An Exchange UM dial-plan supports three different security levels: Unsecured, SIP Secured, and Secured. The following table shows the differences in terms of Mutual TLS and SRTP for the various security levels.
VoIP Security |
Mutual TLS |
SRTP |
Unsecured | Disabled | Disabled |
SIP Secured | Enabled (required) | Disabled |
Secured | Enabled (required) | Enabled (required) |
If you plan to integrate Exchange UM with Office Communications Server 2007, which one should you choose?
Unsecured is not an option, since Mutual TLS is required between Exchange UM and OCS. You can either choose "SIP Secured" or "Secured", unless your deployment includes Communicator Phone Edition (aka Tanjay). In this case, you should configure "Secured".