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some VOIP problem_ pls help

I have setup 3 voice gateway router to 3 PBX in 3 remote offices. Routers have FXO, FXS & E&M ports connected to PBX. We are exchanging some PBX extensions with other PBX by configuring router FXO-FXS trunk. I also configured tie line by E&M ports.

My problems are:

1. Sometimes few FXS ports are not getting remote PBX dial-tone & hang. If we shut/ no shut or reboot the router then it works fine again.

2. Sometimes following message is coming from my E&M port & the call is not going by this port. ""*Nov 21 07:34:21.789: flex_dsprm_tdm_xconn: voice-port (0/0/0), dsp_channel(/0/4/5)""

But I have DSP allocated to all voice ports. Do I need more DSP ?

3. Sometimes when we put access code to call remote office by E&M ports, it can?t place the call, although the line is free. If gives a busy like tone.

4. Though my ping time is 12ms but a call by E&M port takes 3 seconds to ring. How can I reduce this delay time?

I am very much worried about this problem. Please help me to solve these problems.

New Member

Re: some VOIP problem_ pls help

gateway and IOS aside. How many voice ports do you have in your router ?

a sh voice prt summ will let you know if any problems. are they all in service?

with regard to your E&M - what type are you using? 2 or four wire ? for UK type five E&M is best, beware this is often annotated as type 1 by PBX vendors. Also, for your e&m lines, for call setup if you can afford the bandwidth change the config from tie-line to trunk with sig immediate. Difference being tie-lie has to build the cct prior to signalling which will take time but consumes no bandwidth when dormat - opposite is true of trunk. by the way what value do you have for your inter digit timer? As a way to resolve quickly down your fxs/fxo's . Setup a single e&m line as above insure your policy is appropriate and applied. make and recieve a call. If speech quality seems ok try a fax as well, moitor from CLI your policy for drops and errors if seen, then debug. hope this helps. if you can - post your sigificant run cfg output for both ends. it would help me help you. good luck.

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