Trendnet VoIP Gateway User Manual
TVP-221H User’s Guide
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tone to the PSTN. This method in which the TVP-221H handles DTMF tone is so
called DTMF relay.
called DTMF relay.
The TVP-221H handles DTMF relay per H.323 specifications. Certain third party
VoIP devices may handle DTMF relay per IMTC standard. For the TVP-221H to
interoperate with those VoIP devices, users need to specify which remote VoIP
devices uses IMTC conforming DTMF relay technique. Refer to CLI command
Error! Reference source not found. on Chapter 8 for detailed information on how
to select DTMF relay mode.
VoIP devices may handle DTMF relay per IMTC standard. For the TVP-221H to
interoperate with those VoIP devices, users need to specify which remote VoIP
devices uses IMTC conforming DTMF relay technique. Refer to CLI command
Error! Reference source not found. on Chapter 8 for detailed information on how
to select DTMF relay mode.
3.7 Voice
Codecs
Voice codecs supported by the TVP-221H include G.711, G.723.1 5.3kbps,
G.723.1 6.3kbps and G.729 AB. When setting up a call, two VoIP Gateways
automatically negotiate with each other until an agreement on codec is
determined.
G.723.1 6.3kbps and G.729 AB. When setting up a call, two VoIP Gateways
automatically negotiate with each other until an agreement on codec is
determined.