基于IP的3G服务质量控制及实现

第三代移动通信系统 (3G)的第二阶段是采用IP传送网 ,服务质量 (QoS)是极其重要的问题。在讨论基于IP的 3G中QoS体系结构、业务QoS要求基础上 ,重点研究QoS控制原理和区分服务的实现 ,并得出一些有参考价值的结论。     

基于IP的WCDMA R4业务承载网络建设的探讨

WCDMA R4版本核心网电路域和分组域实现了承载方式的统一,文章在对3G 业务对IP承载网QoS需求分析的基础上,重点讨论了基于IP技术的WCDMA R4业务 承载网的建设思路以及在3G IP承载网上的QoS策略问题。     

基于IP的WCDMA R4业务承载网技术研究

在分析3G业务IP承载网QoS需求的基础上,重点讨论了基于IP技术的WCDMA R4版本业务承载网的建设思路及IP业务承载网的QoS策略问题.     

3G中的QoS结构及无线资源分配策略

在3G（第3代移动通信系统）中，为了给不同类型的业务提供不同级别的端到端QoS，网络资源必须进行合理分配。QoS和资源分配是密不可分的，而无线资源分配显得尤为重要。文中提出了UMTS的QoS结构，分3部分对空中接口部分的QoS（即无线资源分配策略问题）进行了讨论：首先提出了一种RRA算法，接着讨论了W－CDMA和TD－CDMA系统的无线资源分配问题，最后讨论了下行链路及上行链路的呼叫允许控制（CAC）。     

3G接入传输网络建设分析

由3G WCDMA标准规定的3G网络模型,提出了3G传输网的分层结构,重点分析了3G UTRAN层网络业务特点、QoS要求和传输接口,提出了适合3G应用的接入传输组网方案,并从3G业务应用开展和R5版本演进趋势分析,提出了后续3G演进应在UTRAN层优选提供IP接口,并根据业务容量和技术实现优势,综合考虑业务的QoS保障和建网成本优化,提出了适合3G演进发展的接入层传输组网方案.     

B3G系统中一种新的无线资源分配策略

如何合理地利用有限的无线资源,保证链路里传输的各种业务的QoS,同时提供较低的操作和管理开销,从而保证实现B3G系统中的新业务的发展,是无线资源分配策略设计的重点。提供了B3G系统中一种新的无线资源分配策略,并利用OPNET Modeler建立了一个仿真平台对协议算法进行了验证。仿真结果显示,该策略具有很高的资源分配效率,并能针对不同业务的不同需求提供不同的时延保障,对B3G系统QoS框架中的3种业务都能提供良好的支持,并已应用于B3G原型系统。     

CDMA2000分组数据预付费业务的解决方案

3GPP2针对CDMA2000制定了一个分组数据结构,可以为3G用户提供基于简单IP和移动IP的IP接入服务。3GPP2无线IP服务(P.S0001)中目前公布的规范规定支持基于用户IP地址的脱机计费,并提供了选项,为用户预先定义的远程IP地址提供计费支持。2002年,3GPP2分组数据委员会一直努力在C版的无线IP服务规范中定义新的计费机制(参见X.P0011.6),以支持联机计费服务,更具体地说是基于3GPP2分组数据结构的预付费联机计费业务,其结构示意如图1所示。预付费客户端(PPC)和预付费服务器(PPS)之间的通信通过Radius+基础设施实现。归属AAA(HAAA…     

Qos漫谈

简单介绍了QoS(Quality ofService）的实现要求以及在无线局域网中的作用，并较为全面地列举了QoS的一些常用术语，如竞争服务、服务水平协议、加权公平序列（WFQ）等。然后介绍了IETF在广域网上定义的两种IP QoS结构（Intr-Serv与Diff-Serv）和IEEE有关在无线局域网（WLAN）中加入QoS相关内容的3个待选机制，最后强调了IP QoS在3G应用中的重要作用。     

移动IP网络的QoS技术研究

目前各大通信运营商已经建立了IP化核心网，并向全网IP化阶段演进，QoS技术是IP网络发展的重要基础技术之一，既要加强研究又要注重实用性。本文从QoS技术在3G业务IP网络上的应用出发，分析了3G的IP承载网QoS保证机制及其可靠性。     

IP承载网及其3G/NGN业务的QoS方案

文章介绍了IP承载网的产生、发展及网络架构,分析了IP承载网承载3G/NGN电信级业务时的QoS核心需求,进一步给出了IP承载网QoS需求的具体解决方案。     

CDMA EVDO网络中的QoS保障机制研究

随着3G无线分组网络的飞速发展,基于移动终端的实时多媒体业务需求也日趋广泛.如何保障诸如流媒体直播和可视通话等QoS要求较高的业务,必将成为一个重要的课题.对CDMA EVDO网络中的QoS保障机制进行了初步探讨,阐述了CDMA EVDO网络的QoS实现架构,并以终端MS源发呼叫的QoS协商过程为例,描述了其信令流程.     

QoS Provisioning with New Effective Bandwidth/Buffer Calculation Scheme in Wireless IP Networks

The huge commercial success of mobile telephony, the phenomenal growth of Internet users, the popularity of IP-based multimedia applications are the major driving forces behind third-generation (3G), ongoing Byond 3G (B3G), and forth-genertion (4G) evolution. 3G brought wired applications, both data and multimedia, into wireless environments. It operates on IP-based infrastructures to provide wider service access capability. To support and satisfy QoS (Quality of Service) of diverse IP-based multimedia applications, traffic management, such as Connection Admission Control (CAC) and resource allocation, becomes essential. CAC and resource allocation are computationally complex when combined with QoS guarantee for traffic with different characteristics. However, CAC and resource allocation are real-time traffic control procedures. Hence, processing load should be minimized to reduce delay. At the same time, network resources should be utilized efficiently to accommodate more users. However, reducing processing load and obtaining high resource utilization efficiency has been considered to be contradictory matter. In addition, CAC and resource allocation schemes which consider multiple QoS criteria – loss and delay – simultaneously have not been adequately studied. Simultaneous QoS consideration is important to satisfy stringent and diverse QoS requirements of multimedia traffic. In this paper, we propose a nobel effective bandwidth/buffer calculation method based on a virtual channel/buffer analysis scheme. We show that our method can achieve high resource utilization efficiency with reduced processing load. Moreover, we show that our scheme allows for simultaneous consideration of multiple QoS criteria, loss and delay.     

QoS Provisioning in Wireless IP Networks

This paper deals with quality of service (QoS) provision in wireless IP networks. QoS provision is particularly challenging in wireless networks, where network resources are generally limited, variable over time and shared. In the design of possible measures to assure QoS one should consider that standardization is well established for the network layer Internet Protocol and for many underlying technologies of frequent use (e.g. IEEE 802.11, BLUETOOTH or HIPERLAN II). Therefore, as far as research on QoS is concerned, there is little room in both the IP and the link-layers for improved IP over wireless interfaces. In this paper we illustrate a solution in which an intermediate Wireless Adaptation Layer (WAL) is transparently interposed between the IP layer and specific link-layer technologies as a solution to provide QoS. The WAL addresses two main issues: (i) compensation for channel impairments in different platforms in order to enhance wireless channel reliability and (ii) implementation of traffic control and packet scheduling mechanisms to satisfy bandwidth and delay requirements, as well as to enforce a general principle of fairness among the IP associations contending for network resources and achieve optimal exploitation of transmission capacity. The WAL consists of a set of modules, each one in charge of a specific task, which can be enabled or disabled depending on the specific network environment. The novelty of the WAL approach is its capability of adapting itself to different wireless interfaces selecting performance enhancing modules for specific networks. This requires to modify the standard TCP/IP protocol stack by introducing an intermediate layer between the IP layer and the Data Link layer, with performance enhancement purposes. This paper focuses on two modules in particular, namely a traffic control module, which is in charge of performing congestion control and channel state dependent scheduling (CSD) packet scheduling, and a forward error correction (FEC) module, which compensates for channel impairments. This paper presents the proposed architecture provided with these modules and reports some measurements and simulations highlighting benefits resulting from the use of such modules.     

Traffic Aided Uplink Opportunistic Scheduling with QoS Support in Multiservice CDMA Networks

In this letter, we address the problem of resource allocation with efficiency and quality of service (QoS) support in uplink for a wireless CDMA network supporting real‐time (RT) and non‐realtime (NRT) communication services. For RT and NRT users, there are different QoS requirements. We introduce and describe a new scheme, namely, traffic aided uplink opportunistic scheduling (TAUOS). While guaranteeing the different QoS requirements, TAUOS exploits the channel condition to improve system throughput. In TAUOS, the cross‐layer information, file size information, is used to improve fairness for NRT users. Extensive simulation results show that our scheme can achieve high system throughput in uplink wireless CDMA systems, while guaranteeing QoS requirements.     

QoS Recovery Schemes Based on Differentiated MPLS Services in All-Optical Transport Next Generation Internet

The Internet is evolving from best-effort service toward an integrated or differentiated service framework with quality-of-service (QoS) assurances that are required for new multimedia service applications. Given this increasing demand for high bandwidth Internet with QoS assurances in the coming years, an IP/MPLS-based control plane combined with a wavelength-routed dense wavelength division multiplexing (DWDM) optical network is seen as a very promising approach for the realization of future re-configurable transport networks. Fault and attack survivability issues concerning physical security in a DWDM all-optical transport network (AOTN) require a new approach taking into consideration AOTN physical characteristics. Furthermore, unlike in electronic networks that regenerate signals at every node, attack detection and isolation schemes may not have access to the overhead bits used to transport supervisory information between regenerators or switching sites to perform their functions. This paper presents an analysis of attack and protection problems in an AOTN. Considering this, we propose a framework for QoS guarantees based on the differentiated MPLS service (DMS) model and QoS recovery schemes against QoS degradation caused by devices failures or attack-induced faults in an AOTN. We also suggest how to integrate our attack management model into the NISTs simulator—modeling, evaluation and research of lightwave networks (MERLiN).     

Power Control Based QoS Provisioning for Multimedia in W-CDMA

Third generation wireless communication systems will support multimedia, and W-CDMA will be the common air interface technology. Due to the interference limited nature of CDMA, power is the main resource of the network, and power control is a means of resource management. In this article, we introduce Dynamic Resource Scheduling (DRS) as a framework which employs power control for QoS provisioning of multimedia traffic in W-CDMA. In DRS, we propose the application of optimal power assignment to the W-CDMA architecture, and we also suggest several implementation strategies. A simulation model of the Japanese W-CDMA standard (ARIB) has been developed for performance evaluation. The DRS framework is shown to accommodate different service classes efficiently by optimal resource management. Quantitative advantages are proven in terms of gains in capacity, throughput, power saving and QoS stability.     

一种基于区分服务和AMR编码技术的VoIP QoS解决方案

文章提出了一个将网络和终端相结合的VoIPQoS方案.该方案在网络提供区分服务的基础上,终端采用AMR(Adaptive Multi-Rate)语音编码技术,编码率根据网络状况自适应地调整.模拟实验表明,此方案能够较好地使网络和终端协调工作来保证QoS.     

QoS-Based Admission and Load Control Algorithm for Integrated Voice/Data Services over Wideband CDMA

In order to maximize the system capacity in third generation wireless system, efficient call admission and load control algorithms are required to handle the different services having diverse traffic patterns and Quality of Service (QoS) requirements. We propose an admission and load control algorithm that considers the network loading information, propagation conditions, and the interference level. The algorithm takes advantage of the new features of third-generation (3G) wireless system such as the reported pilot measurements, auxiliary pilot for smart antennas, and variable spreading gain. Dynamic resource allocation is employed to scale the amount of the assigned radio resources taking the network loading conditions and channel characteristics into consideration. The results show that integrating the voice service and the data service with high transmission rate (>144 Kbps) can be realized using efficient resource management.     

CDMA 2000 1xEVDO Rev.A系统的QoS应用

随着数据用户和数据业务的迅猛发展,运营商网络的承载压力不断加大,如何综合考虑网络资源利用最大化和用户间公平性,是目前网络运行商面临的主要问题。文章对QoS概念、QoS模型、3G业务的QoS分类以及CDMA 2000 1xEVDORev.A端到端QoS的体系结构进行了说明,并对EVDORev.A系统中端到端QoS保证的系统实现进行了介绍。文章认为第三代无线通信技术CDMA 2000 1xEVDORev.A能提供端到端的QoS解决方案,它不仅增强了对实时业务的支持,还可以大大提升网络服务性能。     

宽带无线IP系统中基于区分服务的QoS实现策略

讨论了在宽带无线IP系统中实现QoS的问题。提出了一个基于区分服务(DiffServ)的QoS框架,并针对无线链路上的高误码率、窄带宽、性能变化剧烈、用户移动性等特点,对DiffServ进行了加强,并提供了一种针对业务类型的用户接入控制机制。仿真结果显示了该QoS框架的性能。