Study Of The Unequal Outputting Probability Issue In Core Node Of The Optical Burst Switching Network

Optical Burst Switching (OBS) is the promising technology in the field of opticalcommunication exchange. Such a technology not only has the advantages of the opticalcircuit switching and packet switching networks, and more important, through theisolation transmission of the burst packet in time and space, it can make full use of thebandwidth resources via Wave length Division Multiplexing (WDM) to enhance theinternet transmission. To versify such a transmission, this paper investigates themulti-probability outputs of the core nodes in the OBS networks, and then based on theanalysis proposes two techniques to reduce the congestion rate of the Burst DataPackets (BDPs).This paper, first of all, reviews the principles, structures and other related techniquesof the OBS network, and then focuses on the multi-probability outputs of the core nodes.Experiments are conducted to examine the multi-probability output models.Experiments are also done to analyze the changes in the congestion rate of BDPaccording to the grade of services.Next, to efficiently reduce the congestion rate of BDPs and maintain the quality ofservice, this paper integrates the optical buffer technology, deflection routingtechnology and segmentation technology employed in the equal probability outputs, andproposes two new techniques to be used in the cases with the multi-probability outputs.One is the optical buffer technique, which caches the BDPs that could cause potentialcongestion by utilizing the features of fibre delay lines. The results show that such atechnique can reduce the congestion rate of BDPs to some extent and at the same timeensure the passage of BDPs with high priority. The other is the deflection port technique.The notion of segmentation before deflection can guarantee the passage of BDPs withhigher priority and also relieve the possible network delay in the whole BDP caused bythe deflection. In this way, the second technique can achieve the goal of reducing thecongestion rate of BDPs.In the cases of multi-probability outputs, the proposed two techniques can to adegree enhance the transmission performance of BDPs, improve the quality of servicesand better utilize the bandwidth resources. It can also reduce the congestion rate ofBDPs and minimize the cases where BDPs may be discarded due to the congestions.