TRENDnet VoIP Gateway, TVP- 221H manual Voice Codecs

TVP-221H User’s Guide

tone to the PSTN. This method in which the TVP-221H handles DTMF tone is so 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.

3.7Voice 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.

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