Lucent Technologies Octel Unified Messenger Concepts and Planning Guide 101-1620-005 - Manual (Page 35)

Sizing the system
101-1620-005 2-9
Calculating the number of voice servers required
Having established the total number of voice ports, it is possible to
calculate the minimum number of voice servers needed. The minimum
number of servers is equal to the total number of ports needed, divided by
the number of ports to be installed on each of the servers. An Octel
Unified Messenger voice server can support up to 24 voice ports.
To determine the correct (not the minimum) number of servers needed, it
is necessary to consider the effects of the following factors:
n The voice mail domain design. For more information, see
“Design rules for voice mail domains” on page 2-3.
n The PBX configuration and integration.
n Potential heavy processing demands, such as those imposed by
the tracing system.
Note: The Octel Unified Messenger tracing system should
be installed on a separate machine that does not run
the voice server software. This is particularly
recommended for any implementation of Octel
Unified Messenger that uses eight or more voice
ports.