The firewall IPD does not affect the DeltaV system's limit of twelve switch hops in series. For example, ten switches can be on one side of the firewall IPD for workstations (and controllers that do not need protection and do not have assigned CIOCs on the protected side), and two switches on the protected side for controllers and their assigned CIOCs only, or six switches on one side of the firewall IPD and six switches on the other side, and other combinations for a total of 12 in series (daisy-chain).