This paper presents a multi-interface embedded server architecture for remote real-time monitoring system and distributed monitoring applications. In the scheme,an embedded microprocessor( LPC3250 from NXP) is chosen ...This paper presents a multi-interface embedded server architecture for remote real-time monitoring system and distributed monitoring applications. In the scheme,an embedded microprocessor( LPC3250 from NXP) is chosen as the CPU of the embedded server with a linux operation system( OS) environment. The embedded server provides multiple interfaces for supporting various application scenarios. The whole network is based on local area network and adopts the Browser / Server( B / S) model. The monitoring and control node is as a browser endpoint and the remote node with an embedded server is as a server endpoint. Users can easily acquire various sensors information through writing Internet protocol address of remote node on the computer browser. Compared with client / server( C / S) mode,B / S model needs less maintain and can be applicable to large user group. In addition,a simple network management protocol( SNMP) is used for management of devices in Internet protocol( IP) networks. The results of the demonstration experiment show that the proposed system gives good support to manage the network from different user terminals and allows the users to better interact with the ambient environment.展开更多
In monitoring Wireless Sensor Networks(WSNs),the traffic usually has bursty characteristics when an event occurs.Transient congestion would increase delay and packet loss rate severely,which greatly reduces network pe...In monitoring Wireless Sensor Networks(WSNs),the traffic usually has bursty characteristics when an event occurs.Transient congestion would increase delay and packet loss rate severely,which greatly reduces network performance.To solve this problem,we propose a Burstiness-aware Congestion Control Protocol(BCCP) for wireless sensor networks.In BCCP,the backoff delay is adopted as a congestion indication.Normally,sensor nodes work on contention-based MAC protocol(such as CSMA/CA).However,when congestion occurs,localized TDMA instead of CSMA/CA is embedded into the nodes around the congestion area.Thus,the congestion nodes only deliver their data during their assigned slots to alleviate the contention-caused congestion.Finally,we implement BCCP in our sensor network testbed.The experiment results show that BCCP could detect area congestion in time,and improve the network performance significantly in terms of delay and packet loss rate.展开更多
为了从技术管理方面提高电力监控系统的安全性,避免发生无意与恶意破坏事件,面向电力监控系统的实时数据信息存储与处理,提出将用于过程控制的对象连接与嵌入(Object Linking and Embedding for Process Control,OPC)技术用于网络安全...为了从技术管理方面提高电力监控系统的安全性,避免发生无意与恶意破坏事件,面向电力监控系统的实时数据信息存储与处理,提出将用于过程控制的对象连接与嵌入(Object Linking and Embedding for Process Control,OPC)技术用于网络安全风险预警。概述设计所用的OPC服务器结构,设计基于OPC技术的电力监控系统,结合防火墙与入侵侦测技术,提高整个电力监控系统的安全管理水平,提取正常时隙预警信息为正常样本。结果发现,基于OPC技术的电力监控系统安全预警,在准确度方面具有优越性,证实了设计的基于OPC技术的电力监控系统在电力日常监管工作中的安全适用性。展开更多
基金Sponsored by the National High Technology Research and Development Program(Grant No.2012AA02A604)
文摘This paper presents a multi-interface embedded server architecture for remote real-time monitoring system and distributed monitoring applications. In the scheme,an embedded microprocessor( LPC3250 from NXP) is chosen as the CPU of the embedded server with a linux operation system( OS) environment. The embedded server provides multiple interfaces for supporting various application scenarios. The whole network is based on local area network and adopts the Browser / Server( B / S) model. The monitoring and control node is as a browser endpoint and the remote node with an embedded server is as a server endpoint. Users can easily acquire various sensors information through writing Internet protocol address of remote node on the computer browser. Compared with client / server( C / S) mode,B / S model needs less maintain and can be applicable to large user group. In addition,a simple network management protocol( SNMP) is used for management of devices in Internet protocol( IP) networks. The results of the demonstration experiment show that the proposed system gives good support to manage the network from different user terminals and allows the users to better interact with the ambient environment.
基金supported in part by National Key Basic Research Program of China(973 program)under Grant No.2007CB307101National Natural Science Foundation of China under Grant No.60833002,60802016,60972010
文摘In monitoring Wireless Sensor Networks(WSNs),the traffic usually has bursty characteristics when an event occurs.Transient congestion would increase delay and packet loss rate severely,which greatly reduces network performance.To solve this problem,we propose a Burstiness-aware Congestion Control Protocol(BCCP) for wireless sensor networks.In BCCP,the backoff delay is adopted as a congestion indication.Normally,sensor nodes work on contention-based MAC protocol(such as CSMA/CA).However,when congestion occurs,localized TDMA instead of CSMA/CA is embedded into the nodes around the congestion area.Thus,the congestion nodes only deliver their data during their assigned slots to alleviate the contention-caused congestion.Finally,we implement BCCP in our sensor network testbed.The experiment results show that BCCP could detect area congestion in time,and improve the network performance significantly in terms of delay and packet loss rate.
文摘为了从技术管理方面提高电力监控系统的安全性,避免发生无意与恶意破坏事件,面向电力监控系统的实时数据信息存储与处理,提出将用于过程控制的对象连接与嵌入(Object Linking and Embedding for Process Control,OPC)技术用于网络安全风险预警。概述设计所用的OPC服务器结构,设计基于OPC技术的电力监控系统,结合防火墙与入侵侦测技术,提高整个电力监控系统的安全管理水平,提取正常时隙预警信息为正常样本。结果发现,基于OPC技术的电力监控系统安全预警,在准确度方面具有优越性,证实了设计的基于OPC技术的电力监控系统在电力日常监管工作中的安全适用性。
