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qos Guided Min—Min Heuristic for Grid Task Scheduling

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Journal of Computer Science & Technology 2003年第4期18卷 442-451页

作者：何晓珊孙贤和 Gregor von Laszewski Department of Computer Science Illinois Institute of Technology IL USA Mathematics and Computer Science Division Argonne National Laboratory IL USA

Task scheduling is an integrated component of computing. With the emergence of Grid and ubiquitous computing, new challenges appear in task scheduling based on properties such as security, quality of service, and lack of central control within distributed administrative domains. A Grid task scheduling framework must be able to deal with these issues. One of the goals of Grid task scheduling is to achieve high system throughput while matching applications with the available computing resources. This matching of resources in a non-deterministically shared heterogeneous environment leads to concerns over Quality of Service (qos). In this paper a novel qos guided task scheduling algorithm for Grid computing is introduced. The proposed novel algorithm is based on a general adaptive scheduling heuristics that includes qos *** algorithm is evaluated within a simulated Grid environment. The experimental results show that the new qos guided Min-Min heuristic can lead to significant performance gain for a variety of applications. The approach is compared with others based on the quality of the prediction formulated by inaccurate information.

关键词： qos 任务调度网格计算服务质量非贡献计算

Parallel Switch System with qos Guarantee for Real-Time Traffic

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Journal of Computer Science & Technology 2006年第6期21卷 1012-1021页

作者：李文杰刘斌徐扬廖恒 Department of Computer Science and Technology Tsinghua University Beijing 100084 P.R. China PMC-SIERRA 8555 Baxter Place Burnaby BC V5A4V7 Canada

This paper studies the load-balancing algorithm and quality of service （qos） control mechanism in a 320Gb/s switch system, which incorporates four packet-level parallel switch planes. Eight priorities for both unicast and multicast traffic are implemented, and the highest priority with strict qos guarantee is designed for real-time traffic. Through performance analysis under multi-prlorlty burst traffic, we demonstrate that the load-balancing algorithm is efficient, and the switch system not only provides excellent performance to real-time traffic, but also efficiently allocates bandwidth among other traffic of lower priorities. As a result, this parallel switch system is more scalable towards next generation core routers with qos guarantee, as well as ensures in-order delivery of IP packets.

关键词： load-balancing parallel priority qos switch system

Web Service Composition Based on qos Rules

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Journal of Computer Science & Technology 2010年第6期25卷 1143-1156页

作者：张明卫张斌刘莹那俊朱志良 College of Software Northeastern University College of Information Science and Engineering Northeastern University

For workflow-based service composition approach,the relations between the Web service qos and environments are usually not considered,so that the information about qos for composite service selection is *** makes the selected composite service inefficient,or even *** address this problem,a novel service composition approach based on production qos rules is proposed in this ***,it is very difficult to directly analyze how different kinds of environment factors influence the Web service *** adopt ＂black-box＂ analysis method of optimizing composite services,discovering the knowledge such as ＂the qos of one Web service will be higher in specific environments＂.In our approach,the execution information of the composite service is recorded into a log first,which will be taken as the basis of the subsequent statistical analysis and data ***,the timely qos values of the Web services are estimated and the production qos rules being used to qualitatively express the different performances of the Web service qos in different environments are *** last,we employ the mined qos knowledge of the Web services to optimize the composite service *** experimental results show that our approach can improve the performance of selected composite services on the premise of assuring the selecting computation cost.

关键词： service composition service selection qos data mining production rules

An End-to-End qos Control Model for Enhanced Internet

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Journal of Computer Science & Technology 2000年第6期15卷 497-508页

作者：张尧学王晓春顾钧 DepartmentofComputerScienceandTechnology TsinghuaUniversityBeijing100084P.R.China

This paper describes an end-to-end qos (Quality of Services) control model for distributed multimedia computing on enhanced Internet, and gives the design and implementation of this model including hosts and routers. The architec- ture, the mathematical definition about qos parameters, and the mapping between Integrated Service (IS) and Differentiated Service (DS) are discussed in this paper. The simulation shows that this model can improve the performance of audio streams when it is used in IPhone system.

关键词： protocol multimedia networking qos RSVP (Resource ReSerVation Protocol) router

An Effective Randomized qos Routing Algorithm on Networks with Inaccurate Parameters

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Journal of Computer Science & Technology 2002年第1期17卷 38-46页

作者：王建新陈建二陈松乔 Department of Computer Science Central South University Changsha 410083 P.R. China

This paper develops an effective randomized on-demand qos routing algorithm on networks with inaccurate link-state information. Several new techniques are proposed in the algorithm. First, the maximum safety rate and the minimum delay for each node in the network are pre-computed, which simplify the network complexity and provide the routing process with useful information. The routing process is dynamically directed by the safety rate and delay of the partial routing path developed so far and by the maximum safety rate and the minimum delay of the next node. Randomness is used at the link level and depends dynamically on the routing configuration. This provides great flexibility for the routing process, prevents the routing process from overusing certain fixed routing paths, and adequately balances the safety rate and delay of the routing path. A network testing environment has been established and five parameters are introduced to measure the performance of qos routing *** results demonstrate that in terms of the proposed parameters, the algorithm outperforms existing qos algorithms appearing in the literature.

关键词： qos network routing randomized algorithm link-state information performance measure

qos-aware multicast routing protocol for Ad hoc networks

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Journal of Systems Engineering and Electronics 2006年第2期17卷 417-422页

作者： Sun Baolin Li Layuan School of Computer Science and Technology Wuhan Univ. of Technology Wuhan 430063. P. R. China Dept. of Mathematics and Physics Wuhan Univ. of Science and Engineering Wuhan 430073. P. R. China

Ad hoe wireless networks consist of mobile nodes interconnected by multihop communication paths. Unlike conventional wireless networks, ad hoc networks have no fixed network infrastructure or administrative support. Due to bandwidth constraint and dynamic topology of mobile ad hoc networks, supporting Quality of Service （qos） is an inherently complex, difficult issue and very important research issue. MAODV （Multicast Ad hoc Ondemand Distance Vector） routing protocol provides fast and efficient route establishment between mobile nodes that need to communicate with each other. MAODV has minimal control overhead and route acquisition latency. In addition to unicast routing, MAODV supports multicast and broadcast as well. The multicast routing problem with multiple qos constraints, which may deal with the delay, bandwidth and packet loss measurements is discussed, and a network model for researching the ad hoc network qos multicast routing problem is described. It presents a complete solution for qos multicast routing based on an extension of the MAODV routing protocol that deals with delay, bandwidth and packet loss mesurements. The solution is based on lower layer specifics. Simulation results show that, with the proposed qos multicast routing protocol, end-to-end delay, bandwidth and packet loss on a route can be improved in most of cases. It is an available approach to multicast routing decision with multiple qos constraints.

关键词： multieast routing routing protocol qos AODV MAODV.

Performance analysis of IP qos provision model

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通信学报 2006年第Z1期27卷 208-213页

作者： SUN Danning Moonsik Kang Information and Electronic Engineering School Shandong Institute of Business and Technology Yantai 264005 China KangNung National University South Korea

The Performance of a heterogeneous IP qos provision service model was analyzed. This model utilized RSVP technique to set up dynamic resource reservation interface between the user and the network, meanwhile, DiffServ technique was utilized to transmit class-based packets in different per hop behaviors. Furthermore, accordingly queue management and packets scheduling mechanisms were presented for end-to-end qos guarantees and appropriate cooperation of network elements.

关键词： Diffserv Intserv qos RSV

An Analytical Framework for Performance of Different Fault Restoration Policies with qos Constraints in MPLS Networks

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Journal of Computer Science & Technology 2004年第2期19卷 158-168页

作者： Xian-SiTan Zong-KaiYang LiangOu Jing-WenChen Ya-JieMa DepartmentofElectronicsandInformation HuazhongUniversityofScienceandTechnologyWuhan430074P.R.China

An analytical framework for the performance of different protection switching restoration mechanisms with different protection policies in Multi-Protocol Label Switching (MPLS) networks is developed, where the protection policy may be 1 + 1, 1:1, n:1 or n:m. As a general rule, it aims at the MPLS networks with the protection paths created in advance of fault occurrence without resources reserved, and it reroutes the protected traffic in the event of link or router failures while trying to maintain quality of service (qos) requirements. Based on the proposed protocol for processing faults, an analytical model and an evaluating model are created, and the benefits and penalties of different mechanisms with different protection policies are evaluated. In particular, an improvement on the proposed protocol is presented to overcome the drawbacks of n:m protection policy in which m > 1 and n > 1.

关键词： MPLS fault restoration qos analytical framework restoration policy

Distributed Coordinator Election Scheme for qos Support and Seamless Connectivity in WPANs

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Journal of Computer Science & Technology 2009年第6期24卷 1138-1148页

作者： Soon-Gyu Jeong Sang-Jo Yoo Graduate School of Information Technology & Telecommunications Inha University

Wireless personal area networks （WPANs） are formed in a relatively small area, and coordinator that serves as a central control device plays an important role in the operation and organization of a piconet. Typical applications of WPANs include home automation systems, security systems and health monitoring systems. In these types of systems, guaranteeing seamless connectivity is very important, and communications cannot take place when the coordinator malfunctions. Thus, in the case of a breakdown, it is necessary to elect a new coordinator as soon as possible. For this reason, a distributed coordinator election scheme （DCES） is proposed that considers not only qos support but also network connectivity in an effort to avoid possible network partition. Simulation results show that the proposed scheme can elect a new coordinator while maintaining qos and guaranteeing connectivity for a limited period.

关键词： qos seamless connectivity leader election piconet coordinator (PNC) wireless personal area network (WPAN)