An especial type of multistage optical network(i.e.the asymmetrical multistage omega network) has been proposed for solving the problem of complicated topological structure,high hardware cost of crossbar network,and the complexity of optical implementation of the rearrangeable nonblocking multistage network,such as banyan+banyan-1 and omega-1+omega network.Its topological structure has been discussed and analyzed in detail,and the corresponding routing algorithm has also been proposed and improved to fulfil...