Study On The Survivability Issue Of Woban Based On Quality Of Recovery

Wireless-Optical Broadband Access Network (WOBAN) is a novel solution for optical access network. Recently, research on the survivability schemes of WOBAN has become an important issue due to the network heterogeneity. In this dissertation, the concept of Quality of Recovery (QoR), which once adopted by the multi-layer optical network, is introduced into the researching area of survivability issues in WOBAN. Besides, the calculation steps of QoR and the theory of network reliability are combined. On the basis of that, the comparison and assessment for both the intra-domain and inter-domain survivability schemes in WOBAN can be achieved. Main works of this dissertation are summarized as follows:Firstly, the QoR concept is introduced, optimized and realized in WOBAN of QoR. Both the network performance parameters such as availability, recovery time, redundancy, and bandwidth of backup path) and the QoR evaluation system are introduced into WOBAN for the first time. Meanwhile, combined with the theory of network reliability and the concept of Quality of Service (QoS), the weighted parameters of QoR are optimized. At last, the calculation of QoR is implemented by the MATLAB software.Secondly, the inter-domain survivability schemes in WOBAN are compared and assessed by QoR. According to calculation process of QoR, four inter-domain survivability schemes including1:1,1:N, Wireless and Wireless&Optical (W&O) are modeled. Then, the simulation of QoR performance for the above four schemes is performed by the calculation program at different network scenarios. At last, simulation results show that the W&O protection scheme has the best optimal performance. The wireless scheme shows its advantage when the network cost is emphasized. And the1:1scheme shows its advantage when the network performance is considered as the primary factor.Thirdly, the intra-domain survivability schemes are compared and assessed in WOBAN. Similarly to the inter-domain schemes, the QoR models of OBOF (Optimizing Backup ONUs selection and Backup Fibers deployment) and MPMC (Maximum Protection with Minimum Cost) are set up. The simulation of QoR performance for OBOF and MPMC schemes at different network scenarios is performed. Simulation results show that the OBOF scheme is superior to the MPMC scheme.