Performance of Fast Routing Algorithm for Vertically Stacked Optical Banyan Networks with Link Failures and Given Crosstalk Constraint

For faster connection establishment, previously proposed Pruned vertically Stacked Optical Banyan (P-VSOB) networks used plane fixed routing (PFR) algorithm, and has O(log(2)N) routing complexity. Blocking probability has also been analyzed for these kinds of networks with given amount of crosstalk. In EP-VSOB networks, a few regular banyan planes are added with the P-VSOB networks. Necessary routing algorithm, namely, PFR_LS and PFR_RS show that this switching network can reduce the blocking probability to very low value while keeping the hardware cost almost the same as that of P-VSOB networks. Both these algorithm also have the time complexity O(log(2)A). This paper deals with the blocking behavior of EP-VSOB (Extended pruned VSOB) networks having link-failures and allows crosstalk constraint. Our simulation results show that crosstalk adds a new dimension to the performance analysis of practical EP-VSOB networks where some links are failed. The results show that if we allow some CSEs to the network then blocking probability decreases to low value for both PFR_LS and PFR_RS algorithm. The results also show Chat the blocking probability of the EP-VSOB networks does not always increase with the increase of link-failures; blocking probability decreases for certain range of link-failures, and then increases again.