Considerations on In-Band and Out-of-Band Signalling Constraints in OBS Networks

Most of previous works on Optical Burst Switching (OBS) assume in their analysis that signalling does not affect network performance. In this paper we analyze under which conditions the effect of signalling is actually negligible, taking into account the effect of signalling in the evaluation of burst discard probability. We use two analytical models for two different signalling techniques in an OBS network: out-of-band and in-band technique. We evaluate the impact of these two signalling strategies in term of the probability of burst discard. We also discuss a new method to assign the correct amount of resources to the control plane. To verify the accuracy of the proposed models, analytical results are compared with results based on discrete-event simulations and are found to be in very satisfactory agreement.