Optical Packet Switching Edge Node In The System Design And Implementation And Experimental Study

Optical Packet Switching (OPS) is a target of next generation of optical networks. It offers a number of advantages: high data rate, transparency of data format, flexible data allocation, and so on. OPS techniques can be utilised for implementing data transferring and switching between high-speed broadband data networks. Customer service is loaded directly in the form of optical packets. OPS techniques are different from Optical Burst Switching (OBS) techniques due to the fact: for OPS techniques, as a reserved channel is not used for the transmission of a destination address, optical packet signals must include optical labels being used for the switch of optical packet signals. Based on the theory mentioned above, in this experimental system, Multiple Optical Orthogonal Code (MOOC), which is proposed by our research group, is used as an optical label for establishing OPS systems.In this dissertation, discussions are presented of the implementation of edge nodes in OPS systems. The functions of the edge nodes include: 1) transferring customer service data packets into optical payload; 2) generating routing label signals to be sent to label encode module according to the destination address of data packets; 3) after that, generating optical packet signals to be sent to a core node for process and switching; 4) at the same time, receiving the payload signals from the core node, and transferring them into service streams to be sent to customer networks. The design in this dissertation is proposed based on the aforementioned functions.The implementation of edge nodes consists of two parts: hardware and software. In the hardware part, all functions of edge nodes are integrated into a Printed Circuit Board (PCB), in order to avoid the flaws of delay and unstable stability due to bus connections between different modules. In the established system platform, there are several main modules: FPGA modules of core control, allocation circuit modules, interface modules for customer networks, transceiver modules for payload signals, label routing modules, serial interface modules, and so on. In the software part, based on the Nios II processor and free transplantedμClinux embedded operation systems provided by Altera, access of customer networks is implemented, whilst based on the hardware language programming, label routing signals and optical packet signals are generated.Finally, experimental investigations are undertaken of a one-transmitter-two- receivers star network, which consists of three edge nodes and one core node. Such investigations include: access of customer networks, allocation and insertion of label signals, generation of optical packet signals in the three edge nodes, isolation of labels and payload, reception of optical packet signals. In this experimental work, expected results have been obtained successfully.