receiving end of up to a total of 96 electrical data signals from the processing cards 130 and a further 112 electrical data signals from other chassis via the optical ports a b c d for a total of 208 received electrical signals similarly by virtue of its output electrical interfaces out 0 out 207 the switch fabric 200 can transmit up to a total of 96 electrical data signals to the processing cards 130 and a further 112 electrical data paths to other chassis via the optical ports a b c d for a total of 208 transmitted electrical signals in order to accommodate the switching requirement of the switch fabric 200 the latter may be implemented as a single non blocking cross point switch matrix of the requisite size 208 u00d7 208 this would allow any of the electrical paths p 0 p 95 to be connected to any of the optical paths a 0 a 31 b 0 b 23 c 0 c 23 and d 0 d 31 however it is noted that not all of the electrical signals received from the opto electronic receivers 210 will need to be relayed to the processing cards 130 rather some of these may need to be immediately re routed back to the optical ports via the electro optical transmitters 220 similarly some of the electrical signals received from the processing cards 130 will need to be immediately re routed back to the processing cards 130 although possibly to.