The Network Arichitecture And The Traffic Grooming Of Optical Burst Switching

The Optical Burst Switching (OBS) is considered as the promised optical switching technology for the gigant bandwidth demands of the internet backbone network, for OBS combines the advantages and overcomes the most disadvantages of the Optical Packet Switching (OPS) and the Optical Circuit Switching (OCS). This dissertation studied the network architectures and the routing technology and wants to decrease the requirements to the optical apparatus by constructing more proper network architecture and routing technology. Concretely speaking, the abstract of the dissertation is as follows.1. Solve the burst dropping in the OBS ringThe biggest obstacle to the practical using of the OBS is the high burst loss rate. Besides the great gap between the expectation and the capability of the optical apparatus, the enviroment that we want the immature OBS to face is too complicated is another reason that causes the high burst loss rate.Ring is the most popular topology for the communication networks. In the ring, the burst contention is not as drastic as the mesh network. And several intersect or tangency rings can perform as a mesh network. So consider to solve the burst dropping in the ring before the mesh would be more feasible.We proposed a local data burst uploading strategy in the OBS ring. By the strategy, an optical buffer depth about a burst is enough for solving the burst contention in the OBS ring, which make the requirement for the optical buffer approach the limit to solve the burst contention in an asychronous burst switching network. We studied the burst loss rate by the theory analyize and the simulations, and the results show that we can decrease the burst loss rate to a neglectable level easily.2. The OBS ring architecture design We proposed an OBS network architecture, called resilient optical burst ring (ROBR). For we can solve the burst dropping in an OBS ring basing on the optical buffer, design a OBS ring consulting the successful asynchronous packet switching ring is possible. The ROBR is derived from the IEEE802.17 and inherits the most advantages of the IEEE802.17 such as the high bandwidth utilization, resilience, fairness in bandwith allocation and etc. We studied the ROBR by the theoretic analysis and simulations, and the result shows the ROBR has much better performance than the central switching OBS ring.3. The realization of OBS meshThe ring topology is not enough, considering about the fiber resource, the network administration, the interconnection between the carriers, and other confine in the practical application envirmonents. If want to be a successful solution to the core network, the resilient optical burst ring should be evolved to the resilient optical burst mesh (ROBM). We design the bridge node for the ROBR, by which several ROBR can be bridged together to be ROBM. ROBM inherits the merits of ROBR, such as bursts loss free, high bandwidth utilization, resilience, and etc. Then we can construct the hiberarchy networks or peer networks by ROBM easily.4. The traffic grooming in the OBS/OPS networksThe traffic grooming in the WDM network is a hot spot problem rescently. The OBS/OPS networks have the wavelengths and the subwavelength traffic as the WDM networks. Gather subwavelength traffic to wavelength properly and switching the wavelength instead of the subwavelength traffic would get better performance. In this dissertation we proposed a shortest path first routing protocol based on the virtual nodes that the source node in the OBS/OPS network could choose the proper wavelength to upload the traffic and the bursts or optical packets could be gathered as a wavelength in a certain intermediate node to be switched. So the burst/packet loss rate could be decreased by the possibility of contention is decreased.