VTA, CCM 4.1.3, and Bandwidth

Unanswered Question
Aug 26th, 2008

Looking for an explanation as to why one method works over another.

Environment:

VTA 2.x client (near the latest)

CCM 4.1.3sr1

MPLS, with 256k voice, >=384k video

Two locations, each with own cluster

Locations on each cluster set to same bandwidth.

Codecs same.

Using ICT (non-GK)

Scenario 1:

One phone on each cluster place video call to each other. Works for a day or so. Call finally fails due to lack of bandwidth. Resync's and changes to bandwidth, including unlimited, prove futile.

Scenario 2:

After video call and changes fail....

Take phone from one location\cluster, and register it to the other location\cluster. Bandwidth therefore is "unlimited".

Video call works flawlessly, and will continue to work flawlessly.

This is not a bandwidth issue. Same pipe, same routes, same equipment, etc.

In the past, many issues we've had with this could be attributed to our firewall configs.

But I'm not convinced anymore. Something seems wrong with CCM's bandwidth calc logic.

Supposedly TAC emulated our setup in lab environ with 4.1.3sr7 (engineering only ??) and got similar results, but we never got a resolution.

Anyone have some insight on this ?

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Anonymous (not verified) Mon, 09/01/2008 - 17:53

Cisco CallManager checks for the available bandwidth for each device before making a call. If no bandwidth is available, Cisco CallManager will not set up the call.

http://www.cisco.com/en/US/docs/voice_ip_comm/cucm/trouble/4_1_3/tb413ch6.html#wp1040724

Call Admission Control

http://www.cisco.com/en/US/docs/voice_ip_comm/cucm/srnd/4x/42cac.html

The calling party and gateway are in different regions, between which the Video Call Bandwidth is set to None.

mlebus Tue, 09/02/2008 - 08:34

Thanks for the reply. I have reviewed these doc's before, but will take another look at CAC doc.

The primary issue is that one of the two call managers involved will have a "VideoOutOfResources" value, as displayed through the RTM --> Locations.

As an example, had two successful video calls on Friday. No one was here Sat, Sun, or Mon...and that same video call failed this morning.

The problem was one call manager reported a "VideoOutOfResources" for the called party location. No one else had made a video call to this location between my last call Friday and my first call this morning.

Any thoughts on what causes this, fixes for it, etc ?

What is the logic behind "VideoOutOfResources" ??

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