Optimal routing for minimum wavelength requirements in end-to-end optical burst switching rings

A novel routing and link dimensioning optimisation method which minimises the total wavelength requirements of dynamic optical WDM rings-the most popular topology in metropolitan networks- is proposed. The method finds the solution (set of routes) of minimum cost by solving an integer linear optimisation problem. Contrary to the common belief, results show that the optimal routes found by the proposed method are not necessarily balanced and that significant wavelength savings are achieved compared to the usual balanced-load routing approach in rings. This makes the proposed method the best choice for implementation in future dynamic WDM ring networks.