Wedding……

兄弟结婚了，朋友结婚了，朋友的朋友结婚了；男的结婚了，女的结婚了，不男不女的也结婚了；有感情的结婚了，没感情的结婚了，认识不认识的结婚已经无所谓了……     

Internet防火墙及其发展趋势

本叙述了Internet来自外部，内部，硬件，软件方面的十种安全威胁和攻击，给出了防火墙的限制，隔离，筛选，过滤和屏蔽作用，介绍了防火墙的六种基本结构类型，论滤了过滤路由器，双宿主主机，主机过滤，过滤子网和吊带式五种安全结构，分析了传统防火墙的七种不足，给出了目前防火墙混合应用包过滤技术，代理服务技术和其他一些技术的发展趋势。     

非晶硅太阳能电池的新进展

对非晶硅材料的物理性能及工艺优势进行了阐述，其中介绍了一种新型的刻划成图工艺，即等离子CVM，简单回顾了非晶硅太阳池的历史发展，分析了非晶硅太阳电池当前所存在的问题，提出了其发展的方向，其中，主要论述了叠层非晶硅太阳电池，并介绍了几种新型的非晶硅电池，最后，概括了非晶硅太阳电池的应用现状及前景。     

马

马，本来自由自在的在山间撒野，渴了喝点山泉，累了就睡在地上晒太阳，无忧无虑。可是自从有了伯乐，马的命运就改变了，给它的头戴上笼辔，在它的背上置放鞍具，栓着它，马的死亡率已经是十之二三了，然后再逼着它运输东西，强迫它日行千里，在它的脚上钉上铁掌，马的死亡率就过半了。     

手机充电器应该统一标准

在家里收拾屋子，手机的充电器竞有十多个，两个人用了七八年的手机，坏了、丢了、换了的手机也有七八个，一部手机还常有双充，可不就十多个充电器了。经常的情况是手机坏了，充电器却并不坏，买了新的手机，当然也配有新的充电器，旧的充电器扔了，是个浪费，不扔，能有什么用?我想这样的情况，其他手机用户也都一样，数数家里手机充电器，可能都不少。     

寻呼机制造技术最新进展

本文简述了无线寻呼机制造技术的最新发展，详细介绍了寻呼机在小型化，增加信息存储，提高抗干扰能力，增加新功能方面采用的新技术，新方法，强调了模糊技术，纠错技术对提高寻呼机抗干扰能力的作用，最后，展望了寻呼机制造技术的发展趋势。     

集邮队伍崛起一支生力军——重庆青少年集邮与教学活动走笔

重庆市“教学与集邮”活动已走过10年的历程。10年来，存重庆邮政、邮协及各级教委的支持下，重庆市各中小学对“教学与集邮”展开了广泛深入的研究，组织了集邮活动，举办了集邮讲座，推出了一批“教学与集邮”校本教材，取得了累累硕槊。集邮进校园、进课堂，使集邮活动在校园扎根，大大丰富了校园文化内容，引发了广大青少年对集邮这项健康、文明活动的兴趣，拓宽了学生的综合宴践能力，陶冶了学生的高尚情操，提高了学生思想素质和文化艺术素养，培育了集邮队伍的生力军。     

采用二值序列变换的形状匹配

本文对形状的模板匹配进行了研究，引入了形状的数学形态学二值序列变换，定义了形状匹配函数，讨论它的性质，建立了一个形状模板集合，提出了新的形状识别方案，它具有简单，高效，稳健和易于并行化处理的特点，最事，新的形状匹配算法被用于交通的标志中的识别，实验结果证实了新算法的稳健性和有效性。     

安徽电视台开放式演播室系统设计

介绍了安徽电视台开放式演播室的整体布局，逐一分析了电源，灯光，视频，音频，通话，指示，时钟和传输系统，其中重点介绍了视频和音频系统。     

冠图关爱手机——GPS服务的新亮点

星期五早上8点，老王刚到办公室不久就收到了一条短信，掏开手机一看，原来是读小学五年级的儿了已经到学校了，手机上关爱软件的电子地图准确地显示着儿子当前的位置；下午4点半，老王又收到一条短信，查看一下手机，哦，儿子已经离开学校了；过了40分钟，老王的手机又响了：“呵呵，儿子已经到家了，放心了，我现在可以安心地把要命的合同起草完成”。     

EPON 和 GPON 的 OAM 功能及其比较

着重介绍了目前被业界看好的两种无源光接入网EPON和GPON中的网络操作维护管理(OAM)的技术,包括OAM实现的功能、帧的结构及其特点.此外,还分析比较了EPON OAM和GPON OAM的异同点.     

TOPICS IN OPTICAL COMMUNICATIONS - STARGATE: The Next Evolutionary Step toward Unleashing the Potential of WDM EPONs

WDM EPONs are rapidly becoming mature. In this article we briefly review the state of the art of cost reduction, colorless ONUs, and WDM PONs. We then lift the veil of future WDM EPONs, and elaborate on evolutionary cost-effective upgrades of WDM EPONs and their all-optical WDM integration with Ethernet-based metropolitan area networks to provide transparent connections at the wavelength and sub-wavelength granularity on demand between ONUs residing in different WDM EPONs     

WDM Ethernet passive optical networks

WDM EPONs not only allow for cautious pay-as-you-grow upgrades of single-channel TDM EPONs but also avoid linearly increasing polling cycle times for an increasing number of ONUS. In this article, we first provide a comprehensive overview of the state of the art of TDM EPONs and recently reported dynamic bandwidth allocation algorithms, including decentralized scheduling schemes. After reviewing previous work on WDM EPONs, we address the requirements of WDM upgraded EPONs and make recommendations on an evolutionary WDM upgrade at the architecture, protocol, and dynamic bandwidth allocation algorithm levels, taking backward compatibility with MPCP and future-proofness against arbitrary WDM ONU structures into account. We describe and compare online and offline scheduling paradigms for WDM EPONs. Our simulation results indicate that online scheduling can achieve lower delays, especially at high loads. We outline areas of future research on WDM EPONs.     

A midterm DBA algorithm for quality of service on aggregation layer EPON networks

This work presents a new approach on dynamic bandwidth allocation (DBA) for Ethernet Passive Optical Networks (EPONs). A brief introduction to the DBA area and major term definitions are given. The related research and standardization efforts are presented. Justification that EPONs can be used on the aggregation network is provided, based on their evolution and related research proposals. Focus is given to the Long Reach-Passive Optical Networks (LR-PONs) and their limitations which show the need for a non-polling, midterm DBA scheme for next-generation EPONs. The challenges arising, because of this new approach, are discussed along with possible solutions. Finally, this work proposes the EMDBA algorithm which is able to overcome the discussed issues. The correct operation of this algorithm is confirmed by a set of simulations using OMNet++ framework, and the outcome results show that EMDBA performance is satisfactory in terms of delay and service differentiation.     

Per-Stream QoS and Admission Control in Ethernet Passive Optical Networks (EPONs)

Ethernet passive optical networks (EPONs) are designed to deliver services for numerous applications such as voice over Internet protocol, standard and high-definition video, video conferencing (interactive video), and data traffic. Various dynamic bandwidth allocation and intra-optical network unit (ONU) scheduling algorithms have been proposed to enable EPONs to deliver differentiated services for traffic with different quality of service (QoS) requirements. However, none of these protocols and schedulers can guarantee bandwidth for each class of service nor can they protect the QoS level required by admitted real-time traffic streams. In this paper, we propose the first framework for per-stream QoS protection in EPONs using a two-stage admission control (AC) system. The first stage enables the ONU to perform flow admission locally according to the bandwidth availability, and the second stage allows for global AC at the optical line terminal. Appropriate bandwidth allocation algorithms are presented as well. An event-driven simulation model is implemented to study the effectiveness of the proposed schemes in providing and protecting QoS.     

Enhanced Dynamic Bandwidth Allocation Algorithm in Ethernet Passive Optical Networks

As broadband access is evolving from digital subscriber lines to optical access networks, Ethernet passive optical networks (EPONs) are considered a promising solution for next generation broadband access. The point‐to‐multipoint topology of EPONs requires a time‐division multiple access MAC protocol for upstream transmission. In this paper, we propose a new enhanced dynamic bandwidth allocation algorithm with fairness called EFDBA for multiple services over EPONs. The proposed algorithm is composed of a fairness counter controller and a fairness system buffer in the optical line terminal. The EFDBA algorithm with fairness can provide increased capability and efficient resource allocation in an EPON system. In the proposed EFDBA algorithm, the optical line termination allocates bandwidth to the optical network units in proportion to the fairness weighting counter number associated with their class and queue length. The proposed algorithm provides efficient resource utilization by reducing the unused remaining bandwidth made by idle state optical network units.     

Bandwidth allocation for multiservice access on EPONs

Ethernet passive optical networks are a low-cost high-speed solution to the bottleneck problem of the broadband access network. A major characteristic of EPONs is the shared upstream channel among end users, mandating efficient medium access control to facilitate statistical multiplexing and provision multiple services for different types of traffic. This article addresses and provides an overview of the upstream bandwidth allocation issue for multiservice access provisioning over EPONs, and proposes an algorithm for dynamic bandwidth allocation with service differentiation. Based on the multipoint control protocol (MPCP) and bursty traffic prediction, our algorithm enhances QoS metrics such as average frame delay, average queue length, and frame loss probability over other existing protocols     

Adaptive polling algorithm to provide subscriber and service differentiation in a Long-Reach EPON

A novel interleaved polling algorithm for Long-Reach EPONs is proposed in order to simultaneously provide subscriber and class of service differentiation. It is demonstrated that the new polling algorithm applied to a typical 100 km Long-Reach EPON performs better than centralized methods, where bandwidth prediction is needed to overcome the higher round trip time in which ONUs cannot transmit. As polling methods in Long-Reach EPONs do not require prediction, they are much simpler and show less computational complexity than centralized schemes, avoiding the inaccuracy of bandwidth prediction. Simulation results show that the new algorithm increases the achieved throughput when compared to centralized algorithms with traffic prediction, obtaining a significant reduction of both mean packet delay and packet loss ratio for the highest priority service level profiles.     

Cyclic Polling-Based Dynamic Bandwidth Allocation for Differentiated Classes of Service in Ethernet Passive Optical Networks

Ethernet passive optical networks (EPONs) are an emerging access network technology that provides a low-cost method of deploying optical access lines between a carrier's central office and customer sites. Dynamic bandwidth allocation (DBA) provides statistical multiplexing between the optical network units for efficient upstream channel utilization. To support dynamic bandwidth distribution, a cyclic polling-based DBA algorithm for differentiated classes of service in EPONs is proposed. It is shown that an interleaved polling scheme severely decreases downstream channel capacity for user traffic when the upstream network load is low. To obtain realistic simulation results, synthetic traffic that exhibits the properties of self-similarity and long-range dependence is used. Network performance under various loads is analyzed. Specifically, frame delays for different classes of traffic are considered.     

A survey of dynamic bandwidth allocation algorithms for Ethernet Passive Optical Networks

Ethernet Passive Optical Network (EPON) has been widely considered as a promising technology for implementing the FTTx solutions to the “last mile” bandwidth bottleneck problem. Bandwidth allocation is one of the critical issues in the design of EPON systems. In an EPON system, multiple optical network units (ONUs) share a common upstream channel for data transmission. To efficiently utilize the limited bandwidth of the upstream channel, an EPON system must dynamically allocate the upstream bandwidth among multiple ONUs based on the instantaneous bandwidth demands and quality of service requirements of end users. This paper introduces the fundamental concepts on EPONs, discusses the major issues related to bandwidth allocation in EPON systems, and presents a survey of the state-of-the-art dynamic bandwidth allocation (DBA) algorithms for EPONs.