基于PPPoE的带宽汇聚NAT设计与实现

PPPoE技术使得已有的以太网能方便地实现宽带接入和计费功能,但Windows操作系统内置的PPPoE及ISP只支持用户单帐号登录,用户即使登录多个宽带帐号,再开启系统的宽带共享功能,也只能共享一个帐号的带宽。为解决这一问题,使用户能够在多帐号的状态下实现高速数据传输,在PPPoE的基础上,设计并实现了一个可以汇聚多个帐号带宽的NAT系统。实验结果表明,运行该系统时,用户登录帐号越多,链路带宽越大,实现了汇聚多帐号带宽的功能,为用户和ISP实现高速接入提供了另外一种途径。     

基于带宽聚合技术的3G视频传输系统设计

传统3G视频传输系统通过针对视频内容编码、打包以及传输控制等方面进行优化,来提高视频传输的质量,但是带宽不足的问题一直没有得到有效的解决.该文利用现有的策略路由、虚拟隧道和多网卡绑定三种成熟的网络技术,提出一种基于带宽聚合技术的3G视频传输系统设计方案,并给出其在TMS320DM3730开发板上的具体实现过程.实验结果表明,该系统能够有效聚合3G带宽、提高实时传输视频质量.     

Design and implementation of a Secure Bandwidth Broker Discovery Protocol

Differentiated Services architecture definition lacks control level functionalities. One of the solutions proposed to fill this gap is Bandwidth Brokers (BB). Bandwidth Brokers are autonomous entities inside a network which is responsible for bandwidth management of the network along with other tasks. There is a lack of protocol for Bandwidth Brokers to discover other Bandwidth Brokers automatically. This study introduces a new Secure Bandwidth Broker Discovery Protocol (BBDP), which allows Bandwidth Brokers to automatically discover other Bandwidth Brokers. In this paper design principles, protocol details, working scenarios and implementation details of the BBDP protocol are presented.     

网络拓扑自动发现系统的设计与实现

在对目前的网络拓扑自动发现技术深入分析研究的基础上,设计并实现了一个网络拓扑发现系统。该系统能够从多个数据源中获取网络拓扑信息,具有网络拓扑自动分级发现和网络拓扑自动分层表示的功能。较传统的网络拓扑发现系统而言,该系统具有设计复杂度低、发现的网络拓扑完整和直观的优点。     

智能家居虚拟场景设计与实现

面向智能家居应用,以Unity 3D为虚拟现实开发平台,给出了用虚拟智能化家庭场景实现虚拟场景家电设备及环境监测设备的模型设计。平台中的虚拟人可以在虚拟场景中自由漫游,并且通过虚拟人手中的终端设备,实时家电控制并获得环境监测设备的实时数据,使得家庭控制更加生动形象,实现虚拟与现实的融合。虚拟场景的设计有助于智能家居的宣传、培训和展示,同时让用户通过远程操作,也可以体验到真实的智能家居系统,零距离展示智能家居实验室的科研成果。     

Design,implementation, and evaluation of a single-copy protocol stack

Data copying and checksumming are the most expensive operations on hosts performing high-bandwidth network I/O over a high-speed network. Under some conditions, outboard buffering and checksumming can eliminate accesses to the data, thus making communication less expensive and faster. One of the scenarios in which outboard buffering and checksumming pays off is the common case of applications accessing the network using the Berkeley sockets interface and the Internet protocol stack. In this paper, we describe the host software for a host interface with outboard buffering and checksumming support. The platform used is DEC Alpha workstations with a Turbochannel I/O bus and running the DEC OSF/1 operating system. Our implementation does not only achieve ‘single copy’ communication for applications that use sockets, but it also interoperates efficiently with in-kernel applications and other network devices. Measurements show that for large reads and writes the single-copy path through the stack is five to seven times more efficient than the traditional implementation. We also present a detailed analysis of the measurements using a simple I/O model. © 1998 John Wiley & Sons, Ltd.     

Design,implementation and evaluation of a virtual storage system

Large organizations always have a strong demand for storage from data‐intensive applications and instruments. In this paper, we present the design, implementation, and evaluation of a new virtual storage system, Storage@desk, which can aggregate a large number of distributed machines within an organization to provide storage services with quality of service guarantees. Because storage virtualization is the prominent goal, Storage@desk provides clients with the abstraction of a hard drive by utilizing the Internet SCSI protocol. As such, data access to new storage services is transparent so that clients do not need to modify any existing applications nor change their current practices. Storage@desk replicates data and employs version‐based journaling for high availability. It utilizes a market‐based model for resource management and a feedback controller for automated performance control. We have developed a prototype of Storage@desk that implements the core components. Copyright © 2010 John Wiley & Sons, Ltd.     

Design,implementation and evaluation of a deadlock-free routing algorithm for concurrent computers

This paper describes the design, the implementation, and the performance results of a routing algorithm which provides deadlock-free communication in a tightly coupled message-passing concurrent computer. The algorithm is adaptive, isolated and uses the store-and-forward technique. It allows message communication between two processes regardless of where they are physically located on the network. The routing algorithm has many positive characteristics including provable deadlock freedom, guaranteed message arrival, and automatic local congestion reduction. It can be used as a basis for the design of high-level communication primitives. An Occam implementation on a network of inmos Transputers is discussed. The experimental results show that the routing algorithm is effective to support process to process communication on a concurrent computer.     

智能家居远程控制系统的设计与实现

物联技术的发展使智能家居成为改善人类生活质量的一个重要指标。文章实现了一个基于ARM的智能家居远程控制系统。该系统以S3C44B0X为核心处理器,外部扩展了Flash、SDRAM及网络接口;通过定制的湿度、风速传感器采集环境数据;用步进电机、继电器和被控对象相连接来控制其移动。在软件设计时移植了引导程序Bootloader及uClinux操作系统,并采用Boa和CGI的方式在uClinux上构建了Web服务器;完成了基于嵌入式Web服务器的网站程序,用来接收用户请求、返回页面及调用相关子程序(采集、控制),最终实现了智能家居远程网络控制的系统要求。     

个性化智能家庭供暖系统的设计与实现

分析了现有供暖系统的特点,结合智能家庭的发展趋势及个性化的应用需求提出了一种具有开放式、可扩展特点的新型智能型家庭供暖系统HeatingCare.进而重点研究了家庭暖气控制单元LHA中的供热控制模型及动态调节算法等核心技术.在分析、解决相关关键技术的基础上,最终在eBox与Windows CE构成的平台上成功实现了该嵌入式系统.     

一种智能家庭嵌入式系统的设计与实现*

针对电力线载波技术是实现家庭与个人信息化“最后10米”问题最有效手段之一,提出了一种基于电力线载波通信的家庭智能化解决方案;借助电力线的公共性,采用载波通信处理芯片,设计智能家庭嵌入式软件系统,实现对智能家庭管理的灵活性和便捷性。     

可编程OSD输出译码器片上系统结构的设计与实现

本文详细介绍了一种集成了标准8051MCU核和OSD输出控制逻辑的片上系统集成芯片。通过分析文字的点阵输出原理和行频、场频控制逻辑,实现了可编程的单片文本输出译码的片上系统设计,并对该系统的功能进行了仿真与验证。     

一种可编程链路测试系统的设计与实现

针对目前卫星地面站链路测试系统测试流程固化的问题,采用了虚拟机的思想,设计了一个执行测试指令的指令机,基于该指令机,实现了一种可编程的链路测试系统;该系统为不同的链路测试建立了一个统一的测试框架,简化了软件系统的结构;同时,该系统定义了自己的测试脚本格式,极大地增强了测试系统的可编程性和可扩展性;实际应用中编写了14种链路测试脚本,形成通用测试库,基于该库顺利完成了该站的链路指标测试工作,系统运行稳定,测试数据准确可靠;通过修改脚本,可以方便地设计新的测试流程,大大提高了测试的可扩充性和测试效率,具有一定的实用性和推广价值。     

Design,implementation, and evaluation of a low-complexity vector-core for executing scalar/vector instructions

This paper proposes a low-complexity vector-core called LcVc for executing both scalar and vector instructions on the same execution datapath. A unified register file in the decode stage is used for storing both scalar operands and vector elements. The execution stage accepts a new set of operands each cycle and produces a new result. Rather than issuing a vector instruction (1-D operations) as a whole, each vector operation is issued sequentially with the existing scalar issue hardware. In the first implementation of LcVc, all loads and stores of registers take place from the data cache in the memory access stage in a rate of one element per clock cycle. The complete design of our proposed LcVc processor is implemented using VHDL targeting the Xilinx FPGA Spartan 3E, xc3s1600e-4-fg320 device. The total number of slices required for implementing LcVc is 1778, where the number of slice flip-flops is 538 and the number of 4-input LUTs is 3706: 1914 for logic and 1792 for RAMs. Moreover, our performance evaluation results show that the speedup of executing vector addition, vector scaling, SAXPY, and matrix–matrix multiplication on LcVc over the scalar execution are 2.3, 2.5, 1.9, and 3, respectively. The hardware required to support the enhanced vector capability is insignificant (5%), which results in reducing the area per core and increasing the number of cores available in a given chip area.     

可编程电源系统的设计与实现

介绍了一种实用的可编程电源系统的设计与实现,该系统以C8051F020单片机为中央控制单元,以VICOR DC—DC系列电源模块为主供电单元,能够多通道、全隔离地输出多路稳定的电压,分别利用MAX186和MAX472对输出的电压值和电流值进行采样,并将采样结果实时地显示在屏幕上;设计了过（欠）压和过流自动保护的功能,同时可以通过计算机的串口对其进行遥控操作,实践表明。该电源系统电压调整范围可达50％～110％,调压误差〈1．5％,整个系统操作简单,运行稳定,具有较好的实用性和经济性。     

一种汽车底盘自动润滑系统程控器的设计

文章介绍了一种以AVR单片机为核心设计的汽车底盘自动润滑系统中的程序控制器。简要介绍了程控器在汽车自动润滑系统中的作用;阐述了程控器的工作原理;从单片机的选择、点火开关、系统压力等信号的检测电路及键盘与显示电路等部分进行了硬件电路设计,并根据系统的工作过程给出了软件的处理流程框图。该程控器体积小、功能强、成本低。经实际检验,能满足系统要求,具有良好的社会效益和经济效益。     

无线传感器网络CMR路由协议的设计与实现

在基于簇的路由算法基础上,结合多跳路由的设计思想,提出了一种基于簇的多跳路由协议（CMR）,着重对路由协议的设计思想,簇组织算法和簇间路由算法的工作过程进行了分析和论述,包括簇首选举与簇建立、簇重组与自愈机制,以及簇间路由建立与维护等,并给出了协议的实现,最后对协议进行了测试。     

Design, implementation, and evaluation of differentiated caching services

With the dramatic explosion of online information, the Internet is undergoing a transition from a data communication infrastructure to a global information utility. PDAs, wireless phones, Web-enabled vehicles, modem PCs, and high-end workstations can be viewed as appliances that "plug-in" to this utility for information. The increasing diversity of such appliances calls for an architecture for performance differentiation of information access. The key performance accelerator on the Internet is the caching and content distribution infrastructure. While many research efforts addressed performance differentiation in the network and on Web servers, providing multiple levels of service in the caching system has received much less attention. It has two main contributions. First, we describe, implement, and evaluate an architecture for differentiated content caching services as a key element of the Internet content distribution architecture. Second, we describe a control-theoretical approach that lays well-understood theoretical foundations for resource management to achieve performance differentiation in proxy caches. An experimental study using the Squid proxy cache shows that differentiated caching services provide significantly better performance to the premium content classes.     

无线传感器网络中移动节点设备的设计和实现

提出了一款机器人的设计方案,将机器人作为移动的传感器节点,汇集静态传感器节点的数据,感知周边物理环境的信息。机器人主要由微处理器模块、通信单元模块和用于移动的底座平台组成,微处理器嵌入源码开放的事件驱动操作系统!C/OS-II。由机器人和静态传感器节点组建的网络实验结果显示,机器人运行稳定,能可靠提高网络通信能力。