mgcp and srst

[rich.wright]

I'm having trouble finding a document that describes how to set up an mgcp gateway to use srst. I know I need 12.2.(11)t. What I don't know is which h323 commands I still need to keep it working during srst. Do the mgcp commands override the h323 commands during normal operation?

[mschlenger]

With MGCP, your gateway is going to be a dumb endpoint. Call Manager will have total control over calls placed in and out of this device . SRST only works with H.323 at this point ,because in the event of an outage, that MGCP gateway will not be able to contact CM for call control and it does not retain any configuration parameters locally on that device. If you look for SRST on CCO, you'll find commands like dial-peers and the such that will hold the call control intelligence locally in that device in the event of an outage. Your IP phones will register with your voice enabled router and that device will make and receive phone calls based on your dial-peer configuration.

"Normal operation" will be defined in how you configure the gateway within Call Manager. If you set it up the ports as MGCP, then that will be your primary siganlling protocol. If you add it as an H.323 gateway, then that will be the primary signalling protocol.

Note: Last I heard, SRST only supported H.323 signalling, so I'd double check with TAC in that your configuration is supported.

[tringwelski_2]

Yes, mgcp does support srst, there is a command on under the call manager fallback: "trunck access code 9 pri" etc. when you add this command, the dialpeers are autocreated for h323 fall back for inbound/outbound dialing, you may need to add some translations for inbound # which are not did's ( defined extensions in that office). So you will not need any manually greated dialpeers to work, you should do plenty of testing to understand how this will work in your enviroment.

Todd