The Research Of Multimedia Ethernet Passive Optical Net

While in recent years the telecommunications backbone has experienced substantial growth, little has changed in the access network. The tremendous growth of Internet traffic has accentuated the aggravating lag of access network capacity. The "last mile" still remains the bottleneck between high-capacity local area network (LANs) and the backbone network. With Ethernet now emerged as a potential optimized architecture for building the next generation access network. The administration of Bureau of Science and Technology of Zhejiang province set the research of multimedia Ethernet passive optical net (EPON) as one of the key projects since last year. This paper is an important part of this project, which is the design and implement of optical network unit (ONU) of the EPON. The main work and the originality of this paper are as follows: The development of access network and Ethernet was introduced; the idea of passive optical network and the concept of combining Ethernet and passive optical network were explained. In these discussions, we mostly discussed the development and prospect of passive optical network based on Ethernet (EPON). The system structure and working principle in our design were introduced; the architectural positioning of EPON was analyzed. We also summarize the frame of MPCP and the key techniques of our EPON system, including dynamic bandwidth allocation, ranging, ONU auto discovery, and etc. After the describtion of our design, then, how to design and implement the ONU were analyzed in detail and the function of each component of ONU was introduced. At last we discussed the workflow of the ONU in FPGA and its arithmetic realization by VHDL programs. Computer simulations of the ONU, the EPON system and the interface were described, and then the results of thess simulations were analyzed, which testified our programs. The advantage and the disadvantage of this EPON system were discussed, and the prospect of EPON market was discussed too.