Fault Tolerant Congestion based Algorithms in OBS Network

In Optical Burst Switched networks, each light path carry huge amount of traffic, path failures maydamage the user application. Hence fault-tolerance becomes an important issue on these networks.Blocking probability is a key index of quality of service in Optical Burst Switched (OBS) network. TheErlang formula has been used extensively in the traffic engineering of optical communication to calculatethe blocking probability. The paper revisits burst contention resolution problems in OBS networks. Whenthe network is overloaded, no contention resolution scheme would effectively avoid the collision andcause blocking. It is important to first decide, a good routing algorithm and then to choose a wavelengthassignment scheme. In this paper we have developed two algorithms, Fault Tolerant Optimized BlockingAlgorithm (FTOBA) and Fault Tolerant Least Congestion Algorithm (FTLCA) and then compare theperformance of these algorithms on the basis of blocking probability. These algorithms are based uponthe congestion on path in OBS network and based on the simulation results, we shows that the reliableand fault tolerant routing algorithms reduces the blocking probability.