SRST with T1 CAS MGCP Gateway

[elbyte]

Hello - we are trying to configure SRST on our T1 CAS MGCP gateway. We have been informed by a Cisco engineer that we cannot use SRST on a T1 CAS MGCP gateway and that the gateway must first be reconfigured as an H.323 gateway in order to implement SRST. Router is version 12.2(15)T14 and CCM 4.1 Any comments would be truly appreciated...thank you.

[fred.s.mollenkopf]

SRST doesn't support MGCP but does support MGCP to H.323 failback. You can still configure your router/CCM with MGCP then use the fallback commands for MGCP.

Looking at the SRST 4.0 system guide, page 42, T1 CAS is supported. With your version of IOS you would be running SRST 2.1, this is also supported.

http://www.cisco.com/univercd/cc/td/doc/product/software/ios122/122newft/122t/122t15/srst21/srstv21.pdf

http://www.cisco.com/univercd/cc/td/doc/product/voice/srst/srst40/srst40ad/s40sa.pdf

The ccm-manager fallback-mgcp command was added in IOS 12.2(11)T so it should be in your version. This is what you would need to do MGCP fallback to your H323 along with the call application alternate default.

http://www.cisco.com/univercd/cc/td/doc/product/software/ios123/123tcr/123tvr/vrht_c4.htm#wp1061367

http://www.cisco.com/univercd/cc/td/doc/product/software/ios123/123tcr/123tvr/vrht_c1.htm#wp1670149

I would say it might be possible as I don't see anything saying no. Though remember MGCP fallback to H323 over SRST doesn't have call preservation.

Lastly here is a document on the SRST MGCP/H323 fallback.

http://www.cisco.com/en/US/tech/tk1077/technologies_configuration_example09186a008012ecc6.shtml

Please rate any helpful posts

Thanks

Fred