A quality of service （QoS） or constraint-based routing selection needs to find a path subject to multiple constraints through a network. The problem of finding such a path is known as the multi-constrained path （MC...A quality of service （QoS） or constraint-based routing selection needs to find a path subject to multiple constraints through a network. The problem of finding such a path is known as the multi-constrained path （MCP） problem, and has been proven to be NP-complete that cannot be exactly solved in a polynomial time. The NPC problem is converted into a multiobjective optimization problem with constraints to be solved with a genetic algorithm. Based on the Pareto optimum, a constrained routing computation method is proposed to generate a set of nondominated optimal routes with the genetic algorithm mechanism. The convergence and time complexity of the novel algorithm is analyzed. Experimental results show that multiobjective evolution is highly responsive and competent for the Pareto optimum-based route selection. When this method is applied to a MPLS and metropolitan-area network, it will be capable of optimizing the transmission performance.展开更多
This work considers those road networks in which there are multi-route choices for bifurcation-destination(or origin-destination) pairs, and designs a real-time variable message sign(VMS)-based routing control strateg...This work considers those road networks in which there are multi-route choices for bifurcation-destination(or origin-destination) pairs, and designs a real-time variable message sign(VMS)-based routing control strategy in the model predictive control(MPC) framework. The VMS route recommendation provided by the traffic management authority is directly considered as the control variable, and the routing control model is established, in which a multi-dimensional control vector is introduced to describe the influence of route recommendations on flow distribution. In the MPC framework, a system optimum routing strategy with the constraints regarding drivers' acceptability with recommended routes is designed, which can not only meet the traffic management authority's control requirement but also improve drivers' satisfaction with the route guidance system. The simulation carried out shows that the proposed routing control can effectively mitigate traffic congestion, reduces followers' time delay, and improves drivers' satisfaction with routing control in road networks.展开更多
下一代互联网NGI(next generation Intemet)需要提供服务质量QoS(quality of service)路由能力.由于NGI网络状态难以精确测量与表达,因此,QoS路由基于的信息应该是模糊的.随着网络运营的渐趋商业化,付费上网要求实现QoS计费,而网络提供...下一代互联网NGI(next generation Intemet)需要提供服务质量QoS(quality of service)路由能力.由于NGI网络状态难以精确测量与表达,因此,QoS路由基于的信息应该是模糊的.随着网络运营的渐趋商业化,付费上网要求实现QoS计费,而网络提供方与用户的利益冲突要求实现效用双赢.设计了一种基于模糊积分和博弈论的QoS组播路由机制.该机制由边评判、博弈分析和组播路由树建立算法组成,基于模糊积分和适合隶属度函数对边进行模糊综合评判,通过博弈分析确定网络提供方与用户在边上的效用能否达到Nash均衡,通过组播路由树建立算法使得在建立的组播路由树上不仅用户QoS要求得到满足,而且网络提供方效用与用户效用达到或接近Nash均衡下的Pareto最优.仿真结果表明,与QoSMIC等机制相比,该机制具有较好的性能.展开更多
下一代互联网NGI(Next Generation Internet)需要提供服务质量QoS(Quality of Service)路由能力,支持总最佳连接ABC(Always Best Connected).但是,由于链路状态的难以精确测量与用户QoS需求的难以准确表达,因此QoS路由基于的信息实际上...下一代互联网NGI(Next Generation Internet)需要提供服务质量QoS(Quality of Service)路由能力,支持总最佳连接ABC(Always Best Connected).但是,由于链路状态的难以精确测量与用户QoS需求的难以准确表达,因此QoS路由基于的信息实际上是模糊的.同时,在网络运营日益商业化的环境下,支持ABC需要兼顾用户和网络提供方利益,考虑双方效用共赢.为此,文中引入模糊数学、概率论和博弈论知识,设计了一种ABC支持型QoS单播路由机制.该机制采用区间形式描述用户QoS需求和边(链路)参数,引入用户满意度和边评价,通过博弈分析,基于人工鱼群算法,寻找使用户和网络提供方效用达到或接近Nash均衡下Pareto最优的QoS单播路径.仿真结果表明,该机制是可行和有效的.展开更多
基金the Natural Science Foundation of Anhui Province of China (050420212)the Excellent Youth Science and Technology Foundation of Anhui Province of China (04042069).
文摘A quality of service （QoS） or constraint-based routing selection needs to find a path subject to multiple constraints through a network. The problem of finding such a path is known as the multi-constrained path （MCP） problem, and has been proven to be NP-complete that cannot be exactly solved in a polynomial time. The NPC problem is converted into a multiobjective optimization problem with constraints to be solved with a genetic algorithm. Based on the Pareto optimum, a constrained routing computation method is proposed to generate a set of nondominated optimal routes with the genetic algorithm mechanism. The convergence and time complexity of the novel algorithm is analyzed. Experimental results show that multiobjective evolution is highly responsive and competent for the Pareto optimum-based route selection. When this method is applied to a MPLS and metropolitan-area network, it will be capable of optimizing the transmission performance.
基金Projects(61304203,51409157)supported by the National Natural Science Foundation of ChinaProject(12ZR1444800)supported by the Natural Science Foundation of Shanghai,China
文摘This work considers those road networks in which there are multi-route choices for bifurcation-destination(or origin-destination) pairs, and designs a real-time variable message sign(VMS)-based routing control strategy in the model predictive control(MPC) framework. The VMS route recommendation provided by the traffic management authority is directly considered as the control variable, and the routing control model is established, in which a multi-dimensional control vector is introduced to describe the influence of route recommendations on flow distribution. In the MPC framework, a system optimum routing strategy with the constraints regarding drivers' acceptability with recommended routes is designed, which can not only meet the traffic management authority's control requirement but also improve drivers' satisfaction with the route guidance system. The simulation carried out shows that the proposed routing control can effectively mitigate traffic congestion, reduces followers' time delay, and improves drivers' satisfaction with routing control in road networks.
基金the National Natural Science Foundation of China under Grant Nos.6067315970671020(国家自然科学基金)+5 种基金the National High-Tech Research and Development Plan of China under Grant No.2006AA01Z214(国家高技术研究发展计划(863))the Program for New Century Excellent Talents in University of China under Grant No.NCET-05-0289(新世纪优秀人才支持计划)the Key Project of Chinese Ministry of Education under Grant No108040(国家教育部科学技术研究重点项目)the Specialized Research Fund for the Doctoral Program of Higher Education of China under Grant No.20060145012(高等学校博士学科点专项科研基金)the Natural Science Foundation of Liaoning Province of China under Grant No.20062022(辽宁省自然科学基金)
文摘下一代互联网NGI(next generation Intemet)需要提供服务质量QoS(quality of service)路由能力.由于NGI网络状态难以精确测量与表达,因此,QoS路由基于的信息应该是模糊的.随着网络运营的渐趋商业化,付费上网要求实现QoS计费,而网络提供方与用户的利益冲突要求实现效用双赢.设计了一种基于模糊积分和博弈论的QoS组播路由机制.该机制由边评判、博弈分析和组播路由树建立算法组成,基于模糊积分和适合隶属度函数对边进行模糊综合评判,通过博弈分析确定网络提供方与用户在边上的效用能否达到Nash均衡,通过组播路由树建立算法使得在建立的组播路由树上不仅用户QoS要求得到满足,而且网络提供方效用与用户效用达到或接近Nash均衡下的Pareto最优.仿真结果表明,与QoSMIC等机制相比,该机制具有较好的性能.
文摘下一代互联网NGI(Next Generation Internet)需要提供服务质量QoS(Quality of Service)路由能力,支持总最佳连接ABC(Always Best Connected).但是,由于链路状态的难以精确测量与用户QoS需求的难以准确表达,因此QoS路由基于的信息实际上是模糊的.同时,在网络运营日益商业化的环境下,支持ABC需要兼顾用户和网络提供方利益,考虑双方效用共赢.为此,文中引入模糊数学、概率论和博弈论知识,设计了一种ABC支持型QoS单播路由机制.该机制采用区间形式描述用户QoS需求和边(链路)参数,引入用户满意度和边评价,通过博弈分析,基于人工鱼群算法,寻找使用户和网络提供方效用达到或接近Nash均衡下Pareto最优的QoS单播路径.仿真结果表明,该机制是可行和有效的.
