3527 PRI GW + GK + CUCM

Unanswered Question
Sep 21st, 2007

Issue is the following:

Inbound video from a remote H.320 Tandberg platform fails when it calls to a SCCP 7985.

Call Flow:

H.320 Tanberg places a call to a number that lives on a 7985. This call hits a video PRI terminated on a 3527 H.320/H.323 gateway. 3527 does a lookup for destination and the default path is a trunk that is between the GK and a CUCM5.1 platform to which the 7985 is registered. CUCM sees the call ingress and places it to the 7985 where the call rings.


TCS is not negotiating. If the call is just an audio call from my cell phone, the call works fine. However, when the call is placed as a video call, the call initially connects at 64k and tries to negotiate up to video, but fails and dies after 10 seconds (timeout because it would seem the remote end Tandberg is not sending its TCS).

We have ruled out the remote end by placing inbound calls from other remote video conferencing stations and have had the same issue, so, from our perspective, the issue lay somewhere between the 3527 and the Callmanager in negotiating the TCS.

Important Note:

Callmanger trunk with GK is a GK controller H.225 trunk with "Wait for Far End H.245 Terminal Capability Set" unchecked (as per SRND). Tested it out with the toggle checked and still failed.

GK configuration is as follows:


voice service voip


no call service stop


zone local TEMP mydomain.com

gw-type-prefix 1#* default-technology

no use-proxy TEMP default inbound-to terminal

no use-proxy TEMP default outbound-from terminal

no shutdown


Any help would be most appreciated. My guess is that a an H.245 pass-through configuration may be needed on the GK, but that is a grasp at straws.

I have this problem too.
0 votes
  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 0 (0 ratings)
b.hsu Thu, 09/27/2007 - 13:57

There is a bug CSCee16667 filed for this. Later releases seems to fix it.You can also try to reset tandberg.


This Discussion