As one of the most promising next-generation access network (EPON) should pay more attention to its quality of service (QoS), techniques, the user-oriented Ethernet passive optical network However, now the EPON ad...As one of the most promising next-generation access network (EPON) should pay more attention to its quality of service (QoS), techniques, the user-oriented Ethernet passive optical network However, now the EPON adopts mostly differentiated services model (Diffserv) that only provides quality control on traffic aggregation, whereas, the quality of user session cannot be guaranteed when the network is overloaded with substantial connections. This article proposes to apply integrated services model (Intserv) in Diffserv-based EPON, which uses per-flow processing to guarantee QoS. In the simulation, a framework of combined Diffserv and Intserv model is employed in an EPON system, with a dynamic bandwidth allocation algorithm that adapts to it. The simulation results demonstrate that the EPON system with the combined models can provide more flexible, various control for user-oriented service quality.展开更多
介绍了一种端到端的QoS架构模型:Intserv over Diffserv,研究了它的映射机制,构造了一种映射函数和网络配置,然后以服务流的吞吐量、路由器中的队列长度和分组的丢包率作为衡量参数,通过具体的仿真评估了此模型中的IntServ服务通过Diffs...介绍了一种端到端的QoS架构模型:Intserv over Diffserv,研究了它的映射机制,构造了一种映射函数和网络配置,然后以服务流的吞吐量、路由器中的队列长度和分组的丢包率作为衡量参数,通过具体的仿真评估了此模型中的IntServ服务通过Diffserv区时所能获得的QoS。展开更多
Internet real-time multimedia communication brings a further challenge to Quality of Service(QoS).A higher QoS in communication is required increasingly.As a new framework for providing QoS services,Differentiated Ser...Internet real-time multimedia communication brings a further challenge to Quality of Service(QoS).A higher QoS in communication is required increasingly.As a new framework for providing QoS services,Differentiated Services (DiffServ)is undergoing a speedily standardization process at the IETF.DiffServ not only can offer classified level of services,but also can provide guaranteed QoS in a certain extent.In order to provide QoS,DiffServ must be properly configured.The traditional DiffServ mechanism provides classifier for edge router to mark the different traffic streams,and then the core router uses different Drop Packet Mechanisms to drop packets or transmit data packets according to these classified markers.When multiple edge routers or other core routers transmit data packets high speedily to a single core router,the core router will emerge bottleneck bandwidth.The most valid solution to this problem is that the edge router adopts drop packet mechanism.This paper proposes an Modified Edge Router Mechanism that let the edge router achieve marking,dropping and transmitting packets of hybrid traffic streams based on DiffServ in a given bandwidth,the core router will only transmits packets but won’t drop packets.By the simulation of ns2,the modified mechanism ensure the QoS of high priority traffics and simplify the core router,it is a valid method to solve the congestion of the core router.展开更多
融合了多协议标记交换 (Multiprotocol L abel Switching,MPL S)和区分服务 (Differentiated Services,Diff Serv)技术 ,建立了 Diff Serv over MPL S模型 ,研究了在模型上承载区分服务 ,以实现端到端的服务质量(Quality of Service,Qo...融合了多协议标记交换 (Multiprotocol L abel Switching,MPL S)和区分服务 (Differentiated Services,Diff Serv)技术 ,建立了 Diff Serv over MPL S模型 ,研究了在模型上承载区分服务 ,以实现端到端的服务质量(Quality of Service,Qo S)的技术 .详细描述了其中的重要概念、分组的转发处理过程及基于约束路由的标记分发协议 (Constraint- based Routing L abel Distribution Protocol,CR- L DP)的扩展细节 .展开更多
基金supported by the National Basic Research Program of China(2007CB310705)the National Natural Science Foundation of China(60772024)+2 种基金the Hi-Tech Research and Development Program of China(2007AA01Z255)PCSIRT(IRT0609)ISTCP(2006DFA 11040)
摘要As one of the most promising next-generation access network (EPON) should pay more attention to its quality of service (QoS), techniques, the user-oriented Ethernet passive optical network However, now the EPON adopts mostly differentiated services model (Diffserv) that only provides quality control on traffic aggregation, whereas, the quality of user session cannot be guaranteed when the network is overloaded with substantial connections. This article proposes to apply integrated services model (Intserv) in Diffserv-based EPON, which uses per-flow processing to guarantee QoS. In the simulation, a framework of combined Diffserv and Intserv model is employed in an EPON system, with a dynamic bandwidth allocation algorithm that adapts to it. The simulation results demonstrate that the EPON system with the combined models can provide more flexible, various control for user-oriented service quality.
基金supported by the National Natural Science Foundation of China:(No60572093)the Specialized Research Fund for the Doctoral Program of Higher Education(No20050004016)NSFC-KOSEF Joint Research Project of China and Korea,and the CDSN,GIST
摘要Internet real-time multimedia communication brings a further challenge to Quality of Service(QoS).A higher QoS in communication is required increasingly.As a new framework for providing QoS services,Differentiated Services (DiffServ)is undergoing a speedily standardization process at the IETF.DiffServ not only can offer classified level of services,but also can provide guaranteed QoS in a certain extent.In order to provide QoS,DiffServ must be properly configured.The traditional DiffServ mechanism provides classifier for edge router to mark the different traffic streams,and then the core router uses different Drop Packet Mechanisms to drop packets or transmit data packets according to these classified markers.When multiple edge routers or other core routers transmit data packets high speedily to a single core router,the core router will emerge bottleneck bandwidth.The most valid solution to this problem is that the edge router adopts drop packet mechanism.This paper proposes an Modified Edge Router Mechanism that let the edge router achieve marking,dropping and transmitting packets of hybrid traffic streams based on DiffServ in a given bandwidth,the core router will only transmits packets but won’t drop packets.By the simulation of ns2,the modified mechanism ensure the QoS of high priority traffics and simplify the core router,it is a valid method to solve the congestion of the core router.
摘要融合了多协议标记交换 (Multiprotocol L abel Switching,MPL S)和区分服务 (Differentiated Services,Diff Serv)技术 ,建立了 Diff Serv over MPL S模型 ,研究了在模型上承载区分服务 ,以实现端到端的服务质量(Quality of Service,Qo S)的技术 .详细描述了其中的重要概念、分组的转发处理过程及基于约束路由的标记分发协议 (Constraint- based Routing L abel Distribution Protocol,CR- L DP)的扩展细节 .