Research On The Key Control Techniques And Passive Optical Devices In The Automatic Switched Optical Network

An Automatic Switched Optical Network (ASON) is an intelligent optical transport network. By introducing standardized protocols including signaling, routing and link management, the intelligentalization of the optical transport network is the realization of automatic service discovery, automatic connection establishment and automatic failure restoration. This paper focuses on the control techniques and passive optical devices in ASON with a deep and innovative research in the following areas:Optical User Network Interface (UNI): A new control plane recovery mechanism is proposed against UNI ingress nodal failure. The theoretical estimation and experimental results show a reduction of recovery time.Dual-homing configurations on UNI clients: A complete end-to-end diversity path service is offered in our proposed mechanism. This mechanism gets better accommodation with current standards, and enables higher security level of the vendor's network.Multi-domain ASON and hierarchical routing techniques: A genetic algorithm based bi-directional shuffle-net topology aggregation method is proposed. Simulation results show that the proposed topology scheme produces a more accurate virtual topology and is very suitable for large-scale optical network for its scalability. In addition a lazy re-aggregation policy is proposed to control the frequency of topology re-aggregation. This policy reduces the dispatched link state update messages over control channels, without decreasing the routing performance significantly.A 31×11×5mm~3 direct-coupled fiber switch and a sub-millisecond optical switch array are reported. Finite element analysis is conducted in structure design and optimization stage. The devices are developed by micro-machining techniques. Performance test shows that both the insertion loss and switch time meet the design expectations.A micro-machining based electromagnetic-driven variable optical attenuator is developed. Attenuation is introduced by a rotable miniature silicon mirror, with its orientation finely adjusted through the balance between a pair of electromagnetic force. The design is free of conventional spring restoring force for attenuation reset and therefore ensures a high stability.