 know that the blocking probability for random connection requests is (N,W)=WPg(N)[1-Pg(N)W-1 (10.5) where, (p) is the probability that in the observation time a request arrives on the considered wavelength and is directed toward the considered output; it is (10.6) Telecommunication Networks 10.3.2.2 PWC Transparent OXC: Example of Performances Let us assume the same switch fabric already considered for the PWP and WCs based on SOAs in a MZI configuration. We have to remember that such WCs, in principle, cannot be traversed by the signal without changing wavelengths. Thus, we will assume to adopt at the input the configuration of Figure 10.22, where the 2 x 2 switch is used to bypass the WC if the signal is not to change wavelength. If this solution is used, the OXC becomes nonblocking as far as the inner blocking prob- ability is concerned. Naturally, a connection request has still to be rejected if the target output link is already saturated, but no switch architecture can send more signals into a saturated transmission system. To elaborate a power budget, we need to decide the switch fabric architecture. Let us assume realizing our WN X WN (450 X 450 in our case) with a strictly nonblocking Clos switch. If we use MEMs 3D switches, we can select the three characteristic numbers of a Clos switch as n = 10, r = 45, m = 56. The condition m 2 n + 1 is fulfilled and the switch fabric is nonblocking. We need to construct the switch fabric out of 56 matrixes 45 X 45 and 20 matrixes 10 X 56. Let us assume that the power consumption of these matrixes depends on the greater between the number of input ports and the number of output ports (compare the 3D architecture). Thus we can say, by comparing with Table 5.8, that a single 10 X 56 matrix has a power consumption of 700 mW, while a 45 X 45 matrix burns approximately 600 mW. Also adding here 500mW of drivers, control electronics, and SO on, the overall power consumption of the equipment is approximately 48W. Considering for every component of the switch fabric, a loss o