Traffic Grooming In Optical WDM Networks

In optical wavelength division multiplexing networks, sub-wavelength traffic streams can be elaborately arranged in wavelength channels to minimize the total cost of the network construction, known as traffic grooming problems. In this dissertation, the grooming problems of arbitrary traffic in optical WDM networks are studied using genetic algorithms, including the following aspects. (1) A genetic algorithm is proposed to solve arbitrary traffic grooming problems in unidirectional rings. A variety of crossover and mutation operators is compared by numerical simulation, and the optimal parameter values of the genetic algorithm are achieved. Enhanced decoding methods are proposed, which can greatly improve the performance of the genetic algorithm. (2) Based on above work, the genetic algorithm is simplified and "the best survive" strategy of selection procedure is introduced. Bidirectional decoding and pre-optimization of chromosomes are proposed to further improve the genetic algorithm. Local optimum of the permutation-based chromosomes is defined, and a hill-climbing algorithm is proposed to get the local optimum. (3) A new genetic algorithm is proposed to solve arbitrary traffic grooming problems in mesh networks using the permutation-based chromosome representation. The term "mixed topology" is defined for routing of traffic streams. Fission of the chromosomes is proposed in the decoding procedure. Routing streams with various link costs and different selection strategies are compared. Some RWA problems are also solved using the proposed algorithm.In this dissertation, the management of optical networks is also studied, including network element management system and network management system. A management system is implemented for an optical network testbed with configuration, performance and fault management function, using outband IP network as signaling network. The management plane and the interface for management of the transport plane in an automatically switched optical network testbed are studied, by which the permanent connections can be set up. A scheme of the management plane in hierarchical routing networks is designed.The dissertation includes some other aspects, which are: optical add-drop unit implemented in optical add-drop multiplexer and optical cross connect equipments for Chinese Advanced Information Network (CAINONET); tri-directional transportation experiment, in which the deterioration of the signal induced by Rayleigh scattering of other wavelengths is studied.