Research On OCDM Based Optical Label In Optical Packet Switching

With the wide scale deployment of WDM network, the need for greater transmission capacity has been met. But in switching nodes, the optical data needs a photoelectric conversion. The mismatch between the transmission capacities offered by the WDM optical layer and the processing power of switching becomes a bottleneck, which restricts the performance of network applications. Optical label switching comes from optical packet switching which uses the low-speed label signal to make the routing choice and switching control, while retaining the high-speed characteristics of optical switching. It is a promising way for the future optical switching. Using optical label based on OCDM can achieve all-optical label processing without photoelectric conversion, which is faster than others. OCDM based label switching also has a great advantage on both technical and economic aspects by using simple optical devices.In this paper the main research is the application of OCDM based optical label in optical packet switching, to achieve the all-optical label processing in the core routing nodes. The development of OCDM label is presented. The network and the key technology of optical packet switching using OCDM labels are introduced. The structure of prime codes, extend prime codes, and second prime codes as well as their correlation characters are simulated and compared. The implementation of the optical codes is studied, with emphasis on the principle of the Fiber Bragg Grating as label encoder. Through the simulation of the optical switching system using OCDM labels, we demonstrated the system model and studied the performance of the system. To improve the problem of high splitting loss during label recognition in the node, a switching scheme which uses multiple OCDM codes as a label is proposed and simulated. To overcome the problem of complex OCDM label swapping, a label stacking scheme using dual-stage-coding optical code labels is proposed and demonstrated, which avoids the label swapping by using the label stack and ensures the correct extraction and recognition of each label from the label stack by dual-stage coding. The scheme is proved by simulation.