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Dial Tone issues


We have CCM 3.3(3).

We have 3640 router(IOS-12.1(5)T9) with 8 port FXS(Connected to PBX)card at the remote end.

Route pattern on ccm is 4.!#.

H323 gateway is configured on CCM for the remote router.I have configured dial peer VOIP pointing to CCM with destination pattern 20.. (IP phones at local end range 2001-2099)

4 FXS Ports on the router is configured with destination pattern as 5001(Hunting) connected to a PBX.

Problem-1.When I press 4,I am not getting any dial tone but immediately when I press any other second digit,I get the dial tone.

2.Also when I continuosly press 45001,I can hear a ring back followed by a dial tone but cannot dial any other remote extension connected to the PBX.

I get ring back only when I dial 45001 or else I get fast busy tone.There is no overlapping dial plan.

I tried configuring H323 gateway on a 3640 local(LAN) router with four port FXS card.I am getting a proper dial tone& am able to communicate with an analog phone connected to an FXS port.

Query-1Why am I not getting dial tone when I press 4 for the remote gateway. Why I am getting dial tone only when I press any second digit.

2.Kindly suggest the config for remote end router.




Re: Dial Tone issues

You have a conflict with the route patter 4.!# and either another route pattern on an extension. The CM won't giver the second dial tone unless it can differentiate between the 2 numbers.

FXS ports don't normally send digits. They are designed to plug handsets int, and there was no foreseen reason to send a string of DTMF digits towards an on hook phone that is still ring. They are not the ideal way of trunking to a PBX.

That said, more recent versions of IOS will allow FXS ports to send digits out.

Remember that a POTS dial peer will strip any explicitly matched digits on the destination pattern, so you may need to reconfigure the destination pattern to use wildcard matching or use the foward-digits command to send the digits out.

However, this then assumes the PBX has special DID cards on it to actually receive the digits that the router sends. If it doesn't you will send the digits into a PBX trunk that will simply ignore them - it is more interested in the fact the FXS port is sending a 80VAC ring signal.

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