Study On Fast Dynamic Optical Link Establishment In Wavelength Router Optical Network

In this thesis, based on deep theoretical and pratical research work on the Router Wavelength Assignment (RWA), the calling and connectiong proceeding of an optical link establishment and the design of wavelength router in the Wavelength Router Optical Network (WRON), an efficient quick dynamic optical link establishment method with quality of service (QoS) is achieved.The main work is described as following:The blocking probability computing model of the WRON is analysized here.And the quick heuristic algorithm for the RWA is studied deeply.Based on it, a quick revised Genetic Algorithm is proposed to solve following problems: the quick wavelength assignment, the quick wavelength converter placement in the network and the quick blocking probabaility computing in link establishment proceeding.And the thesis also does deep research work on how to get a quick low blocking probability router.In the calling and connecting proceeding, the thesis has do some research work on how to cut down the locking time of the leisure resources and how to realize a kind of optical link establishment with QoS by seting the classfication of locking and locking time thresholds.In design of a wavelength router, crosstalk and relay of the wavelength router are analyzed. With combining the above theoretical works in the practical control plane, a wavelength router with total transportation and interchange capacity 960Gb/s and 24 wavelengths with zero blocking probability is realized. And finally, three kinds of optical link establishment are got with a 22 ms quickest link setup time in it.The main achievements in this dissertation are summarized as followings:(1) The performance of the Optical Switch Matrix (OSM) based on the Array Waveguide Grating (AWG) is analysised.Two usful formulas are presented to compute the crosstalk induced by the random phase errors in the AWG device.(2) A novel optical switch matrix structure is proposed in which some small optical switchs are used to replace large optical switches in order to reduce the crosstalk, delay and cost. Comparing with the common stracture, it can reduce the cost to 30%.(3) A formula for computing the blocking probability of a link establishment in the WRON is proposed which is used as the fitness function in the Genentic Algorithm. (4) A kind of variable mutation and crossover rates genetic algorithm (VMCR-GA) for quick Nondeterministic Polynomial-Complete problem (NP-C) solution is proposed. In the VMCR-GA, the rate of mutation and crossover can be adjusted dynamically, which can reduce the blocking probability to 60% and improve the computing speed dramaticlly.(5) A simple dynamic weight Dijistra algorithm connecting with the traffic for the dynamic link path finding is presented which can reduce the blocking probability to 10%-30%.(6) Two rules for reducing the used number of wavelength in the WRON are proposed based on the wavelength relationship graph (WRG) problem----graph color problem which can improve the connect probability to 30%.(7) The calling and connection process is revised by adopting two kinds of resource release mechanisms (Ahead and Timeout Release) which can shorten the proceeding time and reduce the blocking probability to 10%-15%.(8) A kind of simple distributed dynamic optical link establishment method with QoS (Quality of Service) based on setting up three resources-locking time thresholds and the classification of resource is proposed.(9)In order to reduce the proceeding time, a simple integrated control information transportation frame is proposed.