This configures an alternate TCP port, other than the FCIP Well-Known port, on which this FCIP entity listens for new incoming TCP connection requests, with a value of zero meaning it only listens on the standard well-known port. Configuring a non-default port here is a specific, deliberate choice usually made to route FCIP traffic through firewalls or NAT devices that have a custom port opened, or to run multiple independent FCIP entities distinguished only by port. A SAN extension link traversing a firewall that only permits a custom-opened port like 3260 would need this object set to 3260 to accept incoming connections through that firewall rule.