Unity and Callmanager with Tadiran

[fromaj]

I have a Callmanager 3.12a system with Unity 2.46. All TSP upgrades have been done. I also have a couple of VG200s with FXO-M1 ports in them to connect to analog station ports on a Tadiran PBX. The ports are loop start. Here is the issue. The VOIP people can call out through the VG200s and the tadiran users can call in to VOIP phones. When the tadiran phones call in and the phones roll over to voicemail, the tadiran users can leave a message, then hang up, and the VG200 port hangs. We are not sure if the problem is the unity system that is not releasing the port and allowing the VG200 to reset, or if it is the VG200 not releasing. we can reset the port on Unity and the vg200 will then reset. Finally, after the port is reset, you can listen to the voicemail. When you listen to it, the message plays, but it ends with a fast busy. I have tried enabling supervised disconnect, and subsequently disabling it. I have done the same with battery reversal. We have tried several versions of the vg200 IOS. The switch integration is VOIP with Callmanager3.01 or later not a dual switch integration. I appreciate any help.<br><br>Alan Jackson<br><br>

[#2]

It's a disconnect supervision problem that is very common with loop start lines. There are a couple of things you can check into, but it sounds like you might have already checked these out.

The most important information you will need is what does the Tadiran send that analog port for a disconnect signal?

First of all, see if the Tadiran can provide an "open loop" or "loop drop" upon disconnect (the terms are synonomous). And if it can, try to use an open loop or loop drop with a duration of 750ms or more. That should trigger disconnect detection on the VG200, which will relay a message to CallManager, which will relay a message to the TSP, which will drop the port.

The second option is slightly more work, but should also do the trick. If the Tadiran cannot supply the loop drop, but can supply disconnect tones (dial-tone, reorder) the the VG200, you can enable disconnect detection on the VG200. Follow this link for configuration...

http://www.cisco.com/univercd/cc/td/doc/product/software/ios121/121newft/121t/121t3/dt_fxodt.htm

Bear in mind that for the duration of the VG200's detection of the disconnect tone, Unity will still be recording. That is to say, you might have a bit of disconnect tone recorded at the end of messages left from calls that originated on the Tadiran.

Steve Olivier
Software Engineer
Cisco Systems

[fromaj]

I will check on whether the ports can provide "open loop" and look at the duration as well. Unfortunately, the other link is very little use in the case of a VG200. The commands that are detailed are not available on that piece of hardware. I looked at that post when this all began. Is there any way to make the Unity server recognize that the call has ended and drop it? Since this is a h323 gateway, I am thinking that the Callmanager may be out of the loop.

Alan

[#4]

The VG200 does support it. I might have sent an old link. Try this one, you may need a CCO account to get there...

http://www.cisco.com/warp/public/788/signalling/fxo_disconnect.html

Here are a few snippets....

"The FXO voice interface card detects that power is no longer present and interprets this as a supervisory disconnect. This is the signaling looked for when supervisory disconnect is configured on the voice-port (default configuration). This is available on the Cisco 1750, 2600, 3600, 3810, and VG200 analog FXO ports in all versions of IOS."

"If the switch is configured to provide a supervisory tone, the router’s FXO port will interpret this as supervisory disconnect and disconnect the call to the far end.This is the signal the router is looking for when the command no supervisory disconnect is configured on the voice-port. This is available on the Cisco 1750, 2600, 3600, 3810, and VG200 in all versions of IOS."

"Battery-reversal is supported on the existing FXO ports of the Cisco 3810 and starting with Cisco IOS Software Release 12.0(7)XK (rolled into 12.1.3T), it is supported on the VIC-2FXO-M1 and VIC-2FXO-M2 for the Cisco 2600/ 3600 routers and VG200 gateway."

No, CallManager is not out of the loop. The H.323 connection from the router goes straight to CallManager. CallManager is going to proxy that GW-Unity call control connection via skinny. Unity will recognize a disconnect event as long as it is sent from CallManager. For that to happen the GW is going to have to send a H.323 disconnect to CallManager and then CallManager will relay it to Unity.

Steve Olivier
Software Engineer
Cisco Systems