Contention-based limited deflection routing in OBS networks

One of the critical design issues in Optical Burst Switching (OBS) networks is finding ways to minimize burst dropping resulting from resource contention. The existing variants of the basic deflection routing schemes all lack the ability to determine the alternate route based on clear performance objectives. In this paper, we present Contention-Based Limited Deflection Routing (CLDR) scheme, which sequentially performs the following: (1) based on certain performance criteria, dynamically determines if the burst should be deflection routed or retransmitted from source, (2) if the decision is to deflection route, then the same is done using a path that is based on minimization of a performance measure that combines distance and blocking due to contention. Through analytical and simulation modeling, a number of useful insights into the OBS network protocols and performance are provided.