Ad Hoc网络具有拓扑动态变化,网络节点自身能量、带宽等性能受限的特点,会导致路由不稳定性的增加和网络性能的下降,因而寻找稳定路由,提高网络性能是Ad Hoc网络研究的一个重要课题。提出了一种基于稳定度的QoS路由协议,并利用得到的多...Ad Hoc网络具有拓扑动态变化,网络节点自身能量、带宽等性能受限的特点,会导致路由不稳定性的增加和网络性能的下降,因而寻找稳定路由,提高网络性能是Ad Hoc网络研究的一个重要课题。提出了一种基于稳定度的QoS路由协议,并利用得到的多条节点不相交路径实现了负载均衡,最后通过NS-2仿真验证了协议的性能。展开更多
Ad hoc网络是指由一组带有无线通信收发装置的移动节点组成的一个多跳、自组织、无中心网络。作为一个不需要固定基础设施特殊的无线网络,它在民用、军事与测量通信领域占据一席之地,成为当前网络研究的热点。本论文的主要研究目标是利...Ad hoc网络是指由一组带有无线通信收发装置的移动节点组成的一个多跳、自组织、无中心网络。作为一个不需要固定基础设施特殊的无线网络,它在民用、军事与测量通信领域占据一席之地,成为当前网络研究的热点。本论文的主要研究目标是利用国内外现有的相关研究成果,对Ad hoc自组网常用的AODV路由协议进行节能的研究,使其达到能耗低,长时间工作的目标,以应用在测试与监控中。最后通过仿真比较得以证明其改进的有效性。展开更多
There is a lack of appropriate guidelines for realistic user traces, mobility models, routing protocols, considerations of real-life challenges, etc. for general-purpose mobile ad hoc networks (MANET). In this paper...There is a lack of appropriate guidelines for realistic user traces, mobility models, routing protocols, considerations of real-life challenges, etc. for general-purpose mobile ad hoc networks (MANET). In this paper, four laptops are used in an open field environment in four scenarios to evaluate the performances of Internet control message protocol (ICMP) based ping and transmission control protocol (TCP) based streaming video applications using optimised link state routing (OLSR) implementation in an IEEE 802.11g wireless network. Corresponding simulations are developed in Network Simulator ns-2 by setting simulation parameters according to the real experiments. Difficulties faced to regenerate real-life scenarios have been discussed and the gaps between reality and simulation are identified. A setup guideline to produce realistic simulation results has been established.展开更多
为了改善移动Ad Hoc网络环境下TCP的性能,对AODV的改进协议OAODV协议做了一定的修订,得到E-OAODV(Enhanced Opti mal Ad Hoc On-demand Distant Vector)协议。该协议通过在路由失效时使用来自目的节点的ACK应答信号所包含的路由信息来...为了改善移动Ad Hoc网络环境下TCP的性能,对AODV的改进协议OAODV协议做了一定的修订,得到E-OAODV(Enhanced Opti mal Ad Hoc On-demand Distant Vector)协议。该协议通过在路由失效时使用来自目的节点的ACK应答信号所包含的路由信息来尝试继续传输数据,同时通过对OAODV和TCP两者的修订来实现在路由重建后尽可能地恢复因路由失效所丢失的数据包。NS-2下的仿真结果表明,E-OAODV对断线点离源节点较近的情况下的TCP性能有较显著的改善,尤其在路由总跳数较大时。展开更多
文摘There is a lack of appropriate guidelines for realistic user traces, mobility models, routing protocols, considerations of real-life challenges, etc. for general-purpose mobile ad hoc networks (MANET). In this paper, four laptops are used in an open field environment in four scenarios to evaluate the performances of Internet control message protocol (ICMP) based ping and transmission control protocol (TCP) based streaming video applications using optimised link state routing (OLSR) implementation in an IEEE 802.11g wireless network. Corresponding simulations are developed in Network Simulator ns-2 by setting simulation parameters according to the real experiments. Difficulties faced to regenerate real-life scenarios have been discussed and the gaps between reality and simulation are identified. A setup guideline to produce realistic simulation results has been established.
文摘为了改善移动Ad Hoc网络环境下TCP的性能,对AODV的改进协议OAODV协议做了一定的修订,得到E-OAODV(Enhanced Opti mal Ad Hoc On-demand Distant Vector)协议。该协议通过在路由失效时使用来自目的节点的ACK应答信号所包含的路由信息来尝试继续传输数据,同时通过对OAODV和TCP两者的修订来实现在路由重建后尽可能地恢复因路由失效所丢失的数据包。NS-2下的仿真结果表明,E-OAODV对断线点离源节点较近的情况下的TCP性能有较显著的改善,尤其在路由总跳数较大时。