Support for RFC 2543-compliant branch parameters
RFC 3261 is the most recent SIP RFC, it obsoletes RFC 2543. However, some SIP implementations may use RFC 2543-compliant SIP calls.
rfc2543-branch VoIP profile option allows the FortiGate to support SIP calls that include an RFC 2543‑compliant branch parameter in the SIP Via header. This option also allows FortiGates to support SIP calls that include Via headers that are missing the branch parameter.
config voip profile
set rfc2543-branch enable