An explicit congestion notification (ECN)-based distributed transport protocol,ARROW-WTCP (AcceleRate tRansmission towards Optimal Window size TCP for Wireless network),was proposed.The ARROW-WTCP enables feasible dep...An explicit congestion notification (ECN)-based distributed transport protocol,ARROW-WTCP (AcceleRate tRansmission towards Optimal Window size TCP for Wireless network),was proposed.The ARROW-WTCP enables feasible deployment of ARROW-TCP from wired to wireless networks by providing a joint design of source and router algorithms.The protocol obtains the actual capacity of the wireless channel by calculating the queue variation in base station (BS) and adjusts the congestion window by using the feedback from its bottleneck link.The simulation results show that the ARROW-WTCP achieves strong stability,max-min fairness in dynamic networks,fast convergence to efficiency without introducing much excess traffic,and almost full link utilization in the steady state.It outperforms the XCP-B (eXplicit Control Protocol Blind),the wireless version of XCP,in terms of stability,fairness,convergence and utilization in wireless networks.展开更多
This paper proposed a practical- feedback scheme for fountain codes based transportprotocol in space communications. In the proposed scheme, the sender is signaled by two types of acknowledgment （ACK） packets.Before...This paper proposed a practical- feedback scheme for fountain codes based transportprotocol in space communications. In the proposed scheme, the sender is signaled by two types of acknowledgment （ACK） packets.Before decoding, packet loss probability isestimated on the receiver side and encapsulated intoa soft ACKand sent to the sender.After decoding,decoding results are encapsulated into hard ACKsandsent to the sender. There are two contributionsin the proposed scheme： 1. Empl layer calculation instead layer statistics to estimate oying physical of application the packet loss probability of space channel, which can improvethe accuracy and practicality. 2. A cascade overhead-failure probability relationship between the sender and the receiver has been analyzed to help determine the exact numberof packetsneeded byfountain decoding.Simulations show that for space communications,compared with the existing space transport protocols, fountain codes based transport protoeolwith the proposed schemecan not only ensure transmission reliability, but also greatly improvelink utilization.展开更多
As a result of the exponential growing rate of worldwide Internet usage, satellite systems are required to support broadband Internet applications. The transmission control protocol （TCP） which is widely used in the...As a result of the exponential growing rate of worldwide Internet usage, satellite systems are required to support broadband Internet applications. The transmission control protocol （TCP） which is widely used in the Internet, performs very well on wired networks. However, in the case of satellite channels, clue to the delay and transmission errors, TCP performance degrades significantly and bandwidth of satellite links can not be fully utilized. To improve the TCP performance, a new idea of placing a TCP spoofing proxy in the satellite is considered. A Novel Satellite Transport Protocol （NSTP） which takes advantage of the special properties of the satellite channel is also proposed. By using simulation, as compared with traditional TCPs, the on-board spoofing proxy integrated with the special transport protocol can significantly enhance throughput performance on the high BER satellite link, the time needed to transfer files and the bandwidth used in reverse path are sharply reduced.展开更多
New wireless sensor network applications (e.g., military surveillance) require higher reliability than a simple best effort service could provide. Classical reliable transport protocols like Transmission Control Proto...New wireless sensor network applications (e.g., military surveillance) require higher reliability than a simple best effort service could provide. Classical reliable transport protocols like Transmission Control Protocol (TCP) are not well suited for wireless sensor networks due to both the characteristics of the network nodes (low computing power, strong energy constraints) and those of the main applications running on those nodes (low data rates). Recent researches present new transport protocols for wireless sensor networks providing various type of reliability and using new mechanisms for loss detection and recovery, and congestion control. This paper presents a survey on reliable transport protocol for WSNs.展开更多
The “Internet of Things” (IoT) refers to a set of intelligent “objects” that can communicate with each other directly or through a network. The IoT is the embodiment of the idea that everything can be connected an...The “Internet of Things” (IoT) refers to a set of intelligent “objects” that can communicate with each other directly or through a network. The IoT is the embodiment of the idea that everything can be connected anywhere and at any time. The concept can be applied to sectors such as e-health, e-government, automotive, geographic information systems, remote sensing, home networking, e-commerce and climate change mitigation. Unlike the Internet, the IoT has its own constraints, notably those linked to heterogeneity. This divergence is linked to different protocols, technologies and algorithms implemented in these connected objects for their interconnection. It should be noted that IoT devices can communicate with each other using different protocols and dedicated M2M (Machine to Machine) communication technologies. The aim of this work is to find solutions for optimising energy consumption during data exchanges between connected objects, with respect to certain constraints by using firstly this exchange for only Message Queuing Telemetry Transport (MQTT) and secondly the combination of the MQTT protocol and the Constrained Application Protocol (CoAP) protocol to check the quantity of the energy optimized. The MQTT protocol, for example, is one of the most widely used protocols for connected objects. Admittedly, this protocol consumes less energy, but in the situation of a very large number of users, the problem of saturation inevitably arises. In this article, we propose a solution of optimising energy consumption by combining the MQTT protocol with the CoAP protocol which can allow to use the standby mode contrary to the use of MQTT where the broker is always being turning. This solution has not yet been implemented but is being discussed. In this article, we’re going to use the joulemeter which is an application developed by Microsoft to measure and estimate the energy consumption of computers and applications. In our case, we take the example of the “Service Broker for network connections” of the Windows’s 10 Operating System, in my own computer to show the difference between the consumption of energy without the standby mode and with standby mode, because with the MQTT, the Broker’s MQTT is always on. Now, with the combination MQTT and CoAP, it is possible that we have standby mode and to compare these two cases in term of consumption of an energy. And to do it, we must use the joulemeter that we installed in our computer to simulate it. This is achieved by using the CoAP protocol combined with the MQTT protocol. The aim of our work is to reduce energy consumption in order to solve the problem of saturation of the MQTT by linking it to CoAP protocol by using Joulemeter mentioned above.展开更多
This paper discusses a transport protocol and its formal description techniques for local network. The transport layer function, the transport services and a transport protocol design in a local network architecture m...This paper discusses a transport protocol and its formal description techniques for local network. The transport layer function, the transport services and a transport protocol design in a local network architecture model are presented. A transport protocol specification using the finite state automata (FSA) is given. The correctness of the protocol is verified by using the reachability tree technique with respect to the protocol properties of completeness, deadlock and livelock freeness, termination and reachability.展开更多
Technologies for retransmission control and error correction are available for communications over the Internet to improve reliability of data. For communications that require the data reliability be ensured, TCP, whi...Technologies for retransmission control and error correction are available for communications over the Internet to improve reliability of data. For communications that require the data reliability be ensured, TCP, which performs retransmission control, is often employed. However, for environments and services where response confirmation and retransmission are difficult, error correction technologies are employed. Error correction is generally implemented on UDP, but the existing framework implemented on UDP frequently does not consider the maximum frame size of the data link layer and relegates data division to the IP module. The IP module divides data according to the maximum size for the data link, and the receiving IP module reconstructs the divided data. For a data link layer typified by the current Ethernet with an error detection function, the frame is often destroyed upon error detection. At the IP module, the specification allows destruction of the entire dataset whenever divided data necessary for reconstruction is incomplete. Consequently, an error in a single bit results in a total loss of data handed to the IP module, and thus error correction performance declines with the increase in data size handed to the IP module. The present study considers the MTU of the data link layer and proposes error correction protocol (ECP) over IP, which decreases the transfer data volume flowing to the data link layer by dividing data into blocks of appropriate size based on designated error correction code and its parameters (thus improving error correction performance) and assesses the performance of ECP. Experimental results demonstrate that performance is comparable or better than existing error correction frameworks. Results also show that when a specification not ensuring the reliability of the data link layer was employed, error correction was superior to existing frameworks on UDP.展开更多
DNS over HTTPS(DoH)协议是一种针对域名系统(DNS)的最新改进方案,然而用户可使用第三方DoH服务规避内网原有的监管,所以异常流量检测方法不再适用于检测DoH流量。针对该问题提出了一种DTESI算法。首先,基于信息熵将DoH流量作为异常流...DNS over HTTPS(DoH)协议是一种针对域名系统(DNS)的最新改进方案,然而用户可使用第三方DoH服务规避内网原有的监管,所以异常流量检测方法不再适用于检测DoH流量。针对该问题提出了一种DTESI算法。首先,基于信息熵将DoH流量作为异常流量从全部网络流量中筛选出来;然后,利用DoH服务器与同一客户端建立TLS连接时响应方式总是相同的特性,用指纹识别检测客户端与DoH服务器之间的TLS协商,确定DoH服务器身份;最后,使用Top-K抽样算法选出一定时段内网络中前K台活跃主机着重进行流量检测,使算法能应用于中大型组织的网络。实验结果表明,针对发现的异常流量,DTESI算法检测出的DoH服务提供商准确率超过94%。在此基础上比较了在不同K值下的算法检测时间和对网络中全部DoH流量的检测覆盖率,结果表明合理选择K值可以提升算法的整体效能。展开更多
随着电视系统由传统的串行数字接口(Serial Digital Interface,SDI)架构逐渐向网际互连协议(Internet Protocol,IP)架构转变,网络时钟协议(Network Time Protocol,NTP)、精确时间协议(Precision Time Protocol,PTP)、实时传输协议(Real-...随着电视系统由传统的串行数字接口(Serial Digital Interface,SDI)架构逐渐向网际互连协议(Internet Protocol,IP)架构转变,网络时钟协议(Network Time Protocol,NTP)、精确时间协议(Precision Time Protocol,PTP)、实时传输协议(Real-time Transport Protocol,RTP)时间戳(Timestamp)、电影和电视工程师协会(The Society of Motion Picture and Television Engineers,SMPTE)ST 2059等信号取代了传统SDI架构中的黑场(Black Burst,BB)信号,成为IP化电视系统的设备同步、流同步信号。基于此,详细介绍PTP的同步原理、RTP数据包的重要数据格式、RTP时间戳在视音频流同步中的原理及SMPTE ST 2059的定义及相关应用。展开更多
针对集中式基于网际互连协议的语音传输(Voice over Internet Protocol,VoIP)语音通信交换系统(Voice Communication Switching System,VCCS)的互操作性需求,提出一种基于VoIP技术的中继通信解决方案。在集中式VoIP通信架构的基础上构...针对集中式基于网际互连协议的语音传输(Voice over Internet Protocol,VoIP)语音通信交换系统(Voice Communication Switching System,VCCS)的互操作性需求,提出一种基于VoIP技术的中继通信解决方案。在集中式VoIP通信架构的基础上构建中继通信模型,结合局向管理、冠号管理、路由管理以及会议管理等模块的协同运行给出VoIP中继通信的业务处理流程,并详细阐述中继会议的核心模块。最后,通过两种异型语音通信交换系统的中继通信对比测试,验证了文章提出的VoIP中继通信方法的可靠性和互操作性。展开更多
基金Projects(60873265,60903222) supported by the National Natural Science Foundation of China Project(IRT0661) supported by the Program for Changjiang Scholars and Innovative Research Team in University of China
文摘An explicit congestion notification (ECN)-based distributed transport protocol,ARROW-WTCP (AcceleRate tRansmission towards Optimal Window size TCP for Wireless network),was proposed.The ARROW-WTCP enables feasible deployment of ARROW-TCP from wired to wireless networks by providing a joint design of source and router algorithms.The protocol obtains the actual capacity of the wireless channel by calculating the queue variation in base station (BS) and adjusts the congestion window by using the feedback from its bottleneck link.The simulation results show that the ARROW-WTCP achieves strong stability,max-min fairness in dynamic networks,fast convergence to efficiency without introducing much excess traffic,and almost full link utilization in the steady state.It outperforms the XCP-B (eXplicit Control Protocol Blind),the wireless version of XCP,in terms of stability,fairness,convergence and utilization in wireless networks.
基金supported by the National Natural Science Foundation of China (NSFC) under grant No. 61132002National Program on Key Basic Research Project of China (973 Program) under grant No. 2014CB340206+1 种基金the Creative Research Groups of NSFC under grant No. 61321061Aerospace Communications and Terminal Application Technologies Engineering Laboratory in Shenzhen under No.JCYJ20120619140254275
文摘This paper proposed a practical- feedback scheme for fountain codes based transportprotocol in space communications. In the proposed scheme, the sender is signaled by two types of acknowledgment （ACK） packets.Before decoding, packet loss probability isestimated on the receiver side and encapsulated intoa soft ACKand sent to the sender.After decoding,decoding results are encapsulated into hard ACKsandsent to the sender. There are two contributionsin the proposed scheme： 1. Empl layer calculation instead layer statistics to estimate oying physical of application the packet loss probability of space channel, which can improvethe accuracy and practicality. 2. A cascade overhead-failure probability relationship between the sender and the receiver has been analyzed to help determine the exact numberof packetsneeded byfountain decoding.Simulations show that for space communications,compared with the existing space transport protocols, fountain codes based transport protoeolwith the proposed schemecan not only ensure transmission reliability, but also greatly improvelink utilization.
文摘As a result of the exponential growing rate of worldwide Internet usage, satellite systems are required to support broadband Internet applications. The transmission control protocol （TCP） which is widely used in the Internet, performs very well on wired networks. However, in the case of satellite channels, clue to the delay and transmission errors, TCP performance degrades significantly and bandwidth of satellite links can not be fully utilized. To improve the TCP performance, a new idea of placing a TCP spoofing proxy in the satellite is considered. A Novel Satellite Transport Protocol （NSTP） which takes advantage of the special properties of the satellite channel is also proposed. By using simulation, as compared with traditional TCPs, the on-board spoofing proxy integrated with the special transport protocol can significantly enhance throughput performance on the high BER satellite link, the time needed to transfer files and the bandwidth used in reverse path are sharply reduced.
文摘New wireless sensor network applications (e.g., military surveillance) require higher reliability than a simple best effort service could provide. Classical reliable transport protocols like Transmission Control Protocol (TCP) are not well suited for wireless sensor networks due to both the characteristics of the network nodes (low computing power, strong energy constraints) and those of the main applications running on those nodes (low data rates). Recent researches present new transport protocols for wireless sensor networks providing various type of reliability and using new mechanisms for loss detection and recovery, and congestion control. This paper presents a survey on reliable transport protocol for WSNs.
文摘The “Internet of Things” (IoT) refers to a set of intelligent “objects” that can communicate with each other directly or through a network. The IoT is the embodiment of the idea that everything can be connected anywhere and at any time. The concept can be applied to sectors such as e-health, e-government, automotive, geographic information systems, remote sensing, home networking, e-commerce and climate change mitigation. Unlike the Internet, the IoT has its own constraints, notably those linked to heterogeneity. This divergence is linked to different protocols, technologies and algorithms implemented in these connected objects for their interconnection. It should be noted that IoT devices can communicate with each other using different protocols and dedicated M2M (Machine to Machine) communication technologies. The aim of this work is to find solutions for optimising energy consumption during data exchanges between connected objects, with respect to certain constraints by using firstly this exchange for only Message Queuing Telemetry Transport (MQTT) and secondly the combination of the MQTT protocol and the Constrained Application Protocol (CoAP) protocol to check the quantity of the energy optimized. The MQTT protocol, for example, is one of the most widely used protocols for connected objects. Admittedly, this protocol consumes less energy, but in the situation of a very large number of users, the problem of saturation inevitably arises. In this article, we propose a solution of optimising energy consumption by combining the MQTT protocol with the CoAP protocol which can allow to use the standby mode contrary to the use of MQTT where the broker is always being turning. This solution has not yet been implemented but is being discussed. In this article, we’re going to use the joulemeter which is an application developed by Microsoft to measure and estimate the energy consumption of computers and applications. In our case, we take the example of the “Service Broker for network connections” of the Windows’s 10 Operating System, in my own computer to show the difference between the consumption of energy without the standby mode and with standby mode, because with the MQTT, the Broker’s MQTT is always on. Now, with the combination MQTT and CoAP, it is possible that we have standby mode and to compare these two cases in term of consumption of an energy. And to do it, we must use the joulemeter that we installed in our computer to simulate it. This is achieved by using the CoAP protocol combined with the MQTT protocol. The aim of our work is to reduce energy consumption in order to solve the problem of saturation of the MQTT by linking it to CoAP protocol by using Joulemeter mentioned above.
文摘This paper discusses a transport protocol and its formal description techniques for local network. The transport layer function, the transport services and a transport protocol design in a local network architecture model are presented. A transport protocol specification using the finite state automata (FSA) is given. The correctness of the protocol is verified by using the reachability tree technique with respect to the protocol properties of completeness, deadlock and livelock freeness, termination and reachability.
文摘Technologies for retransmission control and error correction are available for communications over the Internet to improve reliability of data. For communications that require the data reliability be ensured, TCP, which performs retransmission control, is often employed. However, for environments and services where response confirmation and retransmission are difficult, error correction technologies are employed. Error correction is generally implemented on UDP, but the existing framework implemented on UDP frequently does not consider the maximum frame size of the data link layer and relegates data division to the IP module. The IP module divides data according to the maximum size for the data link, and the receiving IP module reconstructs the divided data. For a data link layer typified by the current Ethernet with an error detection function, the frame is often destroyed upon error detection. At the IP module, the specification allows destruction of the entire dataset whenever divided data necessary for reconstruction is incomplete. Consequently, an error in a single bit results in a total loss of data handed to the IP module, and thus error correction performance declines with the increase in data size handed to the IP module. The present study considers the MTU of the data link layer and proposes error correction protocol (ECP) over IP, which decreases the transfer data volume flowing to the data link layer by dividing data into blocks of appropriate size based on designated error correction code and its parameters (thus improving error correction performance) and assesses the performance of ECP. Experimental results demonstrate that performance is comparable or better than existing error correction frameworks. Results also show that when a specification not ensuring the reliability of the data link layer was employed, error correction was superior to existing frameworks on UDP.
文摘DNS over HTTPS(DoH)协议是一种针对域名系统(DNS)的最新改进方案,然而用户可使用第三方DoH服务规避内网原有的监管,所以异常流量检测方法不再适用于检测DoH流量。针对该问题提出了一种DTESI算法。首先,基于信息熵将DoH流量作为异常流量从全部网络流量中筛选出来;然后,利用DoH服务器与同一客户端建立TLS连接时响应方式总是相同的特性,用指纹识别检测客户端与DoH服务器之间的TLS协商,确定DoH服务器身份;最后,使用Top-K抽样算法选出一定时段内网络中前K台活跃主机着重进行流量检测,使算法能应用于中大型组织的网络。实验结果表明,针对发现的异常流量,DTESI算法检测出的DoH服务提供商准确率超过94%。在此基础上比较了在不同K值下的算法检测时间和对网络中全部DoH流量的检测覆盖率,结果表明合理选择K值可以提升算法的整体效能。
文摘随着电视系统由传统的串行数字接口(Serial Digital Interface,SDI)架构逐渐向网际互连协议(Internet Protocol,IP)架构转变,网络时钟协议(Network Time Protocol,NTP)、精确时间协议(Precision Time Protocol,PTP)、实时传输协议(Real-time Transport Protocol,RTP)时间戳(Timestamp)、电影和电视工程师协会(The Society of Motion Picture and Television Engineers,SMPTE)ST 2059等信号取代了传统SDI架构中的黑场(Black Burst,BB)信号,成为IP化电视系统的设备同步、流同步信号。基于此,详细介绍PTP的同步原理、RTP数据包的重要数据格式、RTP时间戳在视音频流同步中的原理及SMPTE ST 2059的定义及相关应用。
文摘针对集中式基于网际互连协议的语音传输(Voice over Internet Protocol,VoIP)语音通信交换系统(Voice Communication Switching System,VCCS)的互操作性需求,提出一种基于VoIP技术的中继通信解决方案。在集中式VoIP通信架构的基础上构建中继通信模型,结合局向管理、冠号管理、路由管理以及会议管理等模块的协同运行给出VoIP中继通信的业务处理流程,并详细阐述中继会议的核心模块。最后,通过两种异型语音通信交换系统的中继通信对比测试,验证了文章提出的VoIP中继通信方法的可靠性和互操作性。
