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
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
为提高移动自组网的网络性能和推进Semi-TCP方法的实际应用,提出基于路由协议的Semi-TCP网络层逐跳拥塞控制实现方法。通过在网络层的路由协议中加入拥塞信息广播机制,控制节点对数据包的发送频率,保持链路高速传输数据的同时,降低拥塞...为提高移动自组网的网络性能和推进Semi-TCP方法的实际应用,提出基于路由协议的Semi-TCP网络层逐跳拥塞控制实现方法。通过在网络层的路由协议中加入拥塞信息广播机制,控制节点对数据包的发送频率,保持链路高速传输数据的同时,降低拥塞程度。在EXata仿真平台进行了验证,在设计的动态拓扑实验中,文中方法的吞吐量相比TCP New Reno提高了169.57%,在引入多TCP应用竞争链路后比原Semi-TCP方法提高19.52%,证明了文中方法的有效性。展开更多
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。
文摘为提高移动自组网的网络性能和推进Semi-TCP方法的实际应用,提出基于路由协议的Semi-TCP网络层逐跳拥塞控制实现方法。通过在网络层的路由协议中加入拥塞信息广播机制,控制节点对数据包的发送频率,保持链路高速传输数据的同时,降低拥塞程度。在EXata仿真平台进行了验证,在设计的动态拓扑实验中,文中方法的吞吐量相比TCP New Reno提高了169.57%,在引入多TCP应用竞争链路后比原Semi-TCP方法提高19.52%,证明了文中方法的有效性。