3GPP系统架构演进(SAE)中的QoS探讨

针对不同的接入网技术和越来越高的用户需求,在SAE中实现端到端QoS显得尤为重要.本文详细介绍了SAE中引入的增强型QoS、QoS参数设置、用户数据承载级的区分控制和SAE中QoS协商过程,并分析了SAE中实现QoS有待解决的问题.     

浅谈下一代网络中的IPQoS关键技术

介绍了NGN中实现IP QoS的几种关键技术,IP QoS的体系架构,以及IP QoS对NGN中多媒体业务的支持。     

EVDO RevA网络QoS实现机制的研究分析

本文首先介绍了EVDO Rev A网络中实施QoS的重要意义、评价指标以及关键参数,分析了QoS的业务模型,从QoS架构、无线RAN和核心网深入研究了EVDO Rev A网络中QoS的实现机制,最后总结了QoS调度机制在EVDO Rev A网络运行中的应用。     

cdma2000无线接入系统中的QoS技术

本文首先介绍了cdma2000系统中QoS(Quality of Service)的基本概念、要求和QoS模型,然后对cdma2000无线接入系统中现有的QoS机制进行了分析和研究,同时论述了系统中与QoS实现有关的几个问题.     

UMTS及LTE／SAE网络端到端的QoS研究

通过对LTE／SAE系统的QoS与3GPPUMTS的QoS实现机制的分析与比较,介绍了移动通信网络中QoS的发展历程,最后概括介绍了基于策略和计费控制（PCC）架构的QoS研究。     

3G手机VoIP话音的QoS实现技术研究

在对3G手机VoIP话音QoS的主要实现技术进行分析的基础上,提出了3G手机VoIP话音QoS新的实现技术。文中通过对实时传输控制协议（RTCP协议）的详细研究,同时根据3G系统无线信道的具体特点,说明了实时传输控制协议运用于3G手机VoIP话音的QoS控制中的缺陷,并阐述了相应的控制解决方法。在基于Android的3G智能手机的VoIP客户端软件中,综合运用VoIP话音QoS的主要成熟实现技术,同时结合文中提出的VoIP话音QoS的解决思路,实现了对VoIP话音的QoS的控制。基于Android的3G智能手机的VolP客户端软件通过在不同的网络环境条件下的测试,VoIP话音质量良好,说明文中提出的3G手机VoIP话音QoS新的实现技术具有一定的实用价值。     

一种面向Web服务的QoS提供器模型

随着Web服务的广泛应用和发展，提供QoS保障能力是Web服务在商业应用中获得成功的关键因素．然而目前许多企业应用并没有提供面向QoS的Web服务，而修改已有的实现来满足客户对QoS需求的代价是非常高的．针对这一问题，本文提出了一个面向Web服务的QoS提供器模型，通过提供灵活的QoS处理器（QoS Handler）管理和部署机制，可以使原系统在不改变内部实现的情况下，向客户提供满足其QoS需求的Web服务．QoS提供器存应用服务器平台上进行了原型实现，结果表明它可以有效地为企业系统添加QoS保障．     

移动自组织网络QoS研究

由于自组网独特的特性,在该网络中支持QoS非常困难,需要进行系统研究。本文首先分析了自组网中QoS支持面临的挑战,接着从系统角度出发,结合自组网的特点,在QoS模型和QoS支持体系以及体系中具体的QoS技术等方面对自组网QoS支持做了详尽的分析与探讨,同时指出：定义自组网QoS模型需要综合考虑应用需求和网络特性;实现QoS模型可以采用分层QoS支持体系或跨层QoS支持体系,而后者将是今后研究的重点;结合路由层、MAC层和物理层的跨层QoS支持体系具有研究价值。     

宽带接入网络中的QoS保证

针对宽带接入网络中的高速率、高质量、安全性要求,引入了服务质量(QoS)保证技术。介绍了QoS的基本概念及相应规范,阐述了QoS在异步传输模式(ATM)中的实现机制、服务级别、技术参数的定义和表示计算方法,以及QoS在IP应用中的基本模型特征、实现机制和参数设置要求等,结合实例说明了宽带接入网络中QoS保证的应用。最后进行分析和阐述。     

基于MPLS的混合QoS机制研究

在分析和比较了各种QoS模型优缺点后,论文探讨了一种将DiffServ与MPLS相结合应用于一种特定通信网的混合QoS模型,描述了该模型中QoS机制实现原理。     

在基于GMPLS的无源光网络中支持端到端QoS

文章首先对下一代网络技术的发展趋势以及IETF服务质量（QoS）机制进行了简单介绍,然后对现有无源光网络技术对端到端QoS支持的不足进行了总结,提出了基于通用多协议标签交换（GMPLS）的无源光接入网QoS服务模型。通过在接入网中引入GMPLS通用控制和管理平台,建立了统一的QoS服务模型,实现了对端到端QoS的有效支持。     

Provisioning for interdomain quality of service: the MESCAL approach

This article presents an architecture for supporting interdomain QoS across the multi-provider global Internet. While most research to date has focused on supporting QoS within a single administrative domain, mature solutions are not yet available for the provision of QoS across multiple domains administered by different organizations. The architecture described in this article encompasses the full set of functions required in the management (service and resource), control and data planes for the provision of end-to-end QoS-based IP connectivity services. We use the concept of QoS classes and show how these can be cascaded using service level specifications (SLSs) agreed between BGP peer domains to construct a defined end-to-end QoS. We illustrate the architecture by describing a typical operational scenario.     

cdma2000 1xEV-DO系统中的QoS

本文首先介绍了cdma2000 1xEV-DO空中接口相关协议对QoS的支持,接着分别从无线接入网、核心网、骨干同三个方面讨论了1xEV-DO系统实现QoS的机制,最后指出了当前系统实现QoS面临的问题。     

QoS performance of optical burst switching in IP-over-WDM networks

We address the issue of how to provide basic quality of service (QoS) in optical burst-switched WDM networks with limited fiber delay lines (FDLs). Unlike existing buffer-based QoS schemes, the novel offset-time-based QoS scheme we study in this paper does not mandate any buffer for traffic isolation, but nevertheless can take advantage of FDLs to improve the QoS. This makes the proposed QoS scheme suitable for the next generation optical Internet. The offset times required for class isolation when making wavelength and FDL reservations are quantified, and the upper and lower bounds on the burst loss probability are analyzed. Simulations are also conducted to evaluate the QoS performance in terms of burst loss probability and queuing delay. We show that with limited FDLs, the offset-time-based QoS scheme can be very efficient in supporting basic QoS.     

一种新型的Ad hoc QoS多播路由协议

无线自组织（Ad hoc）网络的应用环境要求其必须提供一定的服务质量（QoS）保证，然而，无线信道固有的特点及节点移动造成网络拓扑的频繁变化，使得在无线Ad hoc网络中支持QoS较困难。可以采用Ad hoc QoS多播（AQM）协议通过事先预约邻居节点以跟踪资源的有效性等措施来解决这一问题。通过考虑传输时延、丢失率、带宽要求、时延抖动、吞吐量等QoS指标，寻找满足特定QoS要求的路由，AQM协议可以明显地改善多播通信的性能。网络仿真结果表明AQM协议基本适合Adhoc网络。     

一种在MPLS网络中支持QoS的流量工程算法

该文提出了一种改善QoS的队列调谐算法(QueueTuningAlgorithm:QTA),该算法应用于多协议标签交换(MPLS)流量工程。该算法通过把不同类别的业务,如传统的尽力而为(Best-Effort)业务和具有QoS需求的业务,映射到不同队列,然后根据链路的状况以及业务的QoS需求来进行队列调谐。QTA在实现负载均衡的同时又支持业务流的QoS,优化网络资源的利用。仿真表明该算法在MPLS网络中运行良好。     

Packet-switch mechanism based on QoS class mapping using flow label for overlay network

In the past few years, overlay networks have emerged as an alternative option for supporting value-added services such as fault tolerance, multicasting, and security. In this paper, we describe a quality of service (QoS) overlay network architecture for scalable, efficient and practical QoS support. In this architecture, we propose a flow label (FL)-based QoS class mapping method for QoS implementation, which can offer better scalability for applications and provide users with more refined QoS. Based on this method, a packet-switch mechanism using flow label is presented, depending on which, packets can be transmitted fast according to label, and more optimal paths can be chosen to guarantee the QoS requirement.     

移动自组网模糊逻辑QoS动态源路由算法

该文提出了一种新的移动Ad hoc网络QoS路由算法:模糊逻辑QoS动态源路由算法。算法从模糊理论的思想出发,将业务的多个QoS参数进行综合评判产生一类以语言变量描述的请求,在修改动态源路由协议为多径路由算法的基础之上,对比各条路径综合模糊路由状态,选择出最适合业务请求的路径。仿真显示算法在支持QoS的同时对移动Ad hoc网络因拓扑动态变化而引起的信息不精确性有很好的适应度。     

QoS‐Guaranteed Multiuser Scheduling in MIMO Broadcast Channels

This paper proposes a new multiuser scheduling algorithm that can simultaneously support a variety of different quality‐of‐service (QoS) user groups while satisfying fairness among users in the same QoS group in MIMO broadcast channels. Toward this goal, the proposed algorithm consists of two parts: a QoS‐aware fair (QF) scheduling within a QoS group and an antenna trade‐off scheme between different QoS groups. The proposed QF scheduling algorithm finds a user set from a certain QoS group which can satisfy the fairness among users in terms of throughput or delay. The antenna trade‐off scheme can minimize the QoS violations of a higher priority user group by trading off the number of transmit antennas allocated to different QoS groups. Numerical results demonstrate that the proposed QF scheduling method satisfies different types of fairness among users and can adjust the degree of fairness among them. The antenna trade‐off scheme combined with QF scheduling can improve the probability of QoS‐guaranteed transmission when supporting different QoS groups.     

Supporting packet-data QoS in next generation cellular networks

In the past few years, the Internet has grown beyond anyone's reasonable imagination into a universal communication platform. At the same time the cellular networks, with their ability to reach a person “anywhere, anytime,” have grown impressively as well. Thus the combination of mobile networks and the Internet into the so called “mobile Internet” promises to be an important technology area. The indications are clear: the cellular networks are rapidly adopting suitable network models for supporting packet data services. A key component of this packet data service model is quality of service (QoS), which is crucial for supporting disparate services envisioned in the future cellular networks. We describe the packet data QoS architecture and specific mechanisms that are being defined for multi-service QoS provisioning in the Universal Mobile Telecommunication Systems