Voice and Internet Multimedia in UMTS Networks

Voice telephony is the predominant service on today's cellular mobile networks, in terms of number of customers, revenues and network usage. However, it is difficult to predict how long this will be the case given the rising demand for new Internet multimedia services. It is therefore essential that 3rd generation (3G) mobile networks support a voice telephony service, but also that these networks are also capable of providing Internet multimedia services using the same technology.This paper provides an overview of how voice telephony is provided in the initial phase of the universal mobile telecommunications system (UMTS). It then describes how this is expected to evolve in later phases — so that voice telephony becomes one of a large number of multimedia services provided from a common Internet protocol-based mobile network.     

Fast channel access and DCA scheme for connection andconnectionless-oriented services in UMTS

An efficient MAC protocol and flexible dynamic channel allocation (DCA) scheme for the UMTS-TDD mode is presented which exploits the characteristics of connectionless and connection-oriented services. The proposed protocol gives fast channel access and high bandwidth efficiency in any traffic scenario asymmetric between uplink and downlink channels, particularly in the presence of Internet traffic     

Traffic and Interference Adaptive Scheduling for Internet Traffic in UMTS

In this paper we propose a scheduling strategy for the radio resources management when transmitting Internet traffic over third-generation systems. More precisely, we consider the UMTS Terrestrial Radio Access Network (UTRAN) Time Division Duplex (TDD) mode standardized by ETSI. UTRAN TDD uses a hybrid solution of code and time division multiple access, called TD-CDMA. In UMTS systems a key issue in developing access methodologies for the available spectrum is an optimal management of the rare radio resources. In this paper we present a fair and efficient scheduling algorithm that adapts its behavior to traffic and interference conditions. Specifically, our scheduling algorithm is able to manage the radio resources taking into account both the traffic fluctuations in the uplink and downlink direction and the variations of the system interference. The goal of our scheduler is the data-throughput maximization for an efficient utilization of available radio resources. The effectiveness of our scheduling algorithm is shown by exploiting analytical tools.     

因特网IP QoS机制及其在UMTS网络中的应用

目前广泛使用的因特网协议(IP)已经成为所有数据业务的传输标准。传统的因特网业务策略(BE策略)不能满足新兴的实时业务的需求,因此有必要引入IPQoS机制来更有效的分配资源。由于第三代通信系统网UMTS需要同时支持非实时和实时业务,而且无线网的资源和设备比固定网昂贵得多,所以IPQoS机制对于无线网络尤为重要。文中首先研究因特网IPQoS机制,然后讨论如何将其应用到UMTS网络中。     

IDC的互联网接入方案研究

本文以互联网数据中心(IDC)的互联网接入方案制定为研究对象,采用层次化、模块化的设计方式对单节点IDC的互联网接入网络进行设计,由此引申提出了3种多节点IDC的互联网接入解决方案,并根据各互联网接入方案的特点,分析了多节点IDC互联网接入方案的各自适用场景。     

UMTS integrated with B-ISDN

Since, by the turn of the century, a mobile terminal will be involved in 50 percent of all calls, it is critical that the integration of the fixed and mobile telecommunication systems succeeds. This will require that B-ISDN support some features necessary to provide mobility services to the users. In the scenario discussed in the present article, the UMTS base stations are connected to a B-ISDN local exchange using the same user-network-interface (UNI) as B-ISDN fixed network terminals. Therefore, many of the aspects discussed in the article are related to the UNI     

Securing your Internet connection: a sequel

This author discusses the problem of Internet security. He draws some parallels between spammers trying to trick victims to opt out of their e-mail list in order to obtain information on valid e-mail addresses with so-called social engineering techniques used by security perpetrators. The term social engineering is typically used to describe a human-interactive (the emphasis is on the word human as opposed to computer-based) process that tricks people into violating security policies and procedures to get unauthorized access to protected information exposing security vulnerabilities. The best way to deal with social engineering threats is through creating and enforcing strict security procedures through education and training     

Wireless Internet access for mobile subscribers based on theGPRS/UMTS network

With the advent of IP technologies and the tremendous growth in data traffic, the wireless industry is evolving its core networks toward IP technology. Enabling wireless Internet access is one of the upcoming challenges for mobile radio network operators. The General Packet Radio Service is the packet-switched extension of GSM and was developed to facilitate access to IP-based services better than existing circuit-switched services provided by GSM. We illustrate how a visited mobile subscriber on a GPRS/UMTS network can access his/her home network via the gateway GPRS support node (GGSN). We also propose some implementation ideas on wireless Internet access for a remote mobile subscriber based on a GPRS/UMTS network     

UMTS security

The Universal Mobile Telecommunications System (UMTS) is one of the new 'third generation' mobile cellular communication systems. UMTS builds on the success of the 'second generation' GSM system. One of the factors in the success of GSM has been its security features. New services introduced in UMTS require new security features to protect them. In addition, certain real and perceived shortcomings of GSM security need to be addressed in UMTS. This paper surveys the major security features that are included in the first releases of the UMTS standards.     

UMTS overview

The Universal Mobile Telecommunications System (UMTS) as specified by the Third Generation Partnership Project (3GPP) was formally adopted by the ITU as a member of its family of IMT-2000 Third Generation Mobile Communication standards in November 1999. This paper provides some background to the UMTS standard and an overview of the system architecture. Some information about the current status of technology trials is provided as well as predictions for the services that future UMTS networks are likely to deliver to the end user     

UMTS鉴权原理及其与GSM鉴权兼容性

介绍了第三代移动通讯系统UMTS的安全体系,重点介绍UMTS的鉴权流程,鉴权原理和相关算法,并且对UMTS和GSM的鉴权兼容性进行了探讨。     

基于GPRS／UMTS网络的无线Internet接人及MIP技术在其中的应用

随着GPRS/UMTS网络的即将投入商用和Internet网络及其业务的飞速发展 ,如何将这两种通信网络进行合理的融合以利用两者的不同优势实现更加快捷方便的网络服务越来越受到包括网络运营商 ,设备供应商乃至理论研究界的广泛关注。本文就这一课题详细介绍了目前通信业界的最新相关研究成果 ,并讨论了MIP技术在这一融合过程中的积极应用。     

Die Vision UMTS

The Universal Mobile Telecommunications System UMTS is the European vision of a 3^rd generation mobile telecommunications system. UMTS will carry on the world-wide success of the European 2^nd generation system, GSM, which now (in February 1998) has 66 million subscribers and 239 operators. The evolution towards UMTS will show both: On the one hand a new air interface will allow multiple users to communicate with several media simultaneously, i.e. transmitting and receiving voice, data, text, images, audio and video at a maximum data rate of 2 Mbit/s. On the other hand enhanced, intelligent networks will support the mobility of users with UMTS-, GSM- and cordless phones. UMTS will be a major contribution to the convergence of telecommunications, broadcasts and computers, setting a milestone on our way towards a global information society.     

UMTS mobility management

The characteristics of first, second and third generation mobile communication systems are first described. The state of standardisation of the universal mobile telecommunication system (UMTS) is then outlined and the system concept is introduced. A mobility management platform which will provide uniform access to mobility functions for every user or network entity independent of the actual location of the requested function in the network is described. The mobility management platform is based on the intelligent network concept. Mobility management aims to share the processing load in the distributed UMTS environment     

采用IntServ-over-DiffServ的UMTS全IP接入方案

讨论UMTS系统全IP接入的QoS问题，提出一种采用IntServ-over-DiffServ的全IP接入方案，以解决UTRAN网络中的QoS问题。该方案在节点B和无线网络控制器之间建立区分服务域，并在其中使用聚合RSVP技术，既保证了网络的扩展性，又能够向业务流提供良好的QoS支持。     

UMTS与WCDMA

随着第三代移动通信技术(下面简称3G)商用化的临近 ,与3G技术有关的术语也日渐流行 ,诸如WCDMA、UMTS、TD_SCDMA等频繁出现在大众媒体上。一个较为普遍的现象是 ,人们往往将WCDMA和UMTS等同视之 ,UMTS和WCDMA到底是什么关系呢?他们有没有什么区别呢?早在20世纪90年代初期 ,欧洲电信标准协会 (ETSI)就开始为3G标准征求技术方案 ,并雄心勃勃地把3G技术统称之为UMTS(UniversalMobileTelecommunicationsSystem) ,意即通用移动通信系统 ,宽带CDMA(带宽5MHz)建议是其多种方案之一。其后 ,日本的积极参与极大地推动了3G标准…     

UMTS中的QoS

3G系统中,骨干和核心网全部采用IP或ATM标准,又有多业务种类的情况,再加上有庞大的前期开销和更高的传输速度,都要求必须提供强大的QoS管理,使业务QoS管理和系统资源QoS的管理都达到较高要求。UMTS与Internet QoS映射目前研究的一个热点是3G中的UMTS（Universal Mobile Telecom-munication System）与Internet QoS的映射,但还没有完全的结论。因为3G系统预计将来的传输都是基于IP/ATM的,这样充分利用了有线系统的优势,并能实现顺利地平滑过渡,同时提供一定的QoS。Internet只提供尽力而为的业务标准,没有时间限制…     

UMTS的移动性管理

移动性管理是移动通信中是最为重要的特征之一，而移动性管理最重要的特征是解决UE移动时通信不间断的问题。UMTS是从原先的GSM系统演进的3G标准之一。它的移动性管理也是从GSM的移动性管理演进的，具有很多原先GSM基于电路交换的移动性管理的特征。而在UMTS中，分组业务占有很大的比例。而且在新的全IP结构中，分组域会取代电路域。原先的移动性管理在分组域的一些应用场合有很多局限性，这就要求引入新的移动性管理技术。在3G的几个标准的标准化过程中，都引入了一种新的移动性技术——移动IP技术。3GPP在制定UMTS的移动性管…