New Broadband Access Technology And Application Based On EPON

FTTH (Fiber to the Home) is the optical network unit (ONU) installed on the home user or business user, is a FTTx access, is the closest to the user's application of the type of optical access network. Along with video, digital TV, IPTV bandwidth multimedia applications such as the popularity of large commercial customers for network bandwidth demand to increase the stability of the domestic FTTH for the discussion of the gradual warming, the market demand for increasingly lower cost, as well as an unprecedented historical opportunity, FTTH is being promoted in China, at the same time, with the gradual maturity of PON technology, particularly EPON (EthernetPassiveOpticalNetwork) is the PON technology in the most mature technology, the most widely used one by IEEE802.3EFM (EthernetfortheFirst Mile) Put forward. It is its low cost, simple maintenance, easy expansion, easy upgrade, to provide very high bandwidth services, bandwidth allocation and flexible, making FTTH may be a business and become the next 4 to 5 years of China's telecom industry development The new bright spot.The so-called Optical Access Network (OAN) is used as a major fiber-optic transmission to replace the traditional media's twisted-pair access network, refers to a local or remote switches module exchange between the user and the use of fiber-optic communications or in part, using fiber-optic communications systems [ 4]. From optical access network definition, we can see that under normal circumstances, OAN is a point-to-multipoint optical transmission systems. According to the outdoor access network transmission equipment contain the source of equipment, OAN can be divided into passive optical network (PON, Passive Optical Network) and Active Optical Network (AON, Active Optical Network). PON fiber-optic lines from the main terminal (OLT), fiber-optic distribution network (ODN) and optical network unit (ONU) component. OLT switch interface with the functions of the completion of the downlink power to light up the conversion of light into electricity, as well as the distribution channel and control the connection, and monitor the implementation of the various optical interfaces, to provide control, maintenance and management functions. PON is the use of passive optical signals Fenzhi Qi will be distributed to users using passive optical Fenzhi Qi smaller initial investment, but necessary to adopt a better performance, wide bandwidth optical equipment.EPON is the use of so-called passive optical network (PON) topology of the realization of carrying a variety of business Ethernet signal transmission in the form of a network, that is, the PON fiber-optic transmission of the changes in the length of the Ethernet frame signal, the basic principles of APON with a similar structure and G. .983 on the basis of trying to retain the essence of the APON - physical layer PON, and Ethernet to replace the ATM as a data link layer protocol. So as to provide a greater bandwidth, lower cost and wider operational capacity of the new combination.Using point-to-multipoint EPON structure of the passive optical transmission method in Ethernet provides a wide range of business. Currently, IP / Ethernet LAN communications applications as a whole accounted for 95%, EPON due to the use of the above-mentioned economic and efficient structure, making it the access network to connect end-user of one of the most effective communication methods. 10Gbit / s Ethernet backbone and metro ring is also the emergence of EPON will be the next best all-optical network in the last mile solution.A typical EPON system by the OLT, ONU / ONT, POS components. As shown in Figure 3-4 [27]. OLT at the root through the ODN connected with the ONU, in the downlink direction, OLT for the provision of passive optical fiber network interface; in the upstream direction, OLT will provide GE (Gigabit Ethernet). In the future 10Gbit / s Ethernet technology standard after the stereotypes, OLT will also support a similar high-speed interface, in order to support other popular agreement, OLT can support ATM, FR, as well as OC3/12/48/192 such as the rate of SDH / SONET The interface standard. OLT through the E1 interface to support traditional TDM voice of the access. EPON in a unified network management side, OLT is the main control center and network management to achieve the main function. POS (Passive Optical Splitter) is a passive optical Fenzhi Qi is a connection OLT and ONU passive devices. ONU resident on the user side, the end-user access [10].EPON is some of the best technology and network structure of the combination. On the current terms, EPON is the most comprehensive and mature PON technology, mainly in the following areas:7. EPON technology is relatively simple and easy to achieve, after (China Telecom) to improve business standards, has reached the level of carrier-class;8. EPON chip business has matured, the number of commercial equipment and more patterns in the basic functionality and performance, the ability to support the operations and maintenance management capabilities in areas such as China Telecom has been able to meet the network and business requirements;9. EPON chip level and system-level exchange of large-scale and fully realized;10. EPON abroad has been the order of millions of commercial scale;11. China Telecom in the field test in EPON equipment has been stable operation for more than a year and a half;12. EPON further mature industry chain formed a pattern of healthy competition in the market, a further decline in the cost of equipment.Due to the above technical advantages, EPON upon by the emergence of a large number of equipment manufacturers favor, EPON optical network access system with rapid deployment of flexible, multi-service, access to high-performance, high cost performance. Therefore, is recognized as a fiber-based broadband access technology ideal one. EPON combination of theory study, the authors of the actual work of university teachers in Liaoning Petrochemical apartment access Campus Network Planning and Engineering program has been studied, with several traditional access comprehensive contrast, investment in equipment, fiber optic cable investment , As well as the construction of multi-subsequent maintenance point of view, a final decision on this project using EPON access methods. The villa district users on the use of optical fiber to the home, and on the high-level users and the number of apartment building fiber-to-access manner.Then, combined with the specific conditions of teachers in the apartment, through the theory of knowledge-based EPON and rational design of the network topology, the formation of a viable, the project's scientific program. And in accordance with the guidance of the program, the deployment of engineering, equipment installation, testing equipment such as concrete work. And the actual construction process, the solution to the scene of the existence of other issues, the successful completion of this project, and passed the inspection. Through a variety of professional testing, inspection of the project design to satisfy technical requirements. The pilot project FTTH system with a capacity of 40, building to test fiber-optic system capacity for 958, equipment with a total investment of 350,000 yuan for each line of equipment costs 350 yuan (not including the cost of fiber optic cable) has been well below normal LAN Access. At present, users have access to open 400 users over a period of time, well, each household bandwidth of more than 30M, faster than ADSL for nearly 20 times. This is the first city of Fushun in the true sense of the FTTH trial network for the next large-scale commercial and accumulated valuable experience.To sum up, fiber to the home user to provide broad access to the rich, this is a great temptation to access fiber-optic technology the driving force of development and maturity. Through access to fiber-optic technology development in the history of research, through a variety of fiber-optic access technology analysis, we can come to EPON technology is mature and broad prospects for application should be to promote business.