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Difference between SRST and MGCP Fallback?

What is the difference between SRST and MGCP Fallback?


Re: Difference between SRST and MGCP Fallback?

srst = Survivable Remote Telephony, when the IP Phone looses connectivity with cm, the phone registers with the default gateway.

mgcp fallback = defines the fail over server in the call manager cluster

when mgcp looses communication with call manager server, the srst router will enable the ccm application and start to register the phones.

New Member

Re: Difference between SRST and MGCP Fallback?

So what is the purpose of mgcp fallback on a router, when each phone can have a list of 3 CallManagers that they can turn to?

New Member

Re: Difference between SRST and MGCP Fallback?

just like the phones mgcp gateways must register with a callmanager if for some reason the mgcp gateway loses its connection with the callmanager the mgcp fallback is another callmanager that the gateway can register with this has nothing to do with the phones it is only gateway registration. if you have a 2 callmanager cluster and all of you phones and your gateways are registered with callmanager1 and callmanager1 crashes the phones will reregister with callmanager2 and the gateway will loook at its mgcp fallback address to find callmanager2 and also register with it


Re: Difference between SRST and MGCP Fallback?

Slight points of clarification.

SRST as above mentioned is for phones to register with the router when WAN connectivity is lost to the call manager.

MGCP FALLBACK, could mean two things and i think the above posts tackle one aspect. ccm-manager redundant host addresses the fact that the mgcp gateway willre gister with a secondary call manager in an event that the first one is unreachable. ccm-manager fallback mgcp actually takes the gateway out of mgcp mode and puts it in h323 mode, when the ccm is unreachable, so the gateway can come out of the master slave envireonment and process calls, as an h323 gateway, either out to PSTN or VOIP to another gateway.

Hope this clarifies it somewhat.

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