Integrating Tandberg E20 with CUCM

[subamm0t.cisco]

Hi Everybody,

I am integrating Tandberg E20 phone as a sip endpoint in CUCM 7.0 and it regesters with no problem. However, the problem comes when you try to make an out going call to other IP phones in the cluster. it takes about 15 secs for the call to reach the other phone. During these 15 seconds I am recieving a ring back on the E20 even though there is no rining actually happening until after the 15th seconds. the E20 recieves calls with no problems.

If any one has any insight about this issue, it is appreciated.

Regards

[Jose Mendez]

Alí,

Quick thought here. Could it be that your device/line is hitting an overlapping pattern? 15 Delay seconds sounds like the T.302 timer's default value. Why don't you check if there are multiple possible patterns with variable size? Your best friend in this case is the Dialed Number Analyzer (Serviceability > Tools), search if there are alternate patterns.

[subamm0t.cisco]

Jose,

I already did that but it only matches one pattern. I thought about T.302 Timer and I changed it but it didn't change anything. It is not exactly 15 secs I did not time it but it takes about 5 ringbacks on the E20 then the other phone actually rings. The weird part is that when the other phone rings and you disconnect the call from the E20 it keeps on ringing for three or four more rings !!

[Tao Ren]

Change "SIP Min-SE Value" from 1800 to 500 on CUCM servers.

[Jose Mendez]

Alí,

Just thought of something else... Are you hitting the Dial button on the Tandberg phone? (Or anything similar)

If yes, then you are looking for the device that is not responding on time.  Is this is a SIP to SCCP type of call?Or are you dialing Tandberg to  Tandberg?

After clarifying point above,  register the  two nodes to the same CallManager node, SSH into that server, and  collect a packet capture while you reproduce the problem:

utils network capture eth0 file tandberg count 100000000 size all

1. Make sure the enpoints time is synced with CallManager's
2. Write down the exact second you start the test
   
3. Call from Tandberg to a SCCP IP Phone
4. Let the SCCP phone ring for a few seconds then pick up the call
5. End the call from the Tandberg endpoint
6. Press Ctrl+C to end the packet capture and collect through RTMT:  http://supportforums.cisco.com/docs/DOC-11588 (look for CLI packet  captures option)

A CCM Trace file woud be helpful too. Basically you want to trace the signaling on each leg and determine where the delay is. We can expect it either after you hit the Dial button on the E20 and before CallManager receives the INVITE message, or after CallManager gets the signal and before it sends it out to the SCCP phone. That is why we need your hand watch to be in sync.

If you want you can upload the trace file and packet capture, along the MAC and IP Addresses (phones and server), calling/called numbers and exact time you started the test.