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1.
多维过滤规则无冲突的高速分组分类算法   总被引:3,自引:1,他引:2       下载免费PDF全文
杜德超  姚庆栋 《电子学报》2002,30(11):1676-1680
为了有效地实现防火墙及QoS路由等功能,路由器等网络元素必须能高速地对分组分类.对一维分组分类,已有很多成熟方案,而多维算法由于实现复杂,还没有有效的分类算法.本文对无过滤规则无冲突的数据库进行了研究,提出了基于元组空间多维分组分类算法:元组空间矢量位映射算法.对多维和二维分类在最不利情况下分别进行了性能分析,指出与已有的方案相比,在存贮空间、查找时间等性能上,本文提出的算法是效率最佳的.本文的算法不仅可以由软件实现,也很容易由硬件实现.  相似文献   

2.
简单数据链路协议(SDL)作为一种新型的IP over技术,其简单性和低开销更能适应高速传输链路的要求,并提供下一代光分组交换网所需要的操作维护管理功能,如何提供服务质量保证(QoS)是IP传输中的核心技术之一,文章介绍了IETF提出的两种实现QoS的业务模型;集成业务模型和差分业务模型,以及SDL;提出了一种基于SDL链路协议上的Diffserv over MPLS的QoS实现方案。  相似文献   

3.
杨炼  彭涛 《电视技术》2012,36(23):87-90,115
为了提供用户差异化服务体验,更好地保证端到端的QoS机制,EPS系统支持通过EPS承载对分组数据进行传送,有效地实现QoS参数之间的映射。通过对业务流模板(TFT)的研究,针对移动终端软件实现上行IP分组包与数据无线承载(DRB)的绑定过程中,存在影响终端速率和耗占系统资源的弊端,提出TFT功能硬化方案,提高IP分组包与UL_PF匹配速率,减少IP分组包与EPS承载的绑定及处理时间,最终实现IP数据在EPS承载上传输。  相似文献   

4.
为了更好保证端到端的QoS机制,为用户提供差异化服务体验,EPS系统支持通过EPS承载对分组数据进行传送。本文通过对业务流模块(TFT)的研究,了解UE中上行分组过滤器(UL_PF)与EPS承载的关系,研究上行IP分组包与分组过滤器(PF)的匹配过程,给出一种PF与IP分组包之间的匹配实现方案,最终实现IP数组在EPS承载上传输。  相似文献   

5.
分布式服务质量路由预计算算法   总被引:1,自引:0,他引:1       下载免费PDF全文
崔勇  吴建平 《电子学报》2005,33(12):2165-2169
服务质量路由作为下一代IP互联网提供服务质量(QoS)控制的一种重要方案,如何提高其可扩展性和路由性能是有待解决的难题.本文提出了基于聚类的分布式预计算算法,以具有多种QoS参数的路由表预计算为目标,引入了支持QoS参数的扩展距离向量,通过网络中各个节点的分布式协同计算,大大降低了单个路由器的计算复杂度.文章分析了优势路径及其选取策略,给出了路由计算中优势路径聚集的聚类方法,实现了QoS路由表的高效聚集压缩.实验结果进一步验证了该算法具有计算量小和QoS路由性能高的优点,在QoS度量维数和网络规模方面均具有良好的可扩展性,并对域间算法研究提供了重要依据.  相似文献   

6.
WCDMA IP多媒体子系统中基于策略的QoS管理   总被引:2,自引:0,他引:2  
WCDMA可为用户提供高速的多媒体业务,为了能够更好地提供多媒体业务,3GPP标准化组织自R5版起在分组域上添加了IP多媒体子系统,利用IP多媒体子系统提供端到端的、有QoS保证的、基于IP的多媒体应用服务,其核心部分就是基于策略的QoS控制管理.本文将详细介绍IP多媒体子系统中基于策略的QoS管理体系结构,以及它是如何实现QoS保证的.  相似文献   

7.
EPS系统中业务流模板研究   总被引:2,自引:1,他引:1  
为了更好地保证端到端的QoS机制,为用户提供差异化服务体验,EPS系统支持通过EPS承载对分组数据进行传送。通过对业务流模板(TFT)的研究,了解UE中上行分组过滤器(UL_PF)与EPS承载的关系,研究上行IP分组包与分组过滤器(PF)的匹配过程,给出一种PF与IP分组包之间的匹配实现方案,最终实现IP数组在EPS承载上传输。  相似文献   

8.
一种基于MPLS VPN的QoS路由机制   总被引:1,自引:0,他引:1  
蔡慧  韩国栋  刘洪波  陈魏鑫 《通信技术》2007,40(11):244-246
文中提出一种基于MPLSVPN的QoS路由机制,通过隧道穿越IP骨干网连接MPLS站点,实现MPLSVPN的QoS路由,查找满足最低代价、最高带宽的链路,在更好地满足VPN中的各种业务对服务质量要求的同时,通过合理调配网络资源,提高了网络资源利用率,实现了可靠高效的QoS路由.  相似文献   

9.
提出了一种新的光突发装配技术,目的在于增强光突发交换(OBS)网络的服务质量(QoS)能力。该技术由自适应门限突发装配算法和基于优先级的随机化的偏移时间设置方案构成。该装配算法特别适合于多类别分组混合装配,能让所有类别的分组公平有效地使用装配能力,能较好地与IP层的QoS机制相匹配。偏移设置方案将突发控制分组(BCP)与突发数据(BP)间的偏移时间分成QoS偏移和随机偏移,前者由改进的JET协议按照有选择性的突发段丢弃机制(BSSD)确定,后者则由令牌桶机制确定。BSSD仅丢弃包含有低类别分组的突发段,而非整个突发。计算机仿真结果表明,本文提出的突发装配技术在性能上具有优越性。  相似文献   

10.
随着IP网络的发展,IP网络的服务质量(QoS,Quality of Service)日益成为人们关注的主要问题,本文着重分析了分组交换网络的QoS特点及实现QoS保证的一般方法.  相似文献   

11.
为了提高无线自组网的容量,满足多媒体任务的服务质量(QoS)要求,该文引入多无线收发器技术,扩展单接口单信道下的无状态QoS模型SWAN为多接口多信道下的无状态QoS模型MMSWAN。同时,提出一种多接口多信道下的QoS路由协议MMQAODV,通过与MMSWAN的结合,实现了一种跨层的QoS保障机制。模拟试验表明,这种机制有效地提高了多媒体任务的QoS和尽力而为任务的性能,与SWAN相比延迟减少为它的2%~27%左右,提交的尽力而为数据量为它的1.29~3.55倍。  相似文献   

12.
邵志伟  浦小祥 《信息技术》2007,31(12):41-43
Internet网络规模的迅速增长和网络技术的不断完善,使得如何在满足QoS(quality of service)要求下进行路由选择成为路由算法研究的重要方向。提出了一种多约束条件下的自适应蚁群算法,该算法基于目标函数的信息素分配策略来自适应地调整蚂蚁的搜索行为,使多约束QoS路由优化问题得到了很好的解决。  相似文献   

13.
Novel routing paradigms based on policies, quality of service (QoS) requirements, and packet content have been proposed for the Internet over the last decade. Constraint-based routing algorithms select a routing path satisfying constraints that are either administrative-oriented (policy routing) or service-oriented (QoS routing). The routes, in addition to satisfying constraints, are selected to reduce costs, balance network load, or increase security. In this article, we discuss several constraint-based routing approaches and explain their requirements, complexity, and recent research proposals. In addition, we illustrate how these approaches can be integrated with Internet label switching and QoS architectures. We also discuss examples of application-level routing techniques used in today's Internet.  相似文献   

14.
The IETF developed two main approaches to provide QoS aware services in the Internet: Integrated Services (IntServ) and Differentiated Services (DiffServ). Both have well known pros and cons (e.g., [Huston, 24; Bernet et al., 2]). The stateful IntServ has a greater level of accuracy and a finer level of granularity. The stateless DiffServ possesses excellent scaling properties, but lacks a standardized admission control scheme and, upon overload in a given service class, degradation of service can occur. To provide QoS in DiffServ, three possible strategies are: (i) plain and heavy over-dimensioning; (ii) admission control at the borders of the DiffServ region, coupled with suitable assumptions on the distribution of the traffic within the region, which can lead to over-dimensioning, even if less severe than the previous one; (iii) per-node admission control within the region. Following RFC2990, we recently proposed an “admission control function which can determine whether to admit a service differentiated flow along the nominated network path” [Huston, 24], i.e., the third of the above strategies. This function, named GRIP (Gauge and Gate Reservation with Independent Probing), can provide strict QoS guarantees by means of stateless DiffServ-compliant procedures. This feature is paid with a potential loss of efficiency, with respect to an ideal, stateful admission control. The goal of this paper is to evaluate analytically such loss of efficiency, in a specific heterogeneous scenario. In other words, we want to estimate how much resources we can waste if we go stateless and avoid state maintenance functions. The comparison between stateless and stateful approaches is performed under the constraint of strictly offering the same performance levels, in terms of, e.g., loss probability and delay.  相似文献   

15.

Vehicular ad hoc networks known by their greatly active topology have given rise to new challenges related to routing protocols, issues of less concern in infrastructure-based networks or even in mobile ad hoc networks. Indeed, the high revocability of network topology makes the satisfaction of driver’s requirements very arduous, especially with multimedia applications that need strict quality of service (QoS) support. The main purpose of this paper is to promote real time video traffic by maximizing user gratification while keeping a good QoS. Thus, based on the well-known greedy perimeter stateless routing (GPSR) protocol, we propose a new approach called fuzzy geographical routing (FzGR) that incorporates two fuzzy logic usages. The first takes into consideration three input parameters of QoS: the delay, the size of buffer and the throughput, while it outputs a single relevant metric to prioritize the next-hop with lower concern. The other fuzzy system aims at preserving the concept of basic GPSR by considering the distance measure between each next-hop and the final destination. The proposal has been evaluated and compared to the GPSR using a rigorous metrics analysis regarding QoS and quality of experience. Our extensive experimental results using several simulators (e.g., NS-2, VanetMobiSim and Evalvid), show that FzGR has the ability to increase the performance of the network.

  相似文献   

16.
A scalable framework for in IP-oriented terrestrial-GEO satellite networks   总被引:1,自引:0,他引:1  
The exponential growth of the Internet, the heterogeneity of networks, and the need for QoS maintenance have urged researchers to develop ideas for managing network scalability and end-to-end QoS assurance. In this article, an IP IntServ architecture in the satellite access network is combined with a scalable IP DiffServ-like architecture in the terrestrial core network. The proposed architecture aims at guaranteeing fine-grained bandwidth control in the satellite access network and stateless scalability in the core network, by exploiting per-aggregate traffic flow control, typical of the aggregate RSVP protocol, and stateless service assurance, typical of the SCORE approach.  相似文献   

17.
随着Internet网络的不断发展,它将成为未来网络服务的平台,而未来网络服务的种类又是多种多样的,既有传统的尽量服务(Best-Effort Service)应用,又有对网络服务质量 [1](QoS:Quality of Service)有着特殊需求的应用.本文探讨了如何在网络层路由这一层面进行QoS组播路由支持的问题.目前,已有许多组播QoS路由算法提出,在QoS路由性能、网络资源使用效率以及路由吞吐率等方面取得了许多好的成果.针对这些QoS路由算法中存在的一些问题,提出了一种组播QoS路由算法.实验结果表明:该算法在适应网络拓扑结构、网络规模、对称/非对称链路负载等方面,与其它QoS路由算法相比,在算法性能上有了一定的改进.  相似文献   

18.
In this paper, we propose a new quality-of-service (QoS) routing protocol for mobile ad hoc network (MANET) using directional antennas. The proposed scheme offers a bandwidth-based routing protocol for QoS support in MANET using the concept of multi-path. Our MAC sub-layer adopts the CDMA-over-TDMA channel model. The on-demand QoS routing protocol calculates the end-to-end bandwidth and allocates bandwidth from the source node to the destination node. The paths are combined with multiple cross links, called shoelace, when the network bandwidth is strictly limited. Due to the property of the directional antenna, these cross links can transmit data simultaneously without any data interference. We develop a shoelace-based on-demand QoS routing protocol by identifying shoelaces in a MANET so as to construct a QoS route, which satisfied the bandwidth requirement, more easily. The shoelace-based route from the source to the destination is a route whose sub-path is constructed by shoelace structure. With the identified shoelaces, our shoelace-based scheme offers a higher success rate to construct a QoS route. Finally, simulation results demonstrate that the proposed routing protocol outperform existing QoS routing protocols in terms of success rate, throughput, and average latency.  相似文献   

19.
高效率的小规模Ad Hoc组播路由协议   总被引:1,自引:1,他引:0  
Ad Hoc网络中,组播路由协议具有广泛的应用前景。但由于网络拓扑的变化和节点能量的限制,设计具有高效传输能力的组播路由协议比较困难。通过综合比较表驱动路由协议与按需路由协议的优缺点,并且考虑Ad Hoc网络中节点的移动性以及路由发现与路由维护的方法对传输效率的影响,在无状态组播路由的基础上,使用表驱动与按需路由驱动相结合的路由方法,提出一种新的组播路由协议,使传输效率有较高的提升。  相似文献   

20.
Energy efficiency and quality of service (QoS) are both essential issues in the applications of wireless sensor networks (WSNs) all along, which are mainly reflected in the development of routing and MAC protocols. However, there is little design for achieving the dual performances simultaneously. In this paper, we develop a practical passive cluster-based node-disjoint many to one multipath routing protocol to satisfy the requirements of energy efficiency and QoS in practical WSNs. Passive clustering approach is put to use in the first round, while active clustering technique is taken in the other rounds. Implementation of smart delay strategy makes the cluster distribute uniformly, as well as lessen the number of nodes that have taken part in routing. Among cluster heads, a node-disjoint many to one multipath routing discovery algorithm, which is composed of the optimal path searching process and multipath expansion process, is implemented to find multiple paths at the minimum cost. The simulation results show the proposed protocol achieved very good performance both in energy efficiency and QoS.  相似文献   

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