Epon Mac Protocol Research

Nowadays, Ethernet Passive Optical Network (EPON) as a competitive solution for the first mile of FTTH (Fiber to the Home) is becoming more and more popular. Due to its prominent advantages, such as big capacity, low cost, easy maintenance, high compatibility, easy upgrading, and so on, EPON will become one of the most important technologies for broadband access network in the future.In order to satisfy typical topology structure and hardware configuration, we introduce a basic protocol for media access control (MAC) layer of an EPON to realize distance measuring and dynamic bandwidth allocation (DBA). Furthermore, we propose some novel algorithms for inter-ONU (between different ONUs) and intra-ONU (between differentiated services in an ONU) scheduling. Considering the reliability and protection in an EPON, we also introduce some novel protection scheme against link failures in the MAC layer.In chapter 2, the basic architecture and components of an EPON are analyzed, and the key of the bandwidth allocation algorithm based on the GATE/REPORT mechanism is discussed. The corresponding program is compiled in the Visual C++ .NET environment, and technologies of the interface and multithreading program are applied. In the basic protocol, the handshaking information is exchanged between subscribers and central office, and then DBA algorithm is realized by updating polling table.After analyzing existed algorithms of inter-ONU scheduling and intra-ONU scheduling in chapter 3, we introduce some novel algorithms for the EPON. Comparing the simulation results, we can prove the performance, such as throughput, delay, fairness, priority and so on, is much better than before.Some protection schemes in EPON against link failures between OLT andremote node (RN) and RN and ONUs are provided in chapter 4. The basic protocol in MAC layer with a small modification can support proposed protection schemes in physical layer. Availability and performance of protection scheme are proved by simulation results.Finally, the conclusion is drawn, and the corresponding work is very helpful for the future.