摘 要 近年来,骨干网的能力进一步增强,与此同时接入网方面却没有大的改进。接入网 的能力的增长远远落后于 Internet 流量的快速增长,因而接入网成为高效的 LAN 和骨干 网发展的瓶颈,又被称为“最后一公里”。EPON 由于集中了以太网设备价格低廉和光 纤能够提供高带宽的优点,成为下一代接入网的最佳选择。 本论文首先从接入网的基本概念出发,对接入网的定义与定界和拓扑结构进行介 绍,然后介绍了目前流行的几种宽带接入技术,引出 EPON 接入技术,并对 EPON 技术 的产生背景、网络结构、工作原理和技术特点作进一步介绍;进而从 EPON 业务接入出 发,分析 EPON 系统支持的业务类型以及需求,设计了一套支持多业务的接入解决方案; 最后从 EPON 的应用角度,阐述 EPON 接入网的组网原则,并针对不同类型的用户接入, 最后以某大厦为实例具体设计光线接入到户。
关键词 接入网 EPON 多业务 3网合一
Title Schematic Design Of Broadband Access Network Based on EPON Abstract In recent years,the capability of Backbone Network has been more increased,the access network has not much improvement in the meantime.The rate of increase of capability of the access network is far behind the flow of Internet, so the access network has become the bottleneck of the development of the high efficiency LAN and Backbone Network,and it goes the name of “the last one kilometer”.Due to EPON is a technology with the advantages of the low-price Ethernet equipments and fiber which can provide high bandwidth,it becomes the best choice of the next access network. The article proceed from the basic concept of access network,introduces the definition and demarcation/opological structure of access network,then introduces some Broadband access techenologies that are popular now,to draw the access technology of EPON,and futher introduces the background of generation/ network structure/theory of operation/technique feature of EPON;And proceed from the service access of EPON, analyze the service types and demands which EPON system supports,design a access scheme which can support different services; finally,from the applicationangle of EPON, expatiate the meshing principle,and aim at different kinds of users, separate select campus network/commercial client/denizen user these representative user,base on EPON and use different access technologies, separate design five schemes for campus network/large client or bloc client/medium and small-sized enterprises user/residency user in city and rural user.
Key Words Access Network EPON Different Services Campus Network
光纤接入是指局端与用户之间完全以光纤作为传输媒体的接入技术。光纤接入具有 带宽大、传输距离远、可靠性高等特点,而且光纤接入是实施“少层次、少局所、大局 所”接入网建设原则的最好方式,公认它是宽带接入的发展方向。分为有源光接入技术和无源光接入技术,有源光接入技术主要包括光纤用户环路和 PDH/SDH 等等,其中具有代表性的是上世纪80年代发展起来的 SDH 技术以及后来衍生出来的多业务传送平台(MSTP)技术。 PON 技术是一种点对多点的光纤传输和接入技术,利用无源光器件,采用波分复用和无源光功率分离技术灵活组网。对于无源光网络,目前较为成熟的技术方案主要有 APON 和 EPON。本课题主要研究 EPON 技术,并实现了三网合一,使音频、视频、网络有效的结合到一起,为用户带来了极大的方便。
目 录 1 引言................................................................ 1 2 宽带接入技术分析....................................................1 2.1 接入网的基本概念 ...................................................1 2.2 宽带接入技术分析 ...................................................5 3 基于以太网的无源光网络(EPON)........................................9 3.1 工作原理............................................................9 3.2 技术特点...........................................................11 4 EPON技术在光纤到户中的应用.........................................12 4.1 光纤到户(FTTH)技术 ..............................................12 4.2 EPON系统实现多业务接入...........................................13 4.3 基于EPON 的宽带介入网的设计原则..................................20 5 XX 大厦接入方案设计................................................22 5.1 光纤到户...........................................................22 5.2 FTTH 实施方案.....................................................24 结论 ..................................................................31 致谢...................................................................32 参考文献...............................................................33
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