Transcoder location question

[sps210001]

We are currently using a product called CallRex to record calls. CallRex does not support ILBC (which we are using across our WAN Connection)

My initial thought is to configure a couple of 28xx/29xx routers with enough DSP resources to transcode the calls from ILBC to G.729 so the call can be recorded.

Configuring the transcoder via IOS CLI

Adding the new transcoder (Media Resources>Transcoder)

Name: XCode-LocationA

Device Pool: LocationA

Name: XCode-LocationB

Device Pool: LocationB

Etc.

My question is how do I force the phones at each location to use the Transcoder to convert ILBC to G.729 so the CallRex server (which is located in the same physical location as the phone) can record the call?

[Dennis Mink]

Well you would need to put your Call Rex server in its own device pool, with its own region.

you will need to create the region relationship the phones are in with the Call Rex server to use G729.

Depending on what phones you are using (there is a good chance that they simply support G729) you might not need Xcoding.  if you do, then the first Xcode resource in your phone;s Media resource group will be chosen. 

[shelfdrilling.it]

Hi,

Let's start with fact that you need universal transcoder instead of standard transcoder. This is becuase none of the call legs is g711. You are xcoding from g729 to ilbc. 

Can you use span to forward the rtp stream to callrex server? 

[sps210001]

Thanks for the responses.



I took a look at the universal transcoder and that does make sense.



Our CUCM cluster is at our HQ location. There are 5 locations (one of which is at HQ). Each site has its own CallRex Server. We have some old hardware laying around (after we converted 28xx/29xx to 43xx series routers for iWAN purposes) I am thinking that I need to configure a router with some DSP's for each separate location so when the RTP stream comes across the wan (In ILBC) the phone will then invoke the local transcoder at the site to convert from ILBC to g729.



I am not real savvy yet with the way transcoders work, when they are invoked etc.



CUCM is set up with regions (all set to prefer ILBC) We have a region for each physical location.

Attached is the port mirroring guide for CallRex



As far as CallRex goes, yes we are spanning to forward the RTP stream. The software just doesn't support ILBC. Hence why local calls on the same physical section of the network where a CallRex server is can record fine, but as soon as you dial an extension across the WAN, it will work fine.



We are in the middle of converting our locations to SIP and getting rid of our old gateways.

[Manish Gogna]

Hi,

Please check the last response of Karthik Sivaram in the following post

https://supportforums.cisco.com/t5/other-collaboration-voice-and/transcoding-between-ilbc-and-g729/td-p/1597152

Manish