具有不确定信息的QOS路由的选择与分析

为了减少不确定信息对QoS(服务质量)路由的选择产生的影响，因此有必要对具有不确定信息的QoS路由问题进行研究，讨论了网络状态的不确定信息产生的原因，并基于NS(网络仿真)软件，仿真分析了不确定信息对QoS路由和网络性能的影响，然后，结合QoS单播路由问题，通过对有关问题的形式化描述，讨论了相关的解决方案，最后，综合目前相关解决方案存在的优缺点，从实现的角度探讨了以延迟保证为约束条件的多路径QoS路由机制。     

基于OPNET仿真的QoS路由协议的研究与改进

Ad Hoc无线网络在商业和军事上应用广泛,保障多媒体业务传输质量成为Ad Hoc网络研究的重点;提出了改进的QoS路由技术,D-QoSR,该技术的主要特点是在QoS路由中加入约束条件,预测网络的延迟情况,以便提前修改路由;基于OPNET工具实现D-QoSR和DSR协议的仿真,比较了两种协议的延迟、投递率、路由开销等性能,结果显示D-QoSR减轻了网络延迟,提高了网络性能。     

移动Ad Hoc网络中QoS参数的相关性研究

QoS参数的相关性研究对多约束条件下的QoS路由优化具有重要意义.本文结合仿真和理论分析,研究了移动ad hoc网络中三个重要的QoS参数——业务流的带宽、分组平均延迟、延迟抖动——的相关性问题,得到了这些参数间关系的解析表达式来.通过进一步的仿真验证,结果表明所得到的关系与试验结果相吻合.     

基于分级结构的优化QoS路由算法

Ad hoc(自组织)网络中包含延迟、延迟抖动、带宽和丢包率等约束条件在内的QoS(服务质量)路由问题,是一个NP完全问题,传统的平面QoS蚂蚁路由算法难以解决提高算法全局搜索能力和加快收敛速度之间的矛盾。针对以上问题,提出了HQAC(分级QoS蚁群)算法,在分级的基础上对蚁群算法的路由搜寻过程进行了改进,同时对信息素更新公式进行了优化。仿真结果表明,与传统的QoS路由算法相比,HQAC算法在搜索全局最优解,尤其是收敛速度等性能上有了很大的提高。     

基于分级结构的优化QoS路由算法北大核心

Ad hoc(自组织)网络中包含延迟、延迟抖动、带宽和丢包率等约束条件在内的QoS(服务质量)路由问题,是一个NP完全问题,传统的平面QoS蚂蚁路由算法难以解决提高算法全局搜索能力和加快收敛速度之间的矛盾。针对以上问题,提出了HQAC(分级QoS蚁群)算法,在分级的基础上对蚁群算法的路由搜寻过程进行了改进,同时对信息素更新公式进行了优化。仿真结果表明,与传统的QoS路由算法相比,HQAC算法在搜索全局最优解,尤其是收敛速度等性能上有了很大的提高。     

QoS路由中若干问题的研究

随着网络多媒体应用技术的发展,局域网和广域网实时传输视频和音频信息正成为非常重要的应用,具有确定服务质量(QoS)保证的网络提供变得日益重要。QoS路由为具有不同QoS要求的应用寻求符合条件的网络传输路径,一般来说,它要能满足用户的QoS请求和优化网络资源利用率两个主要目标。QoS路由是实现网络支持QoS的核心技术之一,也是当前网络技术领域的一个研究热点。文中简述QoS路由的定义,讨论QoS路由的基本概念和问题,并分析尚待解决的若干问题。     

一种基于多目标优化的Ad Hoc网络QoS路由算法

目前的一些Ad hoc网络QoS路由算法难以满足军事系统中一些特定业务对于多个目标的同时要求,本文选取带宽作为约束条件,把时延和丢失率作为QoS优化目标,建立了QoS路由选择的多目标整数优化模型,并给出了求解模型的算法.实例计算结果表明了算法的可行性.     

模糊QoS路由算法及其性能分析

我们将模糊理论引入QoS路由领域中,提出了模糊QoS路由算法,在只增加相对较少的计算开销的基础上,有效地提高了QoS路由在离网络负载下的路由成功率和对链路信息滞后性的适应性。     

非确定环境下的QoS网络路由问题

该文探讨非确定环境下的QoS路由问题,包括最大可能性路径,最优路径分解以及最优分解路径问题。本文分析了当链路延迟为连续变量时最大可能性路径问题的求解,给出了链路延迟为正态分布时的相关算法。对于最优路径分解以及最优分解路径问题,本文给出了两种QoS分解方式:方式Ⅰ优化路径各链路满足QoS需求的可能性的乘积,方式Ⅱ优化路径各链路满足QoS需求的可能性的最小值。该文对其分别进行分析并给出具体算法。     

基于性能定价下的最优QoS路由研究

网络运营商在提供QoS服务时,往往根据服务的等级来确定资费.在基于性能的定价下,最优QoS路由的优化问题为最优QoS划分与路由(OPQR)问题.用K条最短路径来代替全部路径,从而将OPQR问题转化为最优QoS划分问题,并提出了求解OPQR问题的混合遗传算法.仿真结果表明了该算法的有效性.     

Delay constraint multipath routing for wireless multimedia ad hoc networks

According to the disadvantages of real time and continuity for multimedia services in ad hoc networks, a delay constraint multipath routing protocol for wireless multimedia ad hoc networks, which can satisfy quality of service (QoS) requirement (QoS multipath optimized link state routing [MOLSR]), is proposed. The protocol firstly detects and analyzes the link delay among the nodes and collects the delay information as the routing metric by HELLO message and topology control message. Then, through using the improved multipath Dijkstra algorithm for path selection, the protocol can gain the minimum delay path from the source node to the other nodes. Finally, when the route is launched, several node‐disjoint or link‐disjoint multipaths will be built through the route computation. The simulation and test results show that QoS‐MOLSR is suitable for large and dense networks with heavy traffic. It can improve the real time and reliability for multimedia transmission in wireless multimedia ad hoc networks. The average end‐to‐end delay of QoS‐MOLSR is four times less than the optimized link state routing. Copyright © 2014 John Wiley & Sons, Ltd.     

Constraint-based routing in the internet: Basic principles and recent research

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.     

Hadoop平台下一种改进蚂蚁算法的QoS路由研究

随着未来云计算的发展,各种云服务的应用将需要更高的网络性能。链路拥塞导致的数据包传输时延或数据包丢弃使得网络无法保障业务的QoS。目前普遍使用的链路状态路由算法不具有拥塞响应机制。本文通过在拥塞节点间发送连接蚂蚁寻找新路由来解决拥塞问题。NS2仿真结果表明,该算法能加快新的路由搜索,满足QoS的需求,并有效控制丢包率,时延等性能。     

Advertising interdomain QoS routing information

To enable end-to-end quality-of-service (QoS) guarantees in the Internet, based on the border gateway protocol (BGP), interdomain QoS information advertising, and routing are important. However, little research has been done in this area so far. Two major challenges, scalability and heterogeneity, make the QoS extension to BGP difficult. In the existing routing schemes, static and instantaneous QoS metrics, such as link capacity and available bandwidth, are used to represent QoS routing information, but neither of them can solve the two challenges well. In this paper, BGP is extended to advertise available bandwidth and delay information of routes, but, instead of using the traditional deterministic metrics, a series of statistical metrics, available bandwidth index (ABI), delay index (DI), available bandwidth histogram (ABH), and delay histogram (DH), are defined and applied to QoS information advertising and routing. Two major contributions of the proposed statistical metrics are: 1) QoS information is abstracted into one or several probability intervals and, thus, the heterogeneous and dynamic QoS information can be represented more flexibly and precisely and 2) by capturing the statistical property of the detailed distribution of QoS information, these new metrics are efficient and they can highly decrease the message overhead in routing, thereby making the QoS advertising and routing scalable. Our extensive simulations confirm both contributions of the QoS extension to BGP very well. Moreover, besides BGP, these statistical metrics can be applied to other networks and protocols to represent QoS information in a more scalable and precise way.     

认知网络中的拥塞规避多径路由算法

链路拥塞导致的数据包传输延时或者数据包丢弃使得网络无法保证业务的Q0S,而目前普遍使用的链路状态路由算法不具有拥塞响应机制.本文针对以上问题,提出了一种能够快速规避拥塞的多径路由算法,该算法通过改进蚂蚁算法,在拥塞发生时采用双向蚂蚁寻路的方法,提高了新路径搜索的速度;使用新的寻路准则使其更满足认知网络的QoS需求.使用...     

无线Ad Hoc网络中的QoS路由协议

无线Ad Hoc网络的应用环境以及与Internet的互连都要求其必须提供一定的服务质量(QoS)保证,QoS路由技术是在无线Ad Hoc网络中实现QoS的重要方法。本文对近年来国内外在无线Ad Hoc网络中的QoS路由技术方面取得的研究成果进行了全面的概括总结和分类,对资源预留路由、多径路由和跨层优化路由3类QoS路由协议进行比较分析,并且提出了QoS路由技术亟待解决的问题和今后的发展方向。     

Integrated Social and QoS Trust-Based Routing in Delay Tolerant Networks

We propose and analyze a class of integrated social and quality of service (QoS) trust-based routing protocols in mobile ad-hoc delay tolerant networks. The underlying idea is to incorporate trust evaluation in the routing protocol, considering not only QoS trust properties but also social trust properties to evaluate other nodes encountered. We prove that our protocol is resilient against bad-mouthing, good-mouthing and whitewashing attacks performed by malicious nodes. By utilizing a stochastic Petri net model describing a delay tolerant network consisting of heterogeneous mobile nodes with vastly different social and networking behaviors, we analyze the performance characteristics of trust-based routing protocols in terms of message delivery ratio, message delay, and message overhead against connectivity-based, epidemic and PROPHET routing protocols. The results indicate that our trust-based routing protocols outperform PROPHET and can approach the ideal performance obtainable by epidemic routing in delivery ratio and message delay, without incurring high message overhead. Further, integrated social and QoS trust-based protocols can effectively trade off message delay for a significant gain in message delivery ratio and message overhead over traditional connectivity-based routing protocols.     

QoS routing based on mobile agent for LEO satellite IP networks

Current quality of service (QoS) routing schemes for low earth orbit (LEO) satellites IP networks either neglect the varying population density or fail to guarantee end-to-end delay. As a remedy, QoS routing protocol based on mobile agent (QoSRP-MA) is proposed. QoSRP-MA is a source-based routing protocol. Once connection requests arrive, QoS mobile agents are dispatched from ingress satellite to explore routes, which migrate using satellite routing tables. Upon arriving in egress satellite, QoS mobile agents migrate back towards ingress satellite to reserve bandwidth. To construct satellite routing tables, load balancing routing algorithm based on mobile agent (LBRA-MA) is presented. In LBRP-MA, at regular intervals mobile agents launched on all satellites migrate autonomously to evaluate path cost and update routing tables. Moreover, path cost between source and destination is evaluated considering satellite geographical position as well as inter-satellite link (ISL) cost. Furthermore, ISL congestion index is considered to update routing table. Through simulations on a Courier-like constellation, it shows that QoSRP-MA can achieve guaranteed end-to-end delay bound with higher throughput, lower connection failing ratio and signaling overhead compared to high performance satellite routing (HPSR) scheme.     

安全保障：无线Mesh网络中支持QoS的DSR路由协议的改进与实现

随着无线Mesh网络传输多媒体业务需求的增加,要求网络支持服务质量（QoS）,本文基于DSR协议设计了一个支持QoS的路由协议算法QDSR（QoS-DSR）。该算法保证了数据流的带宽、时延的QoS需求,根据路径跳数和节点拥塞情况定义路由代价函数,选择最优路径。仿真结果表明,与DSR相比,QDSR提高了网络吞吐量,降低了平均端到端延时,提高了网络利用率,更好地满足业务的QoS需求,并且具有更强的适用性和可扩展性。     

A Survey of Routing Protocols that Support QoS in Mobile Ad Hoc Networks

The explosive growth in the use of mobile devices coupled with users' desires for real-time applications has provided new challenges in the design of protocols for mobile ad hoc networks. Chief among these challenges to enabling real-time applications for mobile ad hoc networks is incorporating support for quality of service (QoS), such as meeting bandwidth or delay constraints. In particular, it is important that routing protocols incorporate QoS metrics in route finding and maintenance to support end-to-end QoS. This article extensively and exclusively studies the issues involved with QoS-aware routing and presents an overview and comparison of existing QoS-aware routing protocols. In addition, the open issues that must be addressed to fully support QoS-aware routing are discussed.