Solutions Fast Track
DSP Provisioning
.. The Cisco DSP module is a Texas Instruments model C542 and C549
72-pin SIMM.These DSPs work with two levels of CODEC
complexity: medium and high.
.. The medium-complexity CODECs that work with the Cisco DSP are
G.711 (a-law and µ-law), G.726, G.729a, G.729ab, and Fax-relay.The
high-complexity CODECs include the G.728, G.723, G.729, G.729b,
and Fax-relay.
.. The DSP resources are used for conference bridging and transcoding.
Conferencing and Transcoding
.. Conferencing is the process of joining multiple callers into a single
multiway call.The two types of multiparticipant voice calls supported by
the Cisco CallManager are ad-hoc and meet-me.
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.. DSP resources are used in the conference bridge scenario to convert
VoIP calls into TDM streams and sum them into a single call.
.. Transcoding is the process of converting IP packets of voice streams
between a low bit-rate (LBR) CODEC to G.711.Transcoding functions
can be done by converting G.723 and G.729 CODECs to G.711.
.. Conferencing and transcoding is performed either by hardware or
software.The software version is performed on a Cisco CallManager
server, while the hardware solutions are the Catalyst 4000 AGM module,
Catalyst 6000 8-port T1/E1Voice and Services module, and NM-HDV
module.