does OCS Server select the Exchange UM Server for
Step 1: UserA makes call to the number assigned
Step2: Call reaches OCS Front End server
Step3: OCS Front End Server does Reverse Name
Lookup and Find out SIP URI of UserB
Step4: OCS Front End server finds the active end
point of UserB
Step5: OCS Front End Server forks the call to all
active end points where UserB has logged in.
Step6: UserB doesn't pick up the call
Step7: OCS Front End server finds out if UserB is
enabled for Unified Messaging.
Step7: OCS Server will determine dial plan of the
user and query Dial Plan to know the list of UM Servers
Step8: It will select the UM Server based on
routing logic and OCS Server will forward the call to
Note: If first UM Server is not available then
OCS will select the other UM Server attached to the same
Step 9: Now Session is established with UM Server
Step 10: UM Server will exchange Media packets
with UserA directly.