Obs Network Traffic Grooming Key Technologies

Optical Burst Switching (OBS) has become a key topic in the research area of optical transmission technology as a novel solution to realize IP-over-WDM. Combining the advantages of optical packet switching (OPS) and wavelength routing (OCS) while eliminating the drawbacks, it is widely expected to be the core technology for the new optical network.Due to the huge cost of optical transceiver presently and the limitation of core node function (lack of optical buffering resource, long responding time for configuration of optical transmission matrix, etc.), three main traffic grooming problems need to be solved urgently, including bandwidth fair assignment of traffic stream, improvement of the switching efficiency of core node and economy of limited OBS network source. Currently, these traffic problems have become the new hot research subject in the OBS network. However, as this research is still at the beginning stage, lots of relative principles remain unclear. According to the key theories and technical problems of traffic grooming in OBS network, this dissertation researches into the shaping of traffic streams and the burst grooming theories closely. Some new algorithms and strategies are presented to overcome the disadvantages found in previous researches. The innovative points are listed bellow:(1) In order to solve the fair transmission problem of multi granularity static traffic streams in optical burst switching network, a forward resource reservation scheme based on traffic bandwidth constrains (FRR-BC) is proposed. FRR-BC scheme predicts the length of data burst and updates the maximum length threshold of burst assembling according to the bandwidth change of static traffic streams. Via the theoretical analysis and simulation, it shows that this scheme implements the bandwidth fair assignment, and effectively lowers the latency of data burst. Furthermore, concerning the traffic shaping, FRR-BC provides more efficient statistical multiplexing of network resources.(2) A novel burst grooming scheme without FDL is propounded without introducing any extra burst buffering delay. A new control signal protocol and channel schedule algorithms (BGUC) are defined. BGUC-DS for supporting Diffserv is also specified. Simulation verifies that this burst grooming scheme improves the switching efficiency of core node and achieve a lower packet loss probability, while introducing no extra burst delay.