could you please detail bit more about the issue?

Is it the outgoing calls that fail? / transferred calls?/ or inbound calls?

is it only for those ip phone which are connected through VPN? 

does calls made from ip phone with in the network (without VPN) also experiencing the same issue?

if it is only the VPN phones, then please also check your firewall configuration, if it blocks anything 

Shalid,

Customer informed me it is in both directions and not happening every call.  One CCIE from our company believes it is a SIP timer expiring as it always drops at the 15 mins mark.

Only 1 person is experiencing this. No one else has reported this.

What and where can I see the SIP timers involved?

Thanks!

JC

John,

I'm not a firewall guy, but if this is happening consistently at 15 minutes, this sounds to me like a session timeout on the firewall(s)

Glenn

Thanks Glenn.

It's not consistent. 90% of his calls are fine all day. I was late in grabbing the traces so I'm looking for an excuse to have him report when it happens again.

Is there something I can do to let him know a change was made and have him report if/when it happens again? 

John,

Can you tell from the CDR records which side is terminating the call?

Glenn

When at look at these calls in CAR, I see both the origcallterminationonbehalfof and the destcallterminationonbehalfof codes are 13

John,

I don't remember what the resolution was in my case above since it was many years ago but I'm pretty sure it was firewall related.   Do you have access to the logs of the user's firewall and/or any other firewalls that may be in the mix?   I would also try to rule out any network problems.

The best I could ever find for code 13 was:

The call is terminated by Call Control because some error it received or some timer expired, then the onBehalfOf value is set at 13 (Call Control).

Glenn

Responses from customer:

Home or Office user?    Home User

What is the Model of his Phone he uses?   7965

Is anyone else sitting near Scott having this problem?    No he works from home

Before this problem began, how long was the phone he is using now working properly?  for months, he started having problems out a week ago.

Was there any changes you are aware of that may be contributing to this?     No changes to his configuration that I know about.

Update 6 months later.  Sorry I should have updated earlier.  To fix my issue I registered the phone in question to a different Call Manager. I used the same CUCM other people were registered to who didn't have any issues with drops. Hope this helps.

More info from client...

• were all incoming calls

• I thought it was every time because it happened 3 times in a row but then it did not happen on an incoming call yesterday.

• Never noticed it on internal calls.

PSTN - SIP TRUNK - CUCM - NETSCREEN NS50 - INTERNET - NETSCREEN 5GT - VPN PHONE