Due to the rapid development of broadband access technologies, the broadband access networks have wider and wider application. However, with the development, the security issue became a public concern. Under the envir...Due to the rapid development of broadband access technologies, the broadband access networks have wider and wider application. However, with the development, the security issue became a public concern. Under the environment of access network, customers, access equipment and networks all face various threats, especially those from the user side. Such technologies and solutions as port positioning, fraud prevention on Medium Access Control (MAC) addresses and monitoring of illegal services might be the solution to the security problem existing in the current networks.展开更多
This paper presents the design and implementation of access controller used for Ethernet passive optical network （ EPON）. As a first step to develop an ASIC product, the entire system is designed on a field programm...This paper presents the design and implementation of access controller used for Ethernet passive optical network （ EPON）. As a first step to develop an ASIC product, the entire system is designed on a field programmable gate array （FPGA） with an embedded CPU. To reduce working frequency of the FPGA, the byte-to-word conversion is proposed. Propagation delays are equalized by ranging procedure so as to avoid data collision. Implementations of synchronization, classification, as well as Linux porting are illustrated in detail. The interface between the FPGA and CPU are also presented. Experimental results show that the proposed system can properly function in a relatively low cost FPGA.展开更多
为优化光纤传输质量,满足宽带接入的可控化管理需求,要严格遵循光纤传输应用控制的技术规范,有效建立基于光传送网(Optical Transport Network,OTN)技术的光纤传输接入网络,从而维系信息传输的及时性,搭建完整的技术运行框架。应从大颗...为优化光纤传输质量,满足宽带接入的可控化管理需求,要严格遵循光纤传输应用控制的技术规范,有效建立基于光传送网(Optical Transport Network,OTN)技术的光纤传输接入网络,从而维系信息传输的及时性,搭建完整的技术运行框架。应从大颗粒信息传输处理、城域核心网和干线网络、宽带用户接入、长途网应用交叉设备等方面对OTN技术的具体应用内容进行系统化分析,更好地实现网络性能的平滑升级,从而满足城域网建设的具体需求。因此,系统研究光纤传输接入网络中OTN技术的应用要点具有现实意义。展开更多
The planning of wireless communication networks in underdeveloped countries is studied for landline telephone, fixed broadband wireless access and PLMN systems via investigation and discussion of the LDC networks＇ ch...The planning of wireless communication networks in underdeveloped countries is studied for landline telephone, fixed broadband wireless access and PLMN systems via investigation and discussion of the LDC networks＇ characteristic, technology selection, deployment consideration, network configuring, civil work evaluation and investment estimation. An example is embedded all through providing a general展开更多
We demonstrated a unified two-band broadband light source based on erbium-doped fiber. The proposed scheme generates high output power at both bands and saves doped-fiber and pump lasers.
千兆无源光网络(Gigabit Passive Optical Network,GPON)技术在宽带接入网中具有广泛的有效应用。首先介绍了GPON技术的基本原理,包括光纤传输基础知识、GPON网络结构以及下行上行传输机制。其次探讨了GPON技术的应用优势,如高带宽和高...千兆无源光网络(Gigabit Passive Optical Network,GPON)技术在宽带接入网中具有广泛的有效应用。首先介绍了GPON技术的基本原理,包括光纤传输基础知识、GPON网络结构以及下行上行传输机制。其次探讨了GPON技术的应用优势,如高带宽和高速率、长距离传输能力、共享网络资源以及低成本和高效率。最后介绍了GPON的应用模式,包括光纤到户(Fiber to the Home,FTTH)和光纤到楼(Fiber to the Building,FTTB)等。在此基础上,详细阐述了GPON技术在宽带接入网中的应用,包括提供高速宽带接入、支持多种业务和服务、实现高质量的视频和音频传输以及支持远程办公和云服务。另外,展望了GPON技术的发展趋势和未来展望,GPON技术在宽带接入网中发挥着重要的作用,并具有广阔的应用前景。展开更多
文摘Due to the rapid development of broadband access technologies, the broadband access networks have wider and wider application. However, with the development, the security issue became a public concern. Under the environment of access network, customers, access equipment and networks all face various threats, especially those from the user side. Such technologies and solutions as port positioning, fraud prevention on Medium Access Control (MAC) addresses and monitoring of illegal services might be the solution to the security problem existing in the current networks.
基金Project supported by Science Foundation of Shanghai Municipal Commission of Science and Technology (Grant No .04dz12045)
文摘This paper presents the design and implementation of access controller used for Ethernet passive optical network （ EPON）. As a first step to develop an ASIC product, the entire system is designed on a field programmable gate array （FPGA） with an embedded CPU. To reduce working frequency of the FPGA, the byte-to-word conversion is proposed. Propagation delays are equalized by ranging procedure so as to avoid data collision. Implementations of synchronization, classification, as well as Linux porting are illustrated in detail. The interface between the FPGA and CPU are also presented. Experimental results show that the proposed system can properly function in a relatively low cost FPGA.
文摘为优化光纤传输质量,满足宽带接入的可控化管理需求,要严格遵循光纤传输应用控制的技术规范,有效建立基于光传送网(Optical Transport Network,OTN)技术的光纤传输接入网络,从而维系信息传输的及时性,搭建完整的技术运行框架。应从大颗粒信息传输处理、城域核心网和干线网络、宽带用户接入、长途网应用交叉设备等方面对OTN技术的具体应用内容进行系统化分析,更好地实现网络性能的平滑升级,从而满足城域网建设的具体需求。因此,系统研究光纤传输接入网络中OTN技术的应用要点具有现实意义。
文摘The planning of wireless communication networks in underdeveloped countries is studied for landline telephone, fixed broadband wireless access and PLMN systems via investigation and discussion of the LDC networks＇ characteristic, technology selection, deployment consideration, network configuring, civil work evaluation and investment estimation. An example is embedded all through providing a general
文摘We demonstrated a unified two-band broadband light source based on erbium-doped fiber. The proposed scheme generates high output power at both bands and saves doped-fiber and pump lasers.
文摘千兆无源光网络(Gigabit Passive Optical Network,GPON)技术在宽带接入网中具有广泛的有效应用。首先介绍了GPON技术的基本原理,包括光纤传输基础知识、GPON网络结构以及下行上行传输机制。其次探讨了GPON技术的应用优势,如高带宽和高速率、长距离传输能力、共享网络资源以及低成本和高效率。最后介绍了GPON的应用模式,包括光纤到户(Fiber to the Home,FTTH)和光纤到楼(Fiber to the Building,FTTB)等。在此基础上,详细阐述了GPON技术在宽带接入网中的应用,包括提供高速宽带接入、支持多种业务和服务、实现高质量的视频和音频传输以及支持远程办公和云服务。另外,展望了GPON技术的发展趋势和未来展望,GPON技术在宽带接入网中发挥着重要的作用,并具有广阔的应用前景。
