Accurate time synchronization is fundamental to the correct and efficient operation of Wireless Sensor Networks(WSNs),especially in security-critical,time-sensitive applications.However,most existing protocols degrade...Accurate time synchronization is fundamental to the correct and efficient operation of Wireless Sensor Networks(WSNs),especially in security-critical,time-sensitive applications.However,most existing protocols degrade substantially under malicious interference.We introduce iSTSP,an Intelligent and Secure Time Synchronization Protocol that implements a four-stage defense pipeline to ensure robust,precise synchronization even in hostile environments:(1)trust preprocessing that filters node participation using behavioral trust scoring;(2)anomaly isolation employing a lightweight autoencoder to detect and excise malicious nodes in real time;(3)reliability-weighted consensus that prioritizes high-trust nodes during time aggregation;and(4)convergence-optimized synchronization that dynamically adjusts parameters using theoretical stability bounds.We provide rigorous convergence analysis including a closed-form expression for convergence time,and validate the protocol through both simulations and realworld experiments on a controlled 16-node testbed.Under Sybil attacks with five malicious nodes within this testbed,iSTSP maintains synchronization error increases under 12%and achieves a rapid convergence.Compared to state-ofthe-art protocols like TPSN,SE-FTSP,and MMAR-CTS,iSTSP offers 60%faster detection,broader threat coverage,and more than 7 times lower synchronization error,with a modest 9.3%energy overhead over 8 h.We argue this is an acceptable trade-off for mission-critical deployments requiring guaranteed security.These findings demonstrate iSTSP’s potential as a reliable solution for secure WSN synchronization and motivate future work on large-scale IoT deployments and integration with energy-efficient communication protocols.展开更多
This paper presents a novel real-time routing protocol, called CBRR, with less energy consumption for wireless sensor networks (WSNs). End-to-End real-time requirements are fulfilled with speed or delay constraint at ...This paper presents a novel real-time routing protocol, called CBRR, with less energy consumption for wireless sensor networks (WSNs). End-to-End real-time requirements are fulfilled with speed or delay constraint at each hop through integrating the contention and neighbor table mechanisms. More precisely, CBRR maintains a neighbor table via the contention mechanism being dependent on wireless broadcast instead of beacons. Comprehensive simulations show that CBRR can not only achieve higher performance in static networks, but also work well for dynamic networks.展开更多
The data acquisition stations and the data processing center of the Science and Application Center for Lunar and Deep-space Exploration (SACLuDE) are located at different geographical sites. They respectively have the...The data acquisition stations and the data processing center of the Science and Application Center for Lunar and Deep-space Exploration (SACLuDE) are located at different geographical sites. They respectively have their own local networks and interconnect with each other through access to the core data network. This paper describes the clock drift in the computer and other networked devices building up the infrastructure of the above local networks. The network time variance of the stochastic model is also estimated. The poor precision of network synchronization will bring about potential hazards to the network operation and application running in the networks, which is clarified in the present paper. At the end of the paper, a cost-effective and feasible solution is proposed based on the Global Position System (GPS) and the Network Time Protocol (NTP).展开更多
The authors propose a new persistent transmission based real time Ethernet MAC protocol that provides a predictable upper bound for the delivery delay of real time frames. Moreover, it is compatible with the protocol ...The authors propose a new persistent transmission based real time Ethernet MAC protocol that provides a predictable upper bound for the delivery delay of real time frames. Moreover, it is compatible with the protocol used by the existing Ethernet controllers for conventional datagram traffic and thus standard Ethernet stations can be used in the system without any modification. The paper describes the protocol in detail and analyses the maximum delivery delay for real time traffic and the efficiency of the channel.展开更多
Coverage holes often appear in wireless sensor networks due to sensor failure or the inheritance of sensor＇s random distribution. In the hybrid model, mobile sensors in the network are acquired to heal coverage holes...Coverage holes often appear in wireless sensor networks due to sensor failure or the inheritance of sensor＇s random distribution. In the hybrid model, mobile sensors in the network are acquired to heal coverage holes by their mobifity. When multiple coverage holes appear in the sensor network and each of them has a time requirement （in which the coverage hole has to be healed）, conflicts for the requests of the same mobile sensor may arise. A distributed multiple mobile sensor schedufing protocol （DMS） is proposed in this paper to solve this problem by finding mobile sensors in the time response zone defined by the time requirement of each coverage hole. Simulation results show that DMS can well schedule the mobile sensors to move to multiple coverage holes within the time requirement.展开更多
A reasonable parameter configuration helps improve the data transmission performance of the Licklider Transmission Protocol(LTP).Previous research has focused mainly on parameter optimization for LTP in simplified sce...A reasonable parameter configuration helps improve the data transmission performance of the Licklider Transmission Protocol(LTP).Previous research has focused mainly on parameter optimization for LTP in simplified scenarios with one to two hops or multihop scenarios with a custody mechanism of the Bundle Protocol(BP).However,the research results are not applicable to communications in Complex Deep Space Networks(CDSNs)without the custody mechanism of BP that are more suitable for deep space communications with LTP.In this paper,we propose a model of file delivery time for LTP in CDSNs.Based on the model,we propose a Parameter Optimization Design Algorithm for LTP(LTP-PODA)of configuring reasonable parameters for LTP.The results show that the accuracy of the proposed model is at least 6.47%higher than that of the previously established models based on simple scenarios,and the proposed model is more suitable for CDSNs.Moreover,the LTP parameters are optimized by the LTP-PODA algorithm to obtain an optimization plan.Configuring the optimization plan for LTP improves the protocol transmission performance by at least 18.77%compared with configuring the other parameter configuration plans.展开更多
Nodes in the communication network mainly depend on the Media Access Control(MAC)layer protocol design.To ensure the MAC protocol achieves high throughput,low latency,and high service quality,this paper designed a“ce...Nodes in the communication network mainly depend on the Media Access Control(MAC)layer protocol design.To ensure the MAC protocol achieves high throughput,low latency,and high service quality,this paper designed a“centralized-distribution”system MAC protocol combined with a slot allocation algorithm.This allows it to quickly adapt to the topology changes in the network and the overall network frame structure.For the centralized time slot allocation,since the system’s frame structure changes across the entire network,the root node must gather information from other nodes.This ensures that the root node can collect the latest topology information when the network topology changes and subsequently adjust the frame structure of the whole network for the distributed time slot allocation.The simulation results show that the adaptive time-division multiple access mechanism can quickly adapt to changes in topology and the network’s frame structure.It enables adaptive changes in node transmission times,ensures the rapid transmission and circulation of large-capacity data between nodes,and improves transmission efficiency.展开更多
目的 :解决应用服务器出现时间偏差会导致住院患者每日汇总报表数据不一致、护士看不到医生医嘱及患者的次日用药无法领取等隐患问题。方法:通过深入分析和大量模拟实验,提出一种基于网络时间协议(network time protocol,NTP)的时间同...目的 :解决应用服务器出现时间偏差会导致住院患者每日汇总报表数据不一致、护士看不到医生医嘱及患者的次日用药无法领取等隐患问题。方法:通过深入分析和大量模拟实验,提出一种基于网络时间协议(network time protocol,NTP)的时间同步改进技术,即定时更新NTP服务器硬件时间,以防止NTP服务器因故存在的硬件时钟累积误差问题;同时,采用自动校正NTP服务器冷启动后的系统时间,避免线上的客户机与不正确的时间进行同步。结果:在时间同步微调模式下,采用脚本后的改进技术大大缩短了时间同步。观察10 s的偏差同步时间可节省7 h以上,若时间更长(<600 s),则节省时间更多。结论:缩短了在线设备与NTP服务器的同步时间,解决了极端情况下的时间偏差问题。展开更多
Network Time Protocol(NTP)是用来使计算机及网络设备时间同步化的一种协议,其目的是为各种网络设备提供高精准度的时间校正。伴随着高校网络设备数量爆炸式增长,我们所依赖的文件服务器、邮件服务器、互联网网关等诸多网络设备之间都...Network Time Protocol(NTP)是用来使计算机及网络设备时间同步化的一种协议,其目的是为各种网络设备提供高精准度的时间校正。伴随着高校网络设备数量爆炸式增长,我们所依赖的文件服务器、邮件服务器、互联网网关等诸多网络设备之间都需要一个精准的时钟作为信息共享的基础,因为数据共享、设备日志和网络安全是互联网上最常用也是最易遭受攻击的信息。为确保网络设备安全,网络工程师需要精准的时间确保这些应用及其它关键网络应用的安全。本文基于NTP协议网络应用时间戳同步机制的研究,可有效应用于高校网络中,使所有网络设备的时间戳具有高度统一性。所以在互联网中设计专门的时间服务器为需要精准时间的网络设备同步成为当今日益复杂网络应用环境的现实需求。展开更多
基金this project under Geran Putra Inisiatif(GPI)with reference of GP-GPI/2023/976210。
文摘Accurate time synchronization is fundamental to the correct and efficient operation of Wireless Sensor Networks(WSNs),especially in security-critical,time-sensitive applications.However,most existing protocols degrade substantially under malicious interference.We introduce iSTSP,an Intelligent and Secure Time Synchronization Protocol that implements a four-stage defense pipeline to ensure robust,precise synchronization even in hostile environments:(1)trust preprocessing that filters node participation using behavioral trust scoring;(2)anomaly isolation employing a lightweight autoencoder to detect and excise malicious nodes in real time;(3)reliability-weighted consensus that prioritizes high-trust nodes during time aggregation;and(4)convergence-optimized synchronization that dynamically adjusts parameters using theoretical stability bounds.We provide rigorous convergence analysis including a closed-form expression for convergence time,and validate the protocol through both simulations and realworld experiments on a controlled 16-node testbed.Under Sybil attacks with five malicious nodes within this testbed,iSTSP maintains synchronization error increases under 12%and achieves a rapid convergence.Compared to state-ofthe-art protocols like TPSN,SE-FTSP,and MMAR-CTS,iSTSP offers 60%faster detection,broader threat coverage,and more than 7 times lower synchronization error,with a modest 9.3%energy overhead over 8 h.We argue this is an acceptable trade-off for mission-critical deployments requiring guaranteed security.These findings demonstrate iSTSP’s potential as a reliable solution for secure WSN synchronization and motivate future work on large-scale IoT deployments and integration with energy-efficient communication protocols.
文摘This paper presents a novel real-time routing protocol, called CBRR, with less energy consumption for wireless sensor networks (WSNs). End-to-End real-time requirements are fulfilled with speed or delay constraint at each hop through integrating the contention and neighbor table mechanisms. More precisely, CBRR maintains a neighbor table via the contention mechanism being dependent on wireless broadcast instead of beacons. Comprehensive simulations show that CBRR can not only achieve higher performance in static networks, but also work well for dynamic networks.
文摘The data acquisition stations and the data processing center of the Science and Application Center for Lunar and Deep-space Exploration (SACLuDE) are located at different geographical sites. They respectively have their own local networks and interconnect with each other through access to the core data network. This paper describes the clock drift in the computer and other networked devices building up the infrastructure of the above local networks. The network time variance of the stochastic model is also estimated. The poor precision of network synchronization will bring about potential hazards to the network operation and application running in the networks, which is clarified in the present paper. At the end of the paper, a cost-effective and feasible solution is proposed based on the Global Position System (GPS) and the Network Time Protocol (NTP).
基金TheNationalNaturalScienceFoundationofChina (No .6 9984 0 0 3)
文摘The authors propose a new persistent transmission based real time Ethernet MAC protocol that provides a predictable upper bound for the delivery delay of real time frames. Moreover, it is compatible with the protocol used by the existing Ethernet controllers for conventional datagram traffic and thus standard Ethernet stations can be used in the system without any modification. The paper describes the protocol in detail and analyses the maximum delivery delay for real time traffic and the efficiency of the channel.
基金supported by the National Natural Science Foundation of China under Grant No. 61133016
文摘Coverage holes often appear in wireless sensor networks due to sensor failure or the inheritance of sensor＇s random distribution. In the hybrid model, mobile sensors in the network are acquired to heal coverage holes by their mobifity. When multiple coverage holes appear in the sensor network and each of them has a time requirement （in which the coverage hole has to be healed）, conflicts for the requests of the same mobile sensor may arise. A distributed multiple mobile sensor schedufing protocol （DMS） is proposed in this paper to solve this problem by finding mobile sensors in the time response zone defined by the time requirement of each coverage hole. Simulation results show that DMS can well schedule the mobile sensors to move to multiple coverage holes within the time requirement.
基金supported by the Strategic Leading Project of the Chinese Academy of Sciences(No.XDA15014603).
文摘A reasonable parameter configuration helps improve the data transmission performance of the Licklider Transmission Protocol(LTP).Previous research has focused mainly on parameter optimization for LTP in simplified scenarios with one to two hops or multihop scenarios with a custody mechanism of the Bundle Protocol(BP).However,the research results are not applicable to communications in Complex Deep Space Networks(CDSNs)without the custody mechanism of BP that are more suitable for deep space communications with LTP.In this paper,we propose a model of file delivery time for LTP in CDSNs.Based on the model,we propose a Parameter Optimization Design Algorithm for LTP(LTP-PODA)of configuring reasonable parameters for LTP.The results show that the accuracy of the proposed model is at least 6.47%higher than that of the previously established models based on simple scenarios,and the proposed model is more suitable for CDSNs.Moreover,the LTP parameters are optimized by the LTP-PODA algorithm to obtain an optimization plan.Configuring the optimization plan for LTP improves the protocol transmission performance by at least 18.77%compared with configuring the other parameter configuration plans.
文摘Nodes in the communication network mainly depend on the Media Access Control(MAC)layer protocol design.To ensure the MAC protocol achieves high throughput,low latency,and high service quality,this paper designed a“centralized-distribution”system MAC protocol combined with a slot allocation algorithm.This allows it to quickly adapt to the topology changes in the network and the overall network frame structure.For the centralized time slot allocation,since the system’s frame structure changes across the entire network,the root node must gather information from other nodes.This ensures that the root node can collect the latest topology information when the network topology changes and subsequently adjust the frame structure of the whole network for the distributed time slot allocation.The simulation results show that the adaptive time-division multiple access mechanism can quickly adapt to changes in topology and the network’s frame structure.It enables adaptive changes in node transmission times,ensures the rapid transmission and circulation of large-capacity data between nodes,and improves transmission efficiency.
基金supported in part by the school scientific research project of Beijing University of Civil Engineering and Architecture,(101203308)
文摘Network Time Protocol(NTP)是用来使计算机及网络设备时间同步化的一种协议,其目的是为各种网络设备提供高精准度的时间校正。伴随着高校网络设备数量爆炸式增长,我们所依赖的文件服务器、邮件服务器、互联网网关等诸多网络设备之间都需要一个精准的时钟作为信息共享的基础,因为数据共享、设备日志和网络安全是互联网上最常用也是最易遭受攻击的信息。为确保网络设备安全,网络工程师需要精准的时间确保这些应用及其它关键网络应用的安全。本文基于NTP协议网络应用时间戳同步机制的研究,可有效应用于高校网络中,使所有网络设备的时间戳具有高度统一性。所以在互联网中设计专门的时间服务器为需要精准时间的网络设备同步成为当今日益复杂网络应用环境的现实需求。
