UAC does not Support Session Timers

If the UAC’s initial request does not include a Session-Expires: header, then the 200 OK will include the session-timer-profile, session-expires value on the ingress leg in the Session-Expires: header.

The Oracle® Enterprise Session Border Controller also inserts the refresher parameter as configured. The orientation of UAC/UAS on the Oracle® Enterprise Session Border Controller’s view of a call leg can change if later in the call flow the endpoint designates the Oracle® Enterprise Session Border Controller as the refresher.

Note:

When the request doesn't support Session Timers, the Oracle® Enterprise Session Border Controller’s reply adds session timer support according to configuration.

If the Oracle® Enterprise Session Border Controller receives a message with a Require: timer header, and the inbound SIP interface or the final UAS do not support session timers, a 420 (Bed Extension) is returned to the UAC.