How does OCS select Exchange UM Server...

When any external or Internal user calls a user in OCS-UM enabled environement, The OCS Server selects the UM server for Voice mail facility. Following steps explain how does this happen -

  • OCS will determine SIP Address of the dialed number
  • It will check if the user is enabled for Unified Messaging. The attribute it will query is "MSExchUMEnabledFlag"
  • If the user is enabled for UM, It will query proxyAddress (EUM type) of the user.
  • OCS Server will find out the dial plan name from EUM Proxy Address
  • OCS Server will query Dial Plan object to find out the list of Exchange UM servers assigned to it.
  • OCS Server will select the Exchange UM Server based on routing logic
  • If it doesn't get response from the first Exchange UM Server it selected, It will select the second Exchange UM Server

Routing to UM server involves determining which UM server is able to service the request of the user and how to route the call to that particular UM server

The routing feature has following characteristics:

  • Determine the UM server to route the call.
  • If more than one UM server is linked to the dial plan then try a different server if the first server does not respond.
  • Generate request that UM can understand and process.
  • Establish media session between UM server and UC client.

Comments

  • Anonymous
    January 01, 2003
    No.. you just need to install and configure UM, and assign this UM server to the right dial plan. you don't need to re-run the exchange script.

  • Anonymous
    January 01, 2003
    So question on this in regards to adding a new UM Server.  If we already have OCS and UM integrated, I'm assuming this will just consist of adding the new UM server to the dial plan?  Would we have to re-run the Exchange Script to re-configure objects to take the new UM server into consideration?

  • Anonymous
    January 01, 2003
    Sweet one.. I Was looking for this at many places.. thanks!

  • Anonymous
    June 10, 2010
    Do you know what routing logic the OCS Server actually uses to determine which Exchange UM Server to select?

  • Anonymous
    November 30, 2010
    Do you know what routing logic the OCS Server actually uses to determine which Exchange UM Server to select? Is it based on the called user's location or the ocs server's location?