基于IEEE1451标准的智能变送器接口电路

针对传统传感器只能应用在某种特定网络的问题，采用IEEE1451标准的智能变送器接口模型进行电路的软硬件设计．将传统传感器划分为智能变送器接口模块(STIM)与网络适配器(NCAP)．在智能变送器接口模块中使用8051单片机对变送器传来的信号进行调理、转换和线性化，实现与网络适配器的通信；在网络适配器中使用ARM处理器对智能变送器接口模块进行控制并对传来数据进行处理，且与各种工业网络进行通信．     

基于IEEE 1451．2的输油管道泄漏无线监测系统研究

基于IEEE 1451．2标准和无线网络测量技术,设计了一种输油管道泄漏监测系统。IEEE 1451．2标准描述了电子数据表格TEDS及其数据格式,规定了一个连接网络适配处理器NCAP到智能传感器接口模块STIM的数字接口TII。详细介绍了监测系统的实现方法,重点讨论无线网络模块的应用与通信方法的实现。通过测试,系统工作正常,显示结果达到输油管道的测量要求。     

基于IEEE1451标准的电机智能监测系统研究

针对大型电机综合监测系统传感器接口兼容及网络互操作性问题,基于IEEE1451标准接口,对开放式、"即插即用"的智能监测系统做集成研究;基于IEEE1451标准,完成网络节点执行器模块(STIM)、TII接口电路及传感器电子数据表单(TEDS)方案的设计;基于CAN总线技术完成网络适配器(NCAP)硬件模块和通讯协议的开发,编制了节点通信优先晋升协议;实验分析表明,系统可靠性高,实时性良好。     

大型电机转子表面温度的网络系统测量

针对大型电机转子表面温度的非接触光纤测温方法和网络化传感器的基本特点,研究了大型电机转子表面温度的网络系统测量;提出了采用CAN总线作为TII接口协议完成STIM和NCAP的长距离连接方法,实现了大型电机转子表面温度的远程在线监测与控制,其测量精度达到0.2%。     

网络传感器接口设计与验证

以ADuC812微控制器为核心,依据网络智能传感器接口标准IEEE 1451.2,探索了智能传感器接口模块(STIM)的设计思想与实现方法,用PC机编制程序实现网络匹配处理器(NCAP)的功能,在线存储、修改电子数据表单(TEDS),实现传感器/执行器的即插即用。     

基于IEEE1451的大型环保设备智能传感系统研究

结合智能传感器技术和智能传感系统的发展方向,针对目前大型环保设备状态监测与传感系统中存在的各种问题,利用IEEE1451标准,研究智能传感系统技术在大型环保设备状态监测中的应用,完成了系统智能前端,包括混合传感器接口、智能传感器模块、网络接口模块及TEDS方案的设计与实现,研制了一种适合于大型环保设备状态监测的网络化智...     

A VHDL-based protocol controller for NCAP processors

This work presents the development of an IEEE 1451.2 protocol controller based on a low-cost FPGA that is directly connected to the parallel port of a conventional personal computer. In this manner it is possible to implement a Network Capable Application Processor (NCAP) based on a personal computer, without parallel port modifications. This approach allows supporting the ten signal lines of the 10-wire IEEE 1451.2 Transducer Independent Interface (TII), that connects the network processor to the Smart Transducer Interface Module (STIM) also defined in the IEEE 1451.2 standard. The protocol controller is connected to the STIM through the TII's physical interface, enabling the portability of the application at the transducer and network processor level. The protocol controller architecture was fully developed in VHDL language and we have projected a special prototype configured in a general-purpose programmable logic device. We have implemented two versions of the protocol controller, which is based on IEEE 1451 standard, and we have obtained results using simulation and experimental tests.     

基于IEEE145112 即插即用网络化传感器的研制

在介绍IEEE1451．2的基础上，结合STIM的构造思想，提出了一种即插即用网络化传感器的设计，详细介绍其设计思想，硬件结构，软件设计，结合出了传感器网络拓扑结构以及相应的网络接口设计，并介绍了它在机器人实验平台中的应用。     

Leveraging bandwidth improvements to web servers through enhanced network interfaces

Markets nowadays demand applications that require high communication throughputs to reach their adequate levels of performance. Although the bandwidth of the network links has increased allowing multiple gigabits per second, taking advantage of these links accounts for a high communication overhead, and thus a lot of processor cycles are used for communication tasks, diminishing the processor cycles that remain available for the application. In this paper, we evaluate the performance in web applications of a network interface that as it is distributed among the processors currently available in the node takes advantage of both the hardware (multiprocessor nodes and multicore architectures, as well as programmable network interface cards) and software elements present in the system, thus improving not only the effective communication throughputs and latencies, but also the capacity of the nodes to satisfy the requirements of the applications. Here, the usefulness of this distributed network interface to improve the performance of either static or dynamic web servers is shown. The ubiquity and the different computation/communication rates that can be found in web applications make the analysis of web servers interesting, as it could provide relevant conclusions about the efficiency of the different approaches to the design of high-performance network interfaces.     

反射内存高速光电转换接口单元设计与实现

针对远程分布式仿真测试系统的实际需求，提出了远距离多功能节点的设计方案，构建实现了以高速SFP光纤通信和反射内存网络为核心技术的高速光电转换接口单元；接口单元包括光纤转换器和多功能接口模块两个组成部分；其中多功能接口模块以 FPGA 为控制核心，借鉴PMC以及XMC结构，采用通用式母板与多种专用子板组合的硬件架构形式，实现了数字IO、LVDS、RS422、ARINC429、模拟量等多种通用接口，提高了硬件资源的复用性；母板与子板间通信选用GTX作为物理层，并设计了专用的通信协议帧格式，通过Verilog编程实现了协议的解析与通信控制，既实现了多种电信号接口的集成，又具有低数据处理延时的突出特点；实验测试表明，模块的数据处理延时可控制在800ns-1000ns，满足了分布式仿真节点间数据交互时对传输距离和实时性的要求。     

A user-centric and context-aware solution to interface management and access network selection in heterogeneous wireless environments

This paper investigates issues related to handover management of mobile terminals in heterogeneous wireless environments. The mobile terminals are equipped with multiple wireless radio interfaces and have a limited lifetime battery. Seamless mobility and power utilization efficiency become two important aspects of the handover management. We propose in this work user-centric network selection, power-saving interface management and adaptive handover initiation solutions at the terminal side to support seamless terminal-initiated and terminal-controlled vertical handover. The proposed access network selection is situation-aware and application-aware to suit different communication contexts. It enables terminals to select the most suitable access network according to various access network characteristics. Multiple wireless interfaces of a terminal device are handled in both idle and active communication modes to optimize the power consumption. We also address an adaptive handover initiation scheme to assist the service continuity. We conduct simulations and analyses of the proposed solutions to show their suitability and their efficiency.     

应用于计算机网络协议一致性测试的传输机制

测试传输在很大程度上影响测试系统实现和测试集设计．良好的传输方法能够对测试集设计者屏蔽被测协议实现的相关信息,同时简化测试配置．根据测试集设计和测试传输分离的思想,采用通信实体和网络接口相结合的机制实现测试传输,网络接口用于定义逻辑测试接口的类型和相应的参数,相当于一台逻辑测试器;通信实体用于向逻辑测试器屏蔽下层服务提供者的类型,完成测试数据的发送／接收工作．该传输机制在IPV6协议一致性测试系统中获得了成功。     

基于分布式对象的统一RTI接口设计与实现

统一的RTI接口是为了解决异构联邦成员的互操作问题而提出的,其设计目标是具有广泛的兼容性和可扩展性。该文介绍了分布式对象中间件及其接口定义语言,建立了RTI的分布式对象模型和接口抽象,探讨了统一RTI接口在集成不同语言和不同协议的联邦成员中的应用以及在层次式RTI中的扩展。     

Cooperative device discovery for multi-interface self-organizing networks

For device-to-device communications, a device must locate neighbor devices on a certain channel within a short period to establish a communication link. When the channel information is not provided, a rendezvous technique can be adapted to resolve the issue of device discovery. Unlike existing approaches that have considered the rendezvous problem for a flat network and a single interface, the proposed approach considers a hierarchical network where nodes have different ranks and multiple interfaces. We extend the jump-and-stay rendezvous algorithm for multiple interfaces and divide the interfaces into two types: standby and scan interfaces. Scan interfaces follow the extended pattern of the jump-and-stay algorithm. Standby interfaces remain on a selected channel for a round of slots until rendezvous with other nodes. To determine the interface type of each node, we consider the rank of a node such that a higher-ranked node is assigned more standby interfaces. Based on this framework, we propose a cooperative rendezvous algorithm where a node rebroadcasts the channel information of a higher-ranked node together with its rendezvous message. Our simulation results confirm that the proposed rendezvous algorithm achieves superior performance compared to conventional methods.     

Network interfaces for programmable NICs and multicore platforms

The availability of multicore processors and programmable NICs, such as TOEs (TCP/IP Offloading Engines), provides new opportunities for designing efficient network interfaces to cope with the gap between the improvement rates of link bandwidths and microprocessor performance. This gap poses important challenges related with the high computational requirements associated to the traffic volumes and wider functionality that the network interface has to support. This way, taking into account the rate of link bandwidth improvement and the ever changing and increasing application demands, efficient network interface architectures require scalability and flexibility. An opportunity to reach these goals comes from the exploitation of the parallelism in the communication path by distributing the protocol processing work across processors which are available in the computer, i.e. multicore microprocessors and programmable NICs.Thus, after a brief review of the different solutions that have been previously proposed for speeding up network interfaces, this paper analyzes the onloading and offloading alternatives. Both strategies try to release host CPU cycles by taking advantage of the communication workload execution in other processors present in the node. Nevertheless, whereas onloading uses another general-purpose processor, either included in a chip multiprocessor (CMP) or in a symmetric multiprocessor (SMP), offloading takes advantage of processors in programmable network interface cards (NICs). From our experiments, implemented by using a full-system simulator, we provide a fair and more complete comparison between onloading and offloading. Thus, it is shown that the relative improvement on peak throughput offered by offloading and onloading depends on the rate of application workload to communication overhead, the message sizes, and on the characteristics of the system architecture, more specifically the bandwidth of the buses and the way the NIC is connected to the system processor and memory. In our implementations, offloading provides lower latencies than onloading, although the CPU utilization and interrupts are lower for onloading. Taking into account the conclusions of our experimental results, we propose a hybrid network interface that can take advantage of both, programmable NICs and multicore processors.     

基于IEEE1451.2的智能变送器接口模块的设计与实现

IEEE1451.2标准为将不同的智能变送器连接到网络适配器(NCAP)或微处理器制定了一个统一的数字接口,真正实现了现场设备的即插即用。简述了IEEE1451.2标准,重点介绍了智能变送器接口模块(STIM)的软硬件设计思想和测试平台,通过实践验证了采用ADuC812芯片实现智能变送器接口模块的可行性。     

Virtual network transport protocols for Myrinet

Bringing direct and protected network multiprogramming into mainstream cluster computing requires innovations in three key areas: application programming interfaces, network virtualization systems, and lightweight communication protocols for high-speed interconnects. The AM-II API extends traditional active messages with support for client-server computing and facilitates the construction of parallel clients and distributed servers. Our virtual network segment driver enables a large number of arbitrary sequential and parallel applications to access network interface resources directly in a concurrent but fully protected manner. The NIC-to-NIC communication protocols provide reliable and at-most-once message delivery between communication endpoints. The NIC-to-NIC protocols perform well as the number of endpoints and the number of hosts in the cluster are scaled. The flexibility afforded by the underlying protocols enables a diverse set of timely research efforts. Other Berkeley researchers are actively using this system to investigate implicit techniques for the coscheduling of communicating processes, an essential part of high-performance communications in multiprogrammed clusters of uni- and multiprocessor servers. Other researchers are extending the active message protocols described here for clusters of symmetric multiprocessors, using so-called multiprotocol techniques and multiple network interfaces per machine     

一个基于CORBA的图形用户界面体系结构及实例

随着网络计算技术的发展,软件的结构变为表示／处理／数据库分离的三级模式。表示与处理的分离导致了用户界面与应用计算间的通信成为开发交互式系统图形用户界面的关键。本文为分布式交互图形应用的开发提供了一个基于公用对象需求代理结构ＣＯＲＢＡ的用户界面体系结构,ＣＯＲＢＡ是为分布式对象系统中间件制定的一个互操作标准。在这个结构中,一些被称为代理的面向对象交互式图形构件被设计用来为图形的表示与交互提供有效的解     

A systematic approach to host interface design for high-speednetworks

Optical fiber has made it possible to build networks with link speeds of over a gigabit per second; however, these networks are pushing end-systems to their limits. For high-speed networks (100 Mbits per second and up), network throughput is typically limited by software overhead on the sending and receiving hosts. Minimizing this overhead improves application-level latency and throughput and reduces the number of cycles that applications lose to communication overhead. Several factors influence communication overhead: communication protocols, the application programming interface (API). and the network interface hardware architecture. The author describes how these factors influence communication performance and under what conditions hardware support on the network adapter can reduce overhead. He first describes the organization of a typical network interface and discusses performance considerations for interfaces to high-speed networks. He then discusses software optimizations that apply to simple network adapters and show how more powerful adapters can improve performance on high-speed networks