Recently, location-based routings in wireless sensor networks (WSNs) are attracting a lot of interest in the research community, especially because of its scalability. In location-based routing, the network size is sc...Recently, location-based routings in wireless sensor networks (WSNs) are attracting a lot of interest in the research community, especially because of its scalability. In location-based routing, the network size is scalable without increasing the signalling overhead as routing decisions are inherently localized. Here, each node is aware of its position in the network through some positioning device like GPS and uses this information in the routing mechanism. In this paper, we first discuss the basics of WSNs including the architecture of the network, energy consumption for the components of a typical sensor node, and draw a detailed picture of classification of location-based routing protocols. Then, we present a systematic and comprehensive taxonomy of location-based routing protocols, mostly for sensor networks. All the schemes are subsequently discussed in depth. Finally, we conclude the paper with some insights on potential research directions for location-based routing in WSNs.展开更多
In Delay Tolerant Networks （DTNs）, the offiine users can, through the encountering nodes, use the specific peer-to-peer message routing approach to deliver messages to the destination. Thus, it solves the problem th...In Delay Tolerant Networks （DTNs）, the offiine users can, through the encountering nodes, use the specific peer-to-peer message routing approach to deliver messages to the destination. Thus, it solves the problem that users have the demands to deliver messages while they are temporarily not able to connect to the Internet. Therefore, by the characteristics of DTNs, people who are not online can still query some location based information, with the help of users using the same service in the nearby area. In this paper, we proposed a location-based content search approach. Based on the concept of three-tier area and hybrid node types, we presented four strategies to solve the query problem, namely, Data Replication, Query Replication, Data Reply, and Data Synchronization strategies. Especially we proposed a Message Queue Selection algorithm for message transferring. The priority concept is set associated with every message such that the most ＂important＂ one could be sent first. In this way, it can increase the query success ratio and reduce the query delay time. Finally, we evaluated our approach, and compared with other routing schemes. The simulation results showed that our proposed approach had better query efficiency and shorter delay.展开更多
车载网VANETs(Vehicular ad hoc networks)属于高速移动的无线网络,可供车辆安全、交通监测以及其他的商业服务的应用。然而,为此,提出混合式的位VANETs中车辆的快速移动导致通信链路频繁地断裂,增加路由开销,降低了可扩展性。议地理位...车载网VANETs(Vehicular ad hoc networks)属于高速移动的无线网络,可供车辆安全、交通监测以及其他的商业服务的应用。然而,为此,提出混合式的位VANETs中车辆的快速移动导致通信链路频繁地断裂,增加路由开销,降低了可扩展性。议地理位置路由的特点。HLAR(Hybrid location-based ad hoc routing)。HLAR结合了反应式路由、HLAR克服了反应式路由的扩展性问题,并改善了地理位置路由对位置误差的敏感性。同时,通过理论分析,量可扩展性,并推导了路由开销的表达式。通过分析、仿真表明,提出的路由协议具有很好的扩展性,并降低了路由开销。在仿真中引入位置误差因子,结果表明。同时,与同类的其他协议相比,输时延方面HLAR到对位置误差具有很强的鲁棒性HLAR在数据传输率、端到端传提升。展开更多
基于位置服务业务的迅猛发展趋势,研究并设计实现了基于J2EE的位置服务平台(Location Based Service,LBS)。平台采用了开放式的J2EE标准,重点规划设计了LBS平台各子模块的划分、相互的接口函数、用户请求协议规范等,具体实现了用户请求...基于位置服务业务的迅猛发展趋势,研究并设计实现了基于J2EE的位置服务平台(Location Based Service,LBS)。平台采用了开放式的J2EE标准,重点规划设计了LBS平台各子模块的划分、相互的接口函数、用户请求协议规范等,具体实现了用户请求综合处理子模块、用户认证管理子模块、GIS适配层子模块和后台管理子模块,最终通过Web和Wap环境进行了测试,结果表明LBS平台运行良好。展开更多
文摘Recently, location-based routings in wireless sensor networks (WSNs) are attracting a lot of interest in the research community, especially because of its scalability. In location-based routing, the network size is scalable without increasing the signalling overhead as routing decisions are inherently localized. Here, each node is aware of its position in the network through some positioning device like GPS and uses this information in the routing mechanism. In this paper, we first discuss the basics of WSNs including the architecture of the network, energy consumption for the components of a typical sensor node, and draw a detailed picture of classification of location-based routing protocols. Then, we present a systematic and comprehensive taxonomy of location-based routing protocols, mostly for sensor networks. All the schemes are subsequently discussed in depth. Finally, we conclude the paper with some insights on potential research directions for location-based routing in WSNs.
文摘In Delay Tolerant Networks （DTNs）, the offiine users can, through the encountering nodes, use the specific peer-to-peer message routing approach to deliver messages to the destination. Thus, it solves the problem that users have the demands to deliver messages while they are temporarily not able to connect to the Internet. Therefore, by the characteristics of DTNs, people who are not online can still query some location based information, with the help of users using the same service in the nearby area. In this paper, we proposed a location-based content search approach. Based on the concept of three-tier area and hybrid node types, we presented four strategies to solve the query problem, namely, Data Replication, Query Replication, Data Reply, and Data Synchronization strategies. Especially we proposed a Message Queue Selection algorithm for message transferring. The priority concept is set associated with every message such that the most ＂important＂ one could be sent first. In this way, it can increase the query success ratio and reduce the query delay time. Finally, we evaluated our approach, and compared with other routing schemes. The simulation results showed that our proposed approach had better query efficiency and shorter delay.
文摘车载网VANETs(Vehicular ad hoc networks)属于高速移动的无线网络,可供车辆安全、交通监测以及其他的商业服务的应用。然而,为此,提出混合式的位VANETs中车辆的快速移动导致通信链路频繁地断裂,增加路由开销,降低了可扩展性。议地理位置路由的特点。HLAR(Hybrid location-based ad hoc routing)。HLAR结合了反应式路由、HLAR克服了反应式路由的扩展性问题,并改善了地理位置路由对位置误差的敏感性。同时,通过理论分析,量可扩展性,并推导了路由开销的表达式。通过分析、仿真表明,提出的路由协议具有很好的扩展性,并降低了路由开销。在仿真中引入位置误差因子,结果表明。同时,与同类的其他协议相比,输时延方面HLAR到对位置误差具有很强的鲁棒性HLAR在数据传输率、端到端传提升。
文摘基于位置服务业务的迅猛发展趋势,研究并设计实现了基于J2EE的位置服务平台(Location Based Service,LBS)。平台采用了开放式的J2EE标准,重点规划设计了LBS平台各子模块的划分、相互的接口函数、用户请求协议规范等,具体实现了用户请求综合处理子模块、用户认证管理子模块、GIS适配层子模块和后台管理子模块,最终通过Web和Wap环境进行了测试,结果表明LBS平台运行良好。
