Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 
New Member

ip softphone problem

My config is as follows:

CCM 3.1

AS 5300 gateway with 60 channel VOX (2 x Q931)

IP softphone 1-2-2

I can make internal calls but I can't make calls to the pstn (ie through the gateway). I hear the pstn phone ring once and the call terminates automatically. Also, I cannot make calls to the softphone from the pstn.

Any ideas?

Cisco Employee

Re: ip softphone problem

What codec are you using? Are you using g.711 or g.729? Are you sure the as5300 can ping the softphone pc. What happens when you try to call the softphone from the pstn. Have you looked at a detail ccm trace for an inbound or outbound call? What does debug isdn q931 show on the 5300? Specifically who is disconnecting the call the pstn or 5300/CCM?

Thank you,


New Member

Re: ip softphone problem

You're right- the problem seems to be the codec. I have a test Call Manager running ccm 3.1 and when I used this in the configuration it worked fine. The only difference was that the relevant codec was 'wideband' (between the regions). It didn't work (excternal calls) when I changed the codec to g711, g729, g723.

CCM 3.0 doesn't have a wideband setting and external calls still aren't working. DOes CCM3.0 support softphone?

New Member

Re: ip softphone problem


I have exactly the same problem as you, except I cannot solve it with the same solution.

I'm using SoftPhone, IP phones, and also Netmeeting H323 clients.

All my infrastructure is working fine when we place calls internally, and it's working fine when we place calls to external world from IP phones AND from Netmeeting workstations that are registered on the CCM!

Only with softphone, when I call outside, it rings one time only, and then hang up.

I really don't understand what is the difference between an IP phone or a Neetmeeting, which are registered on the CCM in the same region, and a SoftPhone which share also the same definition!

I'm pretty sure also there is a CODEC problem, but contrary to Netmeeting, with SoftPhone we cannot manage easily the CODEC definition on the workstation.

And changing on the CCM, does not changes anything.

So, what did you change exactly on the CCM, and do you have any idea of this other problem ?


New Member

Re: ip softphone problem

To get external calls working:

(1) make sure your relevant voip dial peers on the gateway are set to use g711ulaw and not g711alaw.

(2) Softphones should use the wideband codec for external calls. You'll need to upgrade to CCM3.1x and set up the devce pools and regions if you haven't already...

(3) Softphone to IP phones should be unaltered in terms of codec.

Let me know how you get on...


CreatePlease to create content