A Parallel Self-Routing Rearrangeable Nonblocking Multi- $\log _{2}N$ Photonic Switching Network

A new rearrangeable nonblocking photonic multi-log ₂ N network DM(N) is introduced. It is shown that DM(N) network possesses many good properties simultaneously. These good properties include all those of existing rearrangeable nonblocking photonic multi-log ₂ N networks and new ones such as O(logN)-time fast parallel self-routing, nonblocking multiple-multicast, and cost-effective crosstalk-free wavelength dilation, which existing rearrangeable nonblocking multi-log ₂ N networks do not have. The advantages of DM(N) over existing multi-log ₂ N networks, especially Log ₂ (N, 0, 2^{??log2 N/2??}), are achieved by employing a two-level load balancing scheme-a combination of static load balancing and dynamic load balancing. DM(N) and Log ₂ (N, 0, 2^{??log2 N/2??}) are about the same in structure. The additional cost is for the intraplane routing preprocessing circuits. Considering the extended capabilities of DM(N) and current mature and cheap electronic technology, this extra cost is well justified.