SRST is fallback for when the main call manager is not available for the phones, and provides real basic phone functions during the time that call manager is not available.
CME doesn't need call manager and is more feature rich then SRST but doesn't have all the features of full blown call manager neither, and has some of it's own differences. Phones can't fallback to CME if call manager fails.
It depends on what features the users need at the site, if you go with CME then the site and phones don't use the call manager. You can route calls between the CME site and Central call manager by using voip dial-peers and defining a gateway and route-patterns on the call manager to route calls to the CME site.
If you want to start deploying phone systems at each of your branch and your HQ has not yet moved to IP Telephony (using Callmanager) you can start using CME at each branch. Voice mails are stored locally on the HDD of CUE module local to each branch and each system is administered locally. Once the HQ moves to IPT, you can convert the configs on each CME router to SRST and make all the phones in each branch local to the Callmanager at HQ. YOu can still run a combination of CME and SRST. Just that each CME system will be running on its own and sending calls to other branches using H323 trunk to the Callmanager.
I was looking at deploying 1800 series routers on these sites but they dont support CME, however they do support SRST, if I go for the 2800 series there would be a big price jump for these many sites. Thats why I was thinking if I could use SRST.
I'm not able to access my old voice mail messages all of a sudden. The recording says something like 'the message is currently not available'. This has never happened before in all the years I have been using this system. I have t...
If you have 2 ISR routers, one acting as Failover, do we need to have both the same number of SRST licenses on the 2 routers?
No. You will only need the SRST licenses on the primary router. Because this feature...