Study On The Congestion Control Schemes In Optical Burst Switching Network

Optical burst switching network is one of the most promising solutions for the high-speed and vast-bandwidth switching network in the future. And congestion control schemes which are one of the key techniques in the current study become the essential step in the process of deploying the OBS network. In this thesis, the congestion control schemes had been extensively addressed from the point of view of three aspects. They were the OBS edge node layer, the OBS core node layer as well as the survivability of OBS network. Besides, how the key techniques in OBS network impact on the congestion control was also discussed. Moreover, several key techniques were implemented by means of Field Programmable Gate Array (FPGA).Contributions and numerical results of this dissertation are as follow:Firstly, the congestion control schemes adopted in the OBS edge node layer were addressed and the corresponding algorithms were simulated and discussed. 1) A design of network interface card which named as OBS-Ethernet was proposed for full-duplex exchanging the data between the OBS and Ethernet. 2) A self-tuning assembly algorithm which based on the feedback of burst size was devised. 3) The performance of Random Early Detection (RED) and its two variants were simulated and compared in the circumstance of queue management for OBS network. 4) A scheduling algorithm for data channels which modified by Preemptive Prioritized Just Enough Time (PPJET) protocol was given.Secondly, the congestion control schemes adopted in the OBS core node layer were addressed and the corresponding algorithms were simulated and discussed. 1) A novel optical structure of Optical Cross Connection (OXC) was designed for the OBS core node. In addition, both the wavelength congestion analysis and control algorithm for the new OXC were devised. And the simulations of the optical parameters for the OXC had done. 2) A control algorithm named as Additive Increase Multiplicative Decrease control with the Number of Burst Control Packet (AIMD-NBCP) is devised for improving the deflection routing of OBS network. 3) The performance of two wavelength conversion schemes, First-Fit (FF) and Nearest Wavelength First (NWF), were simulated and compared. 4) A load balancing algorithm based on the concept of Load Distribution Variance was proposed for the OBS networks. Thirdly, the survivability of OBS network was addressed in terms of the feasibility and performance of Bidirectional Forwarding Detection (BFD) adopted by OBS network. 1) The detection process as well as the packets exchanging process of was given when the BFD was used for detecting the node failure and link failure at the asynchronous mode. 2) The deployment procedures of BFD in the OBS network as well as the process of failure localization for fiber failure, link failure and node failure were given. 3) Simulations on the effectiveness and detecting ability of BFD for the failure detection and localization were done.Finally, several key techniques were implemented by means of FPGA. 1) The FAS (Fixed Assembly Size), FAP (Fixed Assembly Period) as well as MBMAP (Max Burst Size Max Assembly Period) assembly algorithms were implemented. 2) The LAUC (Latest Available Unscheduled Channel) scheduling algorithm for data channels was implemented. 3) The JIT (Just In Time) and JET (Just Enough Time) resource reservation protocol were implemented. 4) Four types of framework such as Hello, Link State, Link State Database and corresponding acknowledgements were implemented. So were the transmitting and data exchanging of these four frameworks.