We present an analytical model to study the multiclass-traffic-based optical burst switching system. In contrast with the previous on-off burst arrival process model, which is based on a single class of traffic and depends on just one probability of bursts to choose output ports, in our scheme we evaluate the blocking probability for multiclass bursts at the core router, which chooses output ports depending on differential probability, and we give some useful discussion for the design of real optical burst switching networks.
With the development of all-optic network, the research of all-optic wavelength routing technology becomes a hot subject in all over the world. In this paper a new structure optical wavelength router which is feasible in the reality is proposed whose main advantage is having no tunable components and converting multiple wavelengths simultaneously. The proposed design is very similar to a traditional wavelength router structure, but the difference is in two fold. First it uses fixed wavelength converter. This converter converts any input wavelength to fixed wavelength. Second it allows loop back of the light. With this allowance of loop back, we can achieve the ability of tunable wavelength converter using fixed tuned wavelength converter. In comparison with previously reported structures, our design has the advantage of its simplicity and low-cost. The all-optic router prototype is experimentally tested in a small 3X3 network with a STM-16 bit stream per channel.
Ant colony algorithm (ACA) is a novel simulated evolutionary algorithm. It is a population-based approach, which allows positive feedback to be used as the primary search mechanism and provides a new method for complicated combinatorial optimization problems. In this paper, it is used to optimize restoration routing for WDM optical networks. It is improved in three parts of selection strategy, local search, and information modification and it can process the problem of optimal restoration route search for different purpose in the cases of various failure conditions. Through the numerical results of practical networks: CHINANET, the practicability has been proved.