Nortel CS1000 Cisco H.323 Integration

[ciscochris]

We have a Cisco CallManager 8.0 H.323 integration with a Nortel CS1000 system. We have everything working except transfers. The Cisco can transfer to a Nortel phone. The Nortel phone can transfer to the Cisco and the call will connect but we will not get audio. However, if we use the conference feature and then drop off the call, it works successfully. Is this an integration limitation or is there configuration missing?

Thanks
~Chris

 

[macaodha]

Perhaps you need an MTP? You can find this and other hints in the SRND for CUCM 8:

Media termination points (MTPs) are generally not required for normal operation of the H.323 trunk.
They are, however, required for communication with devices that are H.323 Version 1, that do not support the Empty Capabilities Set (ECS) for supplementary services, or that require H323 FastStart.
To test whether or not an MTP is required, use the following simple procedure:
1. Place a call from a phone via the H.323 trunk to the other device. This call should work normally.
2. Place the call on hold, then resume it. If the call drops, then it is highly likely that an MTP is required
to ensure interoperability between Unified CM and the other device.

 

[nortelneo]

Hi chris/macaodha,
We have CUCM 6.1.2 connected to a CS 1000E using H323. Calls from a cisco phone to the nortel system cannot be transferred, while calls from nortel to the cisco system can be transferred at the cisco side. we are using g711 a law on both sides.
Can you tell me how I can fix this?

 

[ciscochris]

Hi nortelneo,

Macodha is correct that you will need MTP resources and having the MTP required box checked on your gateway.

We have eliminated our scenario down to having issues when there is a Nortel IP phone in the mix. All transfering and conferencing scenarios work between Cisco phones and Nortel digital sets.

Is there an equivalent of MTPs on the Nortel side that we need?

 

[nortelneo]

Hi,
Yes, the MTP option is checked on the CUCM and I tested the hold scenario, and the call turns one way when i release the hold, the cisco side can hear me but i cant hear them. I am not aware of any thing similar to MTP at the nortel side.
Would appreciate any more info.

Thanks.

 

[plmartin314]

I have the same issue with CUCM 8.5 and Nortel CS1000E 5.5. MTP on the cisco side does not solve the issue. connect a call between the cucm and nortel, place it on hold on the Nortel phone and when you come off of hold there is one way audio - nortel to cisco is good but no joy on cisco to nortel. put it on hold on the cisco side and audio is fine when you come off of hold.

A year ago did some testing with a cisco ios router acting as an h323 gateway and registered to Nortel NRS and had very similar issue.

config is having cucm 8.5 register as an H.323 RAS endpoint to Nortel NRS, linux version 5.5.

On the other hand have been more cuccessful with SIP integration with all the same pieces, at least have not come across the one way audio issue - or at least solved audio issues by using MTP.