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1.
Programmable agents for flexible QoS management in IP networks   总被引:3,自引:0,他引:3  
Network programmability seems to be a promising solution to network management and quality of service (QoS) control. Software mobile-agents technology is boosting the evolution toward application-level control of network functionalities. Code may be deployed in the network dynamically and on demand for the benefit of applications or application classes. Agents support a dynamic distribution of control and management functions across networks, thus increasing flexibility and efficiency. We propose to use mobile-agent technology to overcome some of the problems inherent in current Internet technology. We focus our attention to QoS monitoring, being locally significant in network subdomains, and realize a QoS management strategy in response to variations of user, customer of application requirements, and of the network state. We describe our experience and the results obtained from our testbed, where software agents are instantiated, executed, migrated, and suspended in order to implement flexible QoS management in IP networks  相似文献   

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3.
Future wireless networks will support the growing demands of heterogeneous and delay sensitive applications. In this paper, a users' satisfaction factor (USF) is defined to quantify quality of service (QoS) for different types of services such as voice, data, and multimedia, as well as for different delay constraints. This USF not only predicts the final delivered QoS during transmission, but also take advantages of the fact that different packets can be decoded at different time in the receivers. Based on this USF, four types of scheduling schemes considering tradeoffs between system performance and individual fairness are proposed. These schemes explore the time, channel, and multi-user diversity to guarantee quality of service and enhance the network performance. From the simulation results, the proposed scheduling schemes achieve different tradeoffs between individual fairness and high system performance for the heterogeneous and delay sensitive applications, compared with the weighted round-robin and the modified proportional fairness scheduling schemes  相似文献   

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5.
移动IP上的QoS保证   总被引:7,自引:0,他引:7  
丰勇  李方伟 《电信科学》2002,18(1):10-12
本文首先分析了基本QoS协议在移动IP上存在的问题并讨论其解决办法 ,在此基础上介绍了一种在移动IP上提供端到端的QoS机制  相似文献   

6.
Today, the policy-based management approach is recognized as an efficient solution to simplify the complex task of managing and controlling networks. To this end, the IETF has introduced a reference framework to build PBM systems. However, this framework only addresses the provisioning of relatively long validity period services based on pre-defined service level agreements. Furthermore, very little work addresses the scalability properties of the instantiation of this framework in a real network. This work aims to extend the IETF PBM framework in order to support dynamic provisioning of short term services (end system signaling) as well as an instantiation scheme that is scalable (distributed provisioning of edge routers). This instantiation scheme is based on the distribution of the provisioning process while keeping centralized only the parts that involve critical resources, that is, the bandwidth brokerage. The performance properties of the proposed scheme are then demonstrated throughout both extensive experimentation and a short analytical study. The results of this work are intended to be used as a guideline to help network operators to design scalable PBM system in order to offer to their customers services with QoS assurance in an on-demand basis.  相似文献   

7.
Policy-based management can guide the behavior of a network or distributed system through high-level declarative directives that are dynamically introduced, checked for consistency, refined, and evaluated, resulting typically in a series of low-level actions. We actually view policies as a means of extending the functionality of management systems dynamically, in conjunction with preexisting hard-wired management logic. We first discuss the policy management aspects of architecture for managing quality of service in IP DiffServ networks as presented by Trimintzios et al. (see IEEE Commun. Mag., Special Issue in IP Operations and Management, vol.39, no.5, p.80-88, 2001), and focus on the functionality of the dimensioning and resource management aspects. We then present an analysis of the policies that can influence the dimensioning behavior as well as the inconsistencies that may be caused by the introduction of such policies. Finally, we describe the design and implementation of the generic policy consumer component and present the current implementation status  相似文献   

8.
This paper describes a signalling environment for Quality of Service (QoS) negotiation and advance resource reservation in mobile IP networks. This environment is built in conformance with the generic signalling environment, which is standardized by the NSIS IETF working group. The advanced resource reservation protocol, called MQoS NSLP, is based on the QoS NSLP signalling application. It provides to mobile terminals the QoS required based on the user's mobility and QoS profile. In this work, we investigate the use of some techniques of the AI (Artificial Intelligence) domain to implement a user interface called NIA (Negotiation Individual Assistant) in order to determine the QoS profile and negotiate the QoS parameters in the new domain after the handover. Therefore, we use connectionist learning in the management of the negotiation profiles and agent technology to help the user choose the best service provider, dynamically negotiate the QoS on the user's behalf, and follow the user's behaviour to be able to anticipate the negotiation and manage renegotiation. The advance resource reservation is based on an object MSpec (Mobility Specification) which determines the future location of the mobile terminal. The MSpec object is a part of the mobility and QoS profile and is determined by the NIA in the mobile terminal. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

9.
随着技术的发展,宽带IP 综合信息网络除提供FTP、HTTP等业务外,越来越多地提供一些多媒体业务,如视频会议、远程教育、远程医疗、VOD点播等,这些业务都有自己的应用系统,与一般业务不同之处在于其对服务质量的要求相对较高,这就要求网络不能仅仅提供简单的连通性,还需提供非常有效的QoS(服务质量保证)机制。QoS是一个比较广泛的概念,它是对各类用户或应用服务水平特征的描述。例如,视频会议一般要求最高的服务等级(first class),数据传输一般要求商业级服务水平(businessclass),Web服务器浏览要求最低,只要满足经济级…  相似文献   

10.
In this paper,an algorithm Wireless Multimedia Transmission Control(WMTC) is proposed for multimedia transmission control over wired-wireless networks.The relationship between packet length and packet loss rate in the Gilbert wireless error model is investigated.Furthermore,the algorithm can detect the nature of packet losses by sending large and small packets alternately,and control the sending rate of nodes.In addition,by means of updating factor K,this algorithm can adapt to the changes of network states...  相似文献   

11.
With information access becoming more and more ubiquitous, there is a need for providing QoS support for communication that spans wired and wireless networks. For the wired side, RSVP/SBM has been widely accepted as a flow reservation scheme in IEEE 802 style LANs. Thus, it would be desirable to investigate the integration of RSVP and a flow reservation scheme in wireless LANs, as an end-to-end solution for QoS guarantee in wired-cum-wireless networks. For this purpose, we propose WRESV, a lightweight RSVP-like flow reservation and admission control scheme for IEEE 802.11 wireless LANs. Using WRESV, wired/wireless integration can be easily implemented by cross-layer interaction at the Access Point. Main components of the integration are RSVP-WRESV parameter mapping and the initiation of new reservation messages, depending on where senders/receivers are located. In addition, to support smooth roaming of mobile users among different basic service sets (BSS), we devise an efficient handoff scheme that considers both the flow rate demand and network resource availability for continuous QoS support. Furthermore, various optimizations for supporting multicast session and QoS re-negotiation are proposed for better performance improvement. Extensive simulation results show that the proposed scheme is promising in enriching the QoS support of multimedia applications in heterogeneous wired-cum-wireless networks. Ming Li received his B.S. and M.S. in Engineering from Shanghai Jiao Tong University, China, in 1995 and 1998, respectively. He is currently a Ph.D. candidate in department of Computer Science, University of Texas at Dallas, where he received M.S. degree in Computer Science in Dec. 2001. His research interest includes QoSschemes for mobile ad-hoc networks and multimedia over wireless networks. Hua Zhu received the Ph.D. degree in Electrical Engineering from the University of Texas at Dallas, Texas. Since 2005, he has been working for San Diego Research Center, Inc., San Diego, CA, as a Research Engineer. His research interests include all layers of wireless communication systems. His particular interest is in L2/3 air interface design, performance analysis, and optimization for ad hoc and sensor networks. Imrich Chlamtac is the President of CREATE-NET and the Bruno Kessler Professor at the University of Trento, Italy. He has held various honorary and chaired professorships in USA and Europe including the Distinguished Chair in Telecommunications Professorship at the University of Texas at Dallas, Sackler Professroship at Tel Aviv University and has been on faculty at Technion, and UMass. Dr. Imrich Chlamtac has made significant contribution to various networking technologies as scientist, educator and entrepreneur. Dr. Chlamtac is the recipient of multiple awards and recognitions including Fellow of the IEEE, Fellow of the ACM, Fulbright Scholar, the ACM Award for Outstanding Contributions to Research on Mobility and the IEEE Award for Outstanding Technical Contributions to Wireless Personal Communications. Dr. Chlamtac published over three hundred and fifty refereed journal, book, and conference articles and is the co-author of four books. Dr. Chlamtac has widely contributed to the scientific community as founder and Chair of ACM Sigmobile, founder and steering committee chair of some of the lead conferences in networking including Mobicom, OptiComm, Mobiquitous, Broadnets, Securecomm. Dr. Chlamtac also serves as the founding Editor in Chief of the ACM/URSI/Springer Wireless Networks (WINET), the ACM/Springer Journal on Special Topics in Mobile Networks and Applications (MONET). B. Prahbakaran is with the faculty of Computer Science Department, University of Texas at Dallas. He has been working in the area of multimedia systems: animation & multimedia databases, authoring & presentation, resource management, and scalable web-based multimedia presentation servers. Dr. Prabhakaran received the prestigious National Science Foundation (NSF) CAREER Award in 2003 for his proposal on Animation Databases. He has published several research papers in various refereed conferences and journals in this area. He has served as guest-editor (special issue on Multimedia Authoring and Presentation) for ACM Multimedia Systems journal. He is also serving on the editorial board of Multimedia Tools and Applications journal, Kluwer Academic Publishers. He has also served as program committee member on several multimedia conferences and workshops. B. Prabhakaran has served as a visiting research faculty with the Department of Computer Science, University of Maryland, College Park. He also served as a faculty in the Department of Computer Science, National University of Singapore as well as in the Indian Institute of Technology, Madras, India.  相似文献   

12.
Next generation networks must be capable of supporting a multitude of service providers that exploit an environment in which services are dynamically deployed and quickly adapted over a common heterogeneous physical infrastructure, according to varying and sometimes conflicting customer requirements. In this context, network management must become more flexible in order to cope with these emerging conditions. More specifically, new management architectures must offer service providers the freedom to manage their services according to their own policies and seamlessly extend management functionality as the only way to react to the introduction of new services. Based on a new business model that describes such an environment, we propose a policy-based management architecture that is extensible and operates in an active and programmable network. This management architecture is part of a new network architecture that was developed in the FAIN European Union research and development IST project.  相似文献   

13.
Traffic management for TCP/IP over satellite ATM networks   总被引:1,自引:0,他引:1  
Several Ka-band satellite systems have been proposed that will use ATM technology to seamlessly transport Internet traffic. The ATM UBR, GFR, and ABR service categories have been designed for data. However, several studies have reported poor TCP performance over satellite ATM networks. We describe techniques to improve TCP performance over satellite ATM networks. We first discuss the various design options available for TCP end systems, IP-ATM edge devices, as well as ATM switches for long-latency connections. We discuss buffer management policies, guaranteed rate services, and the virtual source/virtual destination option in ATM. We present a comparison of ATM service categories for TCP transport over satellite links. The main goal of this article is to discuss design and performance issues for the transport of TCP over UBR, GFR, and ABR services for satellite ATM networks  相似文献   

14.
Self‐aware management allows the network to react and to adapt to changes of situation. In this paper an architecture is described for self‐aware management of IP networks offering QoS guarantees. This architecture uses policy‐based management and multi‐agent systems. The originality of the present approach lies in the intention to give a real autonomy to the components intervening in the chain of services in terms of internal decisions and configuration. Our solution allows the self‐configuration, self‐provisioning and self‐monitoring of service as well as the proactive service level agreement management. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

15.
In this article, we consider traffic grooming and integrated routing in IP over WDM networks. The challenges of this problem come from jointly considering traffic grooming, IP routing, and lightpath routing and wavelength assignment (RWA). Due to the high bandwidth of optical fiber, there exists a mismatch between the capacity needed by an IP flow and that provided by a single lightpath. Traffic grooming is therefore used to increase the network utilization by aggregating multiple IP flows in a single lightpath. However, traffic grooming incurs additional delays that might violate Quality-of-Service (QoS) requirements of IP users. In this work, the tradeoff between traffic grooming and IP QoS routing is well-formulated as a mixed integer and linear optimization problem, in which the revenue from successfully provisioning IP paths is to be maximized. Problem constraints include IP QoS, routing, optical RWA, and the WDM network capacity. We propose a novel Lagrangean relaxation (LGR) algorithm to perform constraint relaxation and derive a set of subproblems. The Lagrangean multipliers are used in the proposed algorithm to obtain a solution in consideration of grooming advantage and resource constraints simultaneously. Through numerical experiments and comparisons between the proposed algorithm and a two-phase approach, LGR outperforms the two-phase approach under all experimental cases. In particular, the improvement ratio becomes even more significant when the ratio of IP flow to the wavelength capacity is smaller.  相似文献   

16.
Mobility management applied to the traditional architecture of the Internet has become a great challenge because of the exponential growth in the number of devices that can connect to the network. This article proposes a Software‐Defined Networking (SDN)‐based architecture, called SDN‐DMM (SDN‐Distributed Mobility Management), that deals with the distributed mode of mobility management in heterogeneous access networks in a simplified and efficient way, ensuring mainly the continuity of IP sessions. Intent‐based mobility management with an IP mapping schema for mobile node identification offers optimized routing without tunneling techniques, hence, an efficient use of the network infrastructure. The simplified mobility control API reduces both signaling and handover latency costs and provides a better scalability and performance in comparison with traditional and SDN‐based DMM approaches. An analytical evaluation of such costs demonstrated the better performance of SDN‐DMM, and a proof of concept of the proposal was implemented in a real environment.  相似文献   

17.
本文分析了IP网络QoS(Quality of Service)管理中的资源管理机制,并在此基础上提出了基于网络状态监测的反馈控制方法和3个反馈环路.通过对网络历史状态信息的采集分析,定期重新分配瓶颈链路的带宽和各链路流量类的带宽,可以提高业务的接纳率和网络的业务容量.该方法实现在一个基于CORBA的原型系统中.  相似文献   

18.
End-to-end QoS provisioning in mobile heterogeneous networks   总被引:3,自引:0,他引:3  
The remarkable advances in information technologies bring a heterogeneous environment for mobile users and service providers. This heterogeneity exists in wireless access technologies, networks, user terminals, applications, service providers, and so on. The ability to provide seamless and adaptive quality of service in such a heterogeneous environment is key to the success of next-generation wireless communications systems. There has been a considerable amount of QoS research recently. However, the main part of this research has been in the context of individual architectural components, and much less progress has been made in addressing the issue of an overall QoS architecture for the mobile Internet. This article first summarizes the state-of-the-art QoS techniques and standardization activities, then examines in detail important challenges in building a ubiquitous QoS framework over the heterogeneous environment, and finally proposes a QoS framework integrating a three-plane network infrastructure and a unified terminal cross-layer adaptation platform to provide seamless support for future applications.  相似文献   

19.
IP over WDM网中的策略路由算法   总被引:2,自引:0,他引:2  
业务量工程允许管理者通过赋予业务主干不同的业务量工程属性来体现一定的管理策略,在为业务主干建立标记交换路径(LSP)时也应该考虑这些策略的影响,该文讨论了业务主干具有不同优先权属性时的 LSP建立问题,针对中断 LSP个数最少和中断业务量最小两种指标,分别提出不同的解决策略:最小连接数中断法(MCNIM)和最小连接带宽中断法(MCBIM),并在不同负载的动态业务下对所提算法进行了仿真研究,给出了仿真结果。  相似文献   

20.
Active distributed management for IP networks   总被引:19,自引:0,他引:19  
We argue that a management platform for the future Internet has to be inherently distributed and programmable. This motivates us to introduce a new management architecture, named active distributed management, which exploits the active network and mobile agent paradigms and provides the properties of distributed control and programmability inside the network. We realize the ADM architecture as a management middleware composed of several layers. In order to facilitate the development of efficient and correct programs, these layers include patterns for distributed algorithms that are typical for management applications and a set of building blocks for constructing management programs. First results of an ADM prototype system are presented  相似文献   

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