A new scheduling algorithm, which aims to provide proportional and controllable QoS (Quality of Service) in terms of burst loss probability for OBS (Optical Burst Switching) networks, is proposed on the ba- sis of a s...A new scheduling algorithm, which aims to provide proportional and controllable QoS (Quality of Service) in terms of burst loss probability for OBS (Optical Burst Switching) networks, is proposed on the ba- sis of a survey of QoS schemes in current OBS networks. With simulations, performance analysis and com- parisons are carried out in detail. The results show that, in the proposed scheme, burst loss probabilities are proportional to the given factors and the control of QoS performance can be achieved with better performance. This scheme will be beneficial to the OBS network management and the tariff policy making.展开更多
In recent years,various internet architectures,such as Integrated Services(IntServ),Differentiated Services(DiffServ),Time Sensitive Networking(TSN)and Deterministic Networking(DetNet),have been proposed to meet the q...In recent years,various internet architectures,such as Integrated Services(IntServ),Differentiated Services(DiffServ),Time Sensitive Networking(TSN)and Deterministic Networking(DetNet),have been proposed to meet the quality-of-service(QoS)requirements of different network services.Concurrently,network calculus has found widespread application in network modeling and QoS analysis.Network calculus abstracts the details of how nodes or networks process data packets using the concept of service curves.This paper summarizes the service curves for typical scheduling algorithms,including Strict Priority(SP),Round Robin(RR),Cycling Queuing and Forwarding(CQF),Time Aware Shaper(TAS),Credit Based Shaper(CBS),and Asynchronous Traffic Shaper(ATS).It introduces the theory of network calculus and then provides an overview of various scheduling algorithms and their associated service curves.The delay bound analysis for different scheduling algorithms in specific scenarios is also conducted for more insights.展开更多
面对国内外大型公有云供应商的激烈竞争,中小云厂商的生存难度加大。为此,建立一个基于相互合作的云联盟成为了这些厂商的一种可行策略。然而,在追求个体最大利益和保障联盟整体服务质量(quality of service,QoS)之间存在着复杂的博弈...面对国内外大型公有云供应商的激烈竞争,中小云厂商的生存难度加大。为此,建立一个基于相互合作的云联盟成为了这些厂商的一种可行策略。然而,在追求个体最大利益和保障联盟整体服务质量(quality of service,QoS)之间存在着复杂的博弈关系。针对上述问题,一种基于QoS的云联盟模型被提出,其涵盖云计算的三层架构。在应用层至虚拟层,引入了一种基于差分进化(differential evolution,DE)算法的创新任务分配策略,专门用于处理多QoS任务分配问题。在虚拟层至物理层,设计了合作与竞争并存的虚拟机迁移模型,适用于在云联盟博弈计算环境下实现虚拟机迁移的能耗与QoS之间的平衡。实验结果表明,所提出的解决方案改进了云计算环境的服务质量,并揭示了在云联盟环境中,合作和竞争两种模式的相对优势。展开更多
Multiple QoS modeling and algorithm in grid system is considered. Grid QoS requirements can be formulated as a utility function for each task as a weighted sum of its each dimensional QoS utility functions. Multiple Q...Multiple QoS modeling and algorithm in grid system is considered. Grid QoS requirements can be formulated as a utility function for each task as a weighted sum of its each dimensional QoS utility functions. Multiple QoS constraint resource scheduling optimization in computational grid is distributed to two subproblems： optimization of grid user and grid resource provider. Grid QoS scheduling can be achieved by solving sub problems via an iterative algorithm.展开更多
Packet scheduling algorithm is the key technology to guarantee Quality of Service (QoS) and balance the fairness between users in broadband Wireless Metropolitan Area Network (WMAN). Based on the research of Proportio...Packet scheduling algorithm is the key technology to guarantee Quality of Service (QoS) and balance the fairness between users in broadband Wireless Metropolitan Area Network (WMAN). Based on the research of Proportional Fairness (PF) algorithm and Modified Largest Weighted Delay First (M-LWDF) algorithm, a new packet scheduling algorithm for real-time services in broadband WMAN, called Enhanced M-LWDF (EM-LWDF), was proposed. The algorithm phases in new information to measure the load of service queues and updates the state parameters in real-time way, which remarkably improves system performance.Simulation results show that comparing with M-LWDF algorithm, the proposed algorithm is advantageous in performances of queuing delay and fairness while guaranteeing system throughput.展开更多
The MAC layer in IEEE802.16 is designed to differentiate service among traffic categories with different multimedia requirements.In this paper,a scheduling algorithm at MAC layer for multiple connections with diverse ...The MAC layer in IEEE802.16 is designed to differentiate service among traffic categories with different multimedia requirements.In this paper,a scheduling algorithm at MAC layer for multiple connections with diverse QoS requirements is proposed.As for this algorithm,each connection is assigned a priority,which is updated dynamically based on its service status concluding queue characteristic and channel state.A connection with the highest priority is scheduled each time.Analytical model is developed by assuming a Finite State Markov Chain(FSMC)channel model.Simulation results show that the proposed scheduling algorithm can improve the performance of mean waiting time and throughput in broadband wireless networks.展开更多
针对数据网格环境下的多QoS约束任务调度问题,提出了一种基于最早完成时间与QoS相识度的数据网格任务调度算法(data grid task scheduling algorithm based on Min-min and QoS similarity,MS-GTSA)。该算法将最早完成时间与S-GTSA算法...针对数据网格环境下的多QoS约束任务调度问题,提出了一种基于最早完成时间与QoS相识度的数据网格任务调度算法(data grid task scheduling algorithm based on Min-min and QoS similarity,MS-GTSA)。该算法将最早完成时间与S-GTSA算法相结合,在任务调度过程中,选取任务QoS约束与资源QoS匹配最佳,且完成时间最早的一项优先进行调度。在满足任务最佳QoS匹配的同时,时间跨度得到了较大的改善。仿真结果表明,该算法有效降低了任务调度的时间跨度,在综合性能上较S-GTSA算法有所提高。展开更多
基金Supported by National Key Project of 863 Program of China (No.2002AA122021), Scientific Research Fund of Chongqing Municipal Education Commission (No.040504 and KJ050504), and Chongqing Science and Technology Commission (CSTC, 2005BB2066).
文摘A new scheduling algorithm, which aims to provide proportional and controllable QoS (Quality of Service) in terms of burst loss probability for OBS (Optical Burst Switching) networks, is proposed on the ba- sis of a survey of QoS schemes in current OBS networks. With simulations, performance analysis and com- parisons are carried out in detail. The results show that, in the proposed scheme, burst loss probabilities are proportional to the given factors and the control of QoS performance can be achieved with better performance. This scheme will be beneficial to the OBS network management and the tariff policy making.
基金supported by ZTE Industry-University-Institute Cooperation Funds。
文摘In recent years,various internet architectures,such as Integrated Services(IntServ),Differentiated Services(DiffServ),Time Sensitive Networking(TSN)and Deterministic Networking(DetNet),have been proposed to meet the quality-of-service(QoS)requirements of different network services.Concurrently,network calculus has found widespread application in network modeling and QoS analysis.Network calculus abstracts the details of how nodes or networks process data packets using the concept of service curves.This paper summarizes the service curves for typical scheduling algorithms,including Strict Priority(SP),Round Robin(RR),Cycling Queuing and Forwarding(CQF),Time Aware Shaper(TAS),Credit Based Shaper(CBS),and Asynchronous Traffic Shaper(ATS).It introduces the theory of network calculus and then provides an overview of various scheduling algorithms and their associated service curves.The delay bound analysis for different scheduling algorithms in specific scenarios is also conducted for more insights.
文摘面对国内外大型公有云供应商的激烈竞争,中小云厂商的生存难度加大。为此,建立一个基于相互合作的云联盟成为了这些厂商的一种可行策略。然而,在追求个体最大利益和保障联盟整体服务质量(quality of service,QoS)之间存在着复杂的博弈关系。针对上述问题,一种基于QoS的云联盟模型被提出,其涵盖云计算的三层架构。在应用层至虚拟层,引入了一种基于差分进化(differential evolution,DE)算法的创新任务分配策略,专门用于处理多QoS任务分配问题。在虚拟层至物理层,设计了合作与竞争并存的虚拟机迁移模型,适用于在云联盟博弈计算环境下实现虚拟机迁移的能耗与QoS之间的平衡。实验结果表明,所提出的解决方案改进了云计算环境的服务质量,并揭示了在云联盟环境中,合作和竞争两种模式的相对优势。
基金the National Natural Science Foundation of China (60402028, 60672137) Wuhan Yonger Dawning Foundation (20045006071-15)China Specialized Research Fund for the Doctoral Program of Higher Eduction (20060497015).
文摘Multiple QoS modeling and algorithm in grid system is considered. Grid QoS requirements can be formulated as a utility function for each task as a weighted sum of its each dimensional QoS utility functions. Multiple QoS constraint resource scheduling optimization in computational grid is distributed to two subproblems： optimization of grid user and grid resource provider. Grid QoS scheduling can be achieved by solving sub problems via an iterative algorithm.
基金This work was funded by the National High Technology Research and Development Program ("863" Program) of China under Grant No.2007AA01Z289
文摘Packet scheduling algorithm is the key technology to guarantee Quality of Service (QoS) and balance the fairness between users in broadband Wireless Metropolitan Area Network (WMAN). Based on the research of Proportional Fairness (PF) algorithm and Modified Largest Weighted Delay First (M-LWDF) algorithm, a new packet scheduling algorithm for real-time services in broadband WMAN, called Enhanced M-LWDF (EM-LWDF), was proposed. The algorithm phases in new information to measure the load of service queues and updates the state parameters in real-time way, which remarkably improves system performance.Simulation results show that comparing with M-LWDF algorithm, the proposed algorithm is advantageous in performances of queuing delay and fairness while guaranteeing system throughput.
文摘The MAC layer in IEEE802.16 is designed to differentiate service among traffic categories with different multimedia requirements.In this paper,a scheduling algorithm at MAC layer for multiple connections with diverse QoS requirements is proposed.As for this algorithm,each connection is assigned a priority,which is updated dynamically based on its service status concluding queue characteristic and channel state.A connection with the highest priority is scheduled each time.Analytical model is developed by assuming a Finite State Markov Chain(FSMC)channel model.Simulation results show that the proposed scheduling algorithm can improve the performance of mean waiting time and throughput in broadband wireless networks.
文摘IEEE 802.16作为全球微波接入互操作系统技术标准,虽然定义了5类信流(分别是UGS,rtPS,ertPS,nrtPS和BE),并将服务质量支持机制引入媒体接入控制层,却没有规定相应的调度算法.为有效保证各种多媒体通信的服务质量,提出了一种基于正交频分多址接入技术和自适应调制编码机制的二级调度方案.该调度方案采用跨层设计思想,适用于PMP Wi MAX网络下行链路中.一级调度器按照QoS优先级顺序调度位于不同类型缓存器的队头分组,从而满足rtPS业务的最大时延限定和nrtPS业务的最小速率要求;完成一级调度后,为满足用户速率公平性,二级调度器根据自适应调制编码信息及用户状态信息调度位于不同用户缓存器的队头分组.仿真结果表明该方案能够有效保证各种多媒体通信服务满足QoS要求并兼顾用户速率公平,同时也可获得较高的Wi MAX系统吞吐量.
文摘针对数据网格环境下的多QoS约束任务调度问题,提出了一种基于最早完成时间与QoS相识度的数据网格任务调度算法(data grid task scheduling algorithm based on Min-min and QoS similarity,MS-GTSA)。该算法将最早完成时间与S-GTSA算法相结合,在任务调度过程中,选取任务QoS约束与资源QoS匹配最佳,且完成时间最早的一项优先进行调度。在满足任务最佳QoS匹配的同时,时间跨度得到了较大的改善。仿真结果表明,该算法有效降低了任务调度的时间跨度,在综合性能上较S-GTSA算法有所提高。
