The Study On Key Technologies Of Optical Burst Transport Network

The continuous increasing of data services proportion in the network traffic proposes the new challenges and requirements to the metro and backbone network transmission. Existing transmission scheme for MAN is generally based on SDH/OTN optical transport network. Althrough this network architecture can support the transmission of Ethernet business, the completion of data transmission and switching is still in the electric layer, with high the photoelectric conversion energy consumption and low wavelength utilization, lacking of flexible and dynamic resource allocation capabilities. Optical Burst Transport Network (OBTN) based on Optical Burst mode refines the transmission granularity for achieving statistical multiplexing of bandwidth resources in the optical layer, and due to its unique ring network topology, it has unique advantage in protection switching mechanism, and supporting full mesh network logic, thus it is very suitable for the deployment of MAN. As an important stage in the evolution of all-optical network, Optical Burst Transport Network is of great significance in researching.The paper carries out a deep research about optical burst transport network on key technologies such as signaling control protocol and resource scheduling mechanism. The main contents are displayed as follows:1. In this paper, OBTN transport mechanism based on slot transmission and fixed transmitter tunable receiver wavelength tuning equipped with centralized control mechanism is designed. On this basis, the corresponding various types of frame structure and node structure is designed. It is elaborated*that transmision mechanism of business crossing the master node are proposed. We also design a complete ranging mechanism used to obtain the correct network topology and critical system parameters. The system can work stably and efficiently with these mechanisms memtioned above.’2. The bandwidth allocation algorithm based on the resource scheduling mechanism is proposed. A bandwidth authorized map comes out from bandwidth request after two steps. They are clipping algorithm based on trying authorized strategy and authorized configuration algorithm based on the minimum degree of overlap first authorized bandwidth. Simulation demonstrates that the authorized configuration algorithm can achieve lower than0.5%unsuccessfully configure ratio of the bandwidth map.3. We structures OPNET-based OBTN simulation platform, integrating with the key mechanisms and algorithms. We also build ON/OFF model to simulate the self-similar traffic stream to analyse and evaluate system performance. We analyse the network performance on different burst lengths, resource scheduling cycle, packet length and DBA cycle. Simulation results show that the resource scheduling mechanism and algorithms enable the system to achieve a lower loss ratio than system working in fix bandwidth allocating among the whole network, and improve by27%bandwidth utilization rate when inputing a highly-bursty data source.