4. Disconnect Tone Configuration
This application note is going to describe the procedures of configuring the disconnect tone on VoIP FXO gateway in order to release LINE ports of VoIP FXO gateway after PSTN/PBX caller party is hung up.
4.1 What is Disconnect Tone
IP Side
VoIP
FXO gateway
PSTN side | PSTN or | |
PBX | ||
|
Other VoIP devices
Caller
A caller make a telephone call to gateway from PSTN side, VoIP FXO gateway will answer the call automatically. If the IP side of other VoIP devices do not answer the call and the caller hang up the call, the PSTN/PBX will give gateway a disconnect tone automatically. Or, VoIP FXO gateways are installed on both sied and connect to local PSTN. If both parties are in talking mode and one side hang up the call. the VoIP FXO gateway has to recognize the disconnect tone from local PSTN and release the line port with the
There are three parameters received from PSTN/PBX.
-High level frequency and Low level frequency
-Tone Cadence (ON/OFF intervals)
-Tone level
These parameters have to be properly configured in VoIP FXO gateway in order to recognize disconnect tone correctly. Each different PSTN/PBX have different parameters. So, VoIP FXO gateway has to configure tone table when line port connect to different PSTN/PBX.
4.2 How to configure disconnect tone on VoIP FXO gateway
VoIP FXO gateway has a default setting of disconnect tone (Busy tone 1, Busy tone 2, reorder tone 1 and reorder tone 2 ). If the disconnect tone was recognized correctly, the line port from PSTN/PBX will be released in seconds.
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