An enclosure services processor card is arranged to selectively split a fiber-channel
arbitrated-loop (FC-AL) into two split loops. The card is adapted to plug into
a backplane for a rack enclosure and includes a first switch operatively connected
to a hub for the FC-AL. The hub comprises a plurality of port bypass circuits,
each port bypass circuit being connected to a pair of tracks which in use connect
to a respective one of each of the devices comprising the fiber channel arbitrated
loop. The hub further comprises a pair of switches operatively controlled by the
first switch, the pair of switches being disposed between respective port bypass
circuits at which the loop is to be split. In a first state the pair of switches
connect the devices in a single loop and in a second state the pair of switches
divide the devices into two split loops.