analog DID on MGCP FXO port

t-alkhalidi · ‎05-29-2008

can we have analog DID service on 2821 MGCP gateway with call manager 5? what is mean of unattended port? still confused about .

jechoi · ‎05-29-2008

Unattended port is like connection plar on voice-port. you put the DN where you want the call to be forwarded to.

FXO, no DID. when caller calls, fxo answers and waiting for caller to enter a digit without caller hearing anything. Thus the reason we normally use connection plar to route the call to IVR or an operator.

pcameron · ‎06-01-2008

Analogue DID in the 'traditional' sense uses the DID voice card. The DID card is actually a FXS interface that provides a battery feed towards the telephone exchance, but it uses battery (line polarity) reversal to signal the call based on E&M call states (can be immediate start or wink start). When a call comes from the exchange towards the voice card, the exchange causes a polarity reversal to indicate a call seize. The voice port then reverses the polarity for 200msec (as a wink) to indicate the card is ready to accept digits. When the exchange gets the wink from the voice card, the exchange then sends the digits as in band DTMF tones.

At the moment, Call Manager MGCP does not support any form of analogue DID operation - it only works for H323 or SIP call control.

It also means that you cannot use a FXO card for analogue DID services.

Hope this clarifies things.