The SBC includes an IPSP configurable flag to prevent relaying an end-to-end session refresh UPDATE/re-INVITE locally (when the "End To End Update" and/or the "End To End re-INVITE" flags are enabled) using the IPSP flag “Suppress E2ESession Refresh”.
When “Suppress E2ESession Refresh” is enabled, the SBC processes the session refresh UPDATE & re-INVITE locally without relaying it. The default value is "Disabled".
Note that an UPDATE request without an SDP and an UPDATE request with the same SDP are considered session refresh updates. These updates can exist in an early dialog established state or a call established state. Also, a re-INVITE with the same SDP is considered as a session refresh re-INVITE.
Configuration details: