Routing in WDM rings and multi-ring networks

A stacked ring design was advocated for the designing economical WDM ring networks and an algorithm was presented which confirmed the possibility of the cost-effective dimensioning of ring networks to meet demand growth. Two variants of the stacked ring design heuristic was described with Algorithm B yielding those designs requiring the fewest nodes. The described scheme can also be adapted for the design of shared-protection SDH rings with time-slot interchange (TSI) capability. In such rings, a load-balancing scheme can be employed to fully utilise the available bandwidth of the ring. Because each ring in the stack can vary in size, simple node/ring additions should be possible enabling the network to be cost-effectively augmented to meet further growth in demands. These heuristics offer simple real world implementations and their fast execution times lend to their implementation as frequently called routines in network design tools