Showing results for 
Search instead for 
Did you mean: 
Walkthrough Wednesdays

Can a voip transcode chan be created on 2811 gateway without signalling?

Is there a way to nail up an IP to IP transcode channel through a 2811 without any SIP (or other) signalling using IOS? I'd like to stream IP media through the gateway using test equipment that cannot perform the SIP signalling. The alternative is to hook up a few endpoints, start a sip session to open up the media ports. unplug the endpoints and turn on the test equip to stream the media. However, I'm not sure there is any keep alive that might kill the session after some interval of inactivity.

Steven Holl
Cisco Employee

You need signaling with a codec mismatch to go through the device where the transcoder is registered for it to be invoked.

Your best bet is to nail up a call, and then make your test device transmit media on the same port/ip that the call has been setup from, and unplug the original endpoints.

If the test equipment runs on *nix, could you use sipp to do the call signaling?


Thanks very much for your response. I've coded up a very simple SIP server (INVITE, OK, ACK, BYE) and added it to the test equip. that is sending media data to the gateway. Since this is part of lab test, everything about the call is controlled.

I'm assuming that the 2811 can be set up as UA without requiring registration to a proxy. I notice via IOS commands there is a way to give the 2811 UA a server address, so I'm hoping that is all that is needed beyond normal IOS setup for SIP dial-peer.

DUTa --> INVITE --> GW --> INVITE --> DUTb

DUTa  <-- OK <-- GW <-- OK <-- DUTb

DUTa --> ACK --> GW --> ACK --> DUTb

DUTa <--> media <-->  GW <--> media <--> DUTb

GW = 2811

DUT = is a Device Under Test

I added a simple SIP UA client/server stack to DUT. I'll tell the gateway that the DUT is the server. And do not plan to have the GW register with proxy.

Seems doable, right?

Content for Community-Ad

Spotlight Awards 2021