Data Link Layer And Onu In The Epon System To Achieve

EPON access network technology is an important technology and represents the future development direction of FTTx technologies. However, due to technical standards for the definition of imperfections in the current EPON applications, there are many problems. Especially, interworking between different equipment manufacturers is a big one. In a large extent, this prevents the large-scale application of EPON.First of all, based on the research and analysis of IEEE Standard 802.3ah-2004 EPON technology, EPON system data link layer protocol is analyzed in detail. EPON structure, protocol stack, communication process and multi-point control protocol is described particularly. And then several key technologies in data link layer are introduced: ranging, uplink bandwidth allocation, multi-service QoS guarantee and security issues.Secondly, based on EPON System Development Project for background, ONU scheme design and ONU hardware realization are discussed. In ONU scheme design, there is a detail analysis and comparison between single-LLID/ONU and multi-LLID/ONU. These two programs also contribute to one of the main reasons for interoperable of EPON equipments. The comparison is from uplink bandwidth utilization, multi-service QoS guarantee and network management. According to different user port style, ONU is divided into pure data ONU, voice/data ONU and three nets ONU. Finally the realization of pure data ONU with multi-LLID/ONU scheme is described in detail. And preliminary test results show that the ONU realization is success.Based on the detailed analysis of the EPON system data link layer protocol and project background, analysis and comparison of the two main programs of ONU realization, described the project options and the reasons, and then its concrete realization, this thesis is a valuable reference for EPON system development in the future, and especially in the realization of ONU.