You must configure the Topology Hiding feature of Avaya SBC when setting up a connection to the Microsoft Teams system. Topology Hiding masks the IP address of the Avaya SBC system used with Microsoft Teams, but exposes an FQDN that the Microsoft Teams SIP proxy can use for connectivity.
For example, you might set up the options as follows:
Header = From
Criteria = IP/Domain
Replace Action = Overwrite
Overwrite Value = the FQDN of the Avaya SBC system
For more details about Topology Hiding, see Administering Avaya Session Border Controller.
