plans eliminate the need for a user to press the Dial softkey or # key or to wait for the interdigit timeout to trigger
an outgoing INVITE. You configure a SIP dial plan and associate the dial plan with a SIP phone. The dial plan is downloaded
to the phone in the configuration file.
You can configure SIP dial plans and associate them with the following SIP phones:
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Cisco Unified IP Phone 7911G, 7941G, 7941GE, 7961G, 7961GE, 7970G, and 7971GE: These phones use dial plans and support KPML.
If both a dial plan and KPML are enabled, the dial plan has priority.
If a matching dial plan is not found and KPML is disabled, the user must wait for the interdigit timeout before the SIP NOTIFY
message is sent to Cisco Unified SRST. Unlike other SIP phones, these phones do not have a Dial softkey to indicate the end
of dialing, except when on-hook dialing is used.
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Cisco Unified IP Phone 7905, 7912, 7940, and 7960: These phones use dial plans and do not support KPML. If you do not configure
a SIP dial plan for these phones, or if the dialed digits do not match a dial plan, the user must press the Dial softkey or
wait for the interdigit timeout before digits are sent to Cisco Unified SRST for processing.
When you reset a phone, the phone requests its configuration files from the TFTP server, which builds the appropriate configuration
files depending on the type of phone.
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Cisco Unified IP Phone 7905 and 7912: The dial plan is a field in their configuration files.
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Cisco Unified IP Phone 7911G, 7940, 7941G, 7941GE, 7960, 7961G, 7961GE, 7970G, and 7971GE: The dial plan is a separate XML
file that is pointed to from the normal configuration file.
The Cisco Unified SRST supports SIP dial plans if they are provisioned in Cisco Unified Communications Manager. You cannot
configure dial plans in Cisco Unified SRST.