Hunt group table, Destination table, 6 dtmf relay – TRENDnet TVP-224HR User Manual

Page 63: Dtmf relay

Advertising
background image

TVP-224HR User’s Guide

63

• Address table sample:

Address
Entry

Hunt
Grp_Id

Min.
Digits

Max. Digits Prefix

strip

Prefix
Address

201 3 3

3 3

None

301 4 3

3 3

None

8 1

3

3

0

None

0 1

1

1

0

None

20 11

5

5 2

None

Hunt Group Table

The hunt group table maps a hunt group to a list of destinations. Hunt group
sample

Hunt Group ID

Hunt Type

# of Dest ID(s)

Dest. ID(s)

1 2 1 1
3 2 1 3
4 2 1 4

11 2 1 11

Destination Table

The destination table maps a destination to a telephony port or the IP address of a
remote TVP-224HR.

Destination table sample

Dest ID

Mode

Destination

1

Local

Port = 0

3

Local

Port = 2

4

Local

Port = 3

11

H.323

Dest = 192.168.0.55/1720 TCP

8.6 DTMF

Relay

Voice from PSTN is compressed by the TVP-224HR before it is sent across the IP
network and then decompressed by the destination VoIP gateway. The voice
codecs supported by the TVP-224HR are designed for ideally compressing and
decompressing human voice. If the compression / decompression process is
performed on DTMF tone which needs to be conveyed across IP network,
distortion might be too significant to be cognizable on the receiving end. To
overcome the shortcoming that the voice codecs may have encoding DTMF tone,
the TVP-224HR encodes DTMF tone into special packets. The packets are then
sent to the destination VoIP Gateway via a separate IP connection. The destination
VoIP Gateway decodes the packets, generates the DTMF tone, and then sends the

Advertising