Unanswered Question
May 3rd, 2007

I am interested to know when one would choose SRST over CME or vice versa.

What advantages does one have over the other ?

Some threads I have read suggested deploying cm and unity at the main site, with SRST deployed in remote offices, some talk of deploying cme at remote offices instead of SRST.

Would appreciate any links or comments

Thanks in advance

I have this problem too.
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Overall Rating: 5 (2 ratings)
thisisshanky Thu, 05/03/2007 - 06:27


When you have a centralized CM deployment, your remote sites may be deployed with either SRST or CME. The choice of which one to use depends on how much bandwidth you have available in the wan to support the signalling traffic for the X number of phones you have out in the remote sites. With CME, signalling traffic remains local to the lan at each remote site and each remote will have to be managed on its own. In both scenarios, interoffice calls do consume bandwidth across the wan.

Off late most of my centralized deployments with remote sites are deployed in a hybrid mode. Its called CME with SRST fallback support. Its pretty cool, because you can have all CME like features at the remote site, when wan fails and phones failover to the router at the remote site. You can setup BACD, hunt groups, pickup, call park etc.. This is not available with traditional SRST. Check this link for more details.



PS: please remember to rate posts!

mark_gardner Thu, 05/03/2007 - 06:37

I'll give you a 5 for that ;)

You wouldnt have any links relating to recommendations on bandwidth when deploying centralised cm solutions ?

Thanks for previous post

Helpful as always

thisisshanky Thu, 05/03/2007 - 09:19


Thank you for the rating. For CME deployments use the following SRND

For CM deployments, check the following SRND.

The recommended bandwidths are in this link.




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