Specifications

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Chapter 6 Multisite WAN with Distributed Call Processing
DSP Resource Provisioning for Transcoding and Conferencing
Figure 6-17 DSP Resources Across the WAN
The number of allocated resources is based upon the requirements for transcoding
to voice mail as well as transcoding to G.711 for other applications such as
conferencing. These numbers are calculated based upon the ratio of users to voice
mail ports and the volume of conference calls placed.
In an environment where all devices cannot support all codec types, you should
configure dedicated transcoding between clusters. To perform this configuration,
select Device > Gatekeeper in Cisco CallManager Administration and enable the
Media Termination Point Required checkbox. If you do not perform this
Region A
Call setup to
Cisco CallManager A
or 666-1212
Set up RTP stream to
Cisco CallManager
DSP farm
IP WAN
G.711 only
555-1212
dials
666-1212
MTP
MTP
B
666-1212
Router/GW
Router/GW
Intraregion
A=G.711
Interregion
A to B
G.729
Region B
Intraregion
B=G.711
Interregion
B to A
G.729
MTP
G.711 call leg
Compresses call leg
Transcoding
resources
=
IP
IP IP
IP
G.711 only
40809