一个可切实服务于运营商的移动无线因特网

本文在简单介绍了移动IP及其路由优化，无线局域网（WLAN）和GPRS的基础上，提出了一个新的利用移动IP来融合WLAN和GPRS的移动无线因特网的网络结构，详细论述了其多连接的路由过程，平滑垂直切换，AAA，并做了简要的性能分析。     

移动IP在异构网络互联中的应用

本文介绍了移动IP及无线局域网(WLAN)和GPRS及采用移动IP来融合WLAN和GPRS的方法，对移动IP在混合网间的切换问题做了详细的论述。     

移动IP无线局域网的网络性能研究

文章阐述了移动IP无线局域网运行的网络机制，并利用OPNET Modeler网络仿真软件建立该机制下的移动IP无线局域网模型．分析评估网络性能。仿真结果表明．这种移动IP无线局域网性能优良，具有很好的发展前景。     

GPRS承载的WAP无线应用与移动数据处理

移动通信与IP技术的融合产生了基于移动通信的IP数据业务技术。以GPRS组用分组无线业务为承载系统，利用WAP技术进行移动数据信息的查询和处理，可以充分利用GPRS的IP分组、高效、永远在线等特性，为企业提供无线数据服务。     

OWLAN网络和移动性管理

简要介绍运营商无线局域网(OWLAN)的产生背景及技术概况,重点研究在本地和漫游情况下,OWLAN的终端之间以及终端与固定主机(FES)之间进行数据通信的各种情况。文章参照GPRS、TCP/IP和移动IP中的多种地址解析和路由协议,提出一种OWLAN的地址解析机制。     

WLAN与2.5/3代移动通信网的结合

文章探讨了无线局域网与蜂窝移动数据网互连与结合的机制,介绍了无线局域网与GPRS、cdma2000 1x、WCDMA等几种网络实现互连与结合的解决方案。     

移动运营商WLAN建设方案

无线局域网(WLAN)正在从有线局域网的延伸逐渐转变为一种宽带无线接入手段,并将对最终用户的发展产生深远的影响。无线局域网与GPRS、3G实际上可以成为一种相互促进、相互拓展、相互完善的关系,通过弥合技术之间的差异,形成双赢局面。移动运营商如能将无线局域网与GSM/GPRS相结合,将会形成比其他运营商更具竞争力的具有移动特色的无线局域网     

移动通信系统从1G到4G的演进

第2代(2G)的数字移动通信由单纯的语音通信转移到提供语音、图像、文字等综合信息的传输,并能无线接入因特网.2G系统的传输速率难以满足人们对移动多媒体信息以及移动数据传输的需求.3G的核心网是从2G演进而来,但并不是传输TCP/IP数据包的最优结构.4G系统将是基于TCP/IP的核心网,混合OFDM和CDMA的无线接入方式,分离的接收、发射基站,基于无线ad hoc网络的结构而非蜂窝结构.     

集成移动IP的无线局域网

文章分析无线局域网的不足和应采取的相应对策,介绍集成移动IP无线局域网的基本体系结构,研究集成移动IP无线局域网的协议栈,提出新的子层———IP关口层,详细分析无线局域网在IP关口层和数据链路层对移动IP的支持。     

移动IP在移动通信核心网中的发展

本阐述了移动IP、GPRS、UMTS的概念及移动通信网络中具有移动IP功能的核心网的发展阶段。     

IEEE 802.11 roaming and authentication in wireless LAN/cellular mobile networks

A wireless LAN service integration architecture based on current wireless LAN hot spots is proposed so that migration to a new service becomes easier and cost effective. The proposed architecture offers wireless LAN seamless roaming in wireless LAN/cellular mobile networks. In addition, a link-layer-assisted mobile IP handoff mechanism is introduced to improve the network/domain switching quality in terms of handoff delay and packet loss. An application layer end-to-end authentication and key negotiation scheme is proposed to overcome the open-air connection problem existing in wireless LAN deployment. The scheme provides a general solution for Internet applications running on a mobile station under various authentication scenarios and keeps the communications private to other wireless LAN users and foreign network. A functional demonstration of the scheme is given. The research results can contribute to rapid deployment of wireless LANs.     

Wireless LAN access network architecture for mobile operators

The evolution of IP-based office applications has created a strong demand for public wireless broadband access technology offering capacity far beyond current cellular systems. Wireless LAN access technology provides a perfect broadband complement for the operators' existing GSM and GPRS services in an indoor environment. Most commercial public wireless LAN solutions have only modest authentication and roaming capability compared to traditional cellular networks. This article describes a new wireless LAN system architecture that combines the WLAN radio access technology with mobile operators' SIM-based subscriber management functions and roaming infrastructure. In the defined system the WLAN access is authenticated and charged using GSM SIM. This solution supports roaming between cellular and WLAN access networks and is the first step toward an all-IP network architecture. The proto-type has been implemented and publicly verified in a real mobile operator network     

Cellular access control and charging for mobile operator wireless local area networks

This article presents a system architecture, design considerations, and rationale for a mobile operator wireless LAN. The article also discusses the system implementation and performance issues. The system presented reuses GSM and GPRS mechanisms for user authentication, access control, subscriber management, operator roaming, and billing, while still being compatible with wireless Internet service provider networks and IETF and IEEE protocols such as RADIUS, EAP, and IEEE 802.1x. The architecture is a result of research carried out by Nokia between 1999 and 2002. The designed architecture has also been verified in a complete system implementation.     

Intelligent Handoff for Mobile Wireless Internet

This paper presents an intelligent mobility management scheme for Mobile Wireless InterNet – MWIN. MWIN is a wireless service networks wherein its core network consisting of Internet routers and its access network can be built from any Internet-capable radio network. Two major standards are currently available for MWIN, i.e., the mobile IP and wireless LAN. Mobile IP solves address mobility problem with the Internet protocol while wireless LAN provides a wireless Internet access in the local area. However, both schemes solve problems independently at different layers, thereby some additional problems occur, e.g., delayed handoff, packet loss, and inefficient routing. This paper identifies these new problems and performs analyses and some real measurements on the handoff within MWIN. Then, a new handoff architecture that extends the features of both mobile IP and wireless LAN handoff mechanism was proposed. This new architecture consists of mobile IP extensions and a modified wireless LAN handoff algorithm. The effect of this enhancement provides a linkage between different layers for preventing packet loss and reducing handoff latency. Finally, some optimization issues regarding network planning and routing are addressed.     

Supporting IP QoS in the General Packet Radio Service

The General Packet Radio Service is the current enhancement in the GSM infrastructure, capable of handling Internet protocol traffic for mobile computing and communications. A major deficiency of the current GPRS specification is the lack of adequate IP quality of service support. Two schemes for enhancing the GPRS architecture with the existing IP QoS support architectures, IntServ and DiffServ, are proposed. Solutions are proposed to the problem of establishing QoS reservations across the GPRS core network, and the required signaling enhancements and modifications in the components of the GPRS architecture are identified. Of the two proposed schemes the IntServ one requires frequent refreshing of state information and extra signaling. To quantify the effect that signaling overhead has on GPRS operation and performance, a simulation model of the proposed IntServ architecture was developed, which includes models of the GPRS cellular infrastructure, network traffic, and user movement. The obtained simulation results show that the proposed IntServ architecture demonstrated good scalability, even for large user populations     

End-to-End Adaptive QoS Provisioning over GPRS Wireless Mobile Network

The General Packet Radio Service (GPRS) offers performance guaranteed packet data services to mobile users over wireless frequency-division duplex links with time division multiple access, and core packet data networks. This paper presents a dynamic adaptive guaranteed Quality-of-Service (QoS) provisioning scheme over GPRS wireless mobile links by proposing a guaranteed QoS media access control (GQ-MAC) protocol and an accompanying adaptive prioritized-handoff call admission control (AP-CAC) protocol to maintain GPRS QoS guarantees under the effect of mobile handoffs. The GQ-MAC protocol supports bounded channel access delay for delay-sensitive traffic, bounded packet loss probability for loss-sensitive traffic, and dynamic adaptive resource allocation for bursty traffic with peak bandwidth allocation adapted to the current queue length. The AP-CAC protocol provides dynamic adaptive prioritized admission by differentiating handoff requests with higher admission priorities over new calls via a dynamic multiple guard channels scheme, which dynamically adapts the capacity reserved for dealing with handoff requests based on the current traffic conditions in the neighboring radio cells. Integrated services (IntServ) QoS provisioning over the IP/ATM-based GPRS core network is realized over a multi-protocol label switching (MPLS) architecture, and mobility is supported over the core network via a novel mobile label-switching tree (MLST) architecture. End-to-end QoS provisioning over the GPRS wireless mobile network is realized by mapping between the IntServ and GPRS QoS requirements, and by extending the AP-CAC protocol from the wireless medium to the core network to provide a unified end-to-end admission control with dynamic adaptive admission priorities.     

无线局域网帧数据流量研究

无线局域网中的信道要比有线局域网信道复杂的多,运载其上的流量研究成为评估和了解无线局域网行为模式的关键。比较了有线和无线局域网在体系结构和协议机制上的差异,进而分析了由于这种差异所导致的IP层数据包流量和MAC层帧数据流量不同之处,提出了无线局域网流量研究中存在的问题,探讨了无线局域网帧数据流量的研究内容和方向。     

Running cellular/PWLAN services: practical considerations for cellular/PWLAN architecture supporting interoperator roaming

To offer wireless data access services that are more efficient than GPRS or UMTS networks, public WLANs are in a predominant position to embrace the wireless broadband era. Reusing the existing mechanisms for user authentication, access control, billing, and roaming handling procedures in mobile territory to construct a complementary network, public WLAN (PWLAN) has drawn the attention of cellular operators such as Vodafone and T-Mobile. In this article we aim to investigate a practical end-to-end PWLAN architecture capable of using GPRS/UMTS SIM-based authentication for current mobile users and carrying out Web-based authentication for occasional users without SIM modules simultaneously. Additionally, we consider a confederation of various PWLAN service providers by a RADIUS-based roaming mechanism to leverage the existing resources of cellular operators. The proposed considerations and guidelines provide a baseline skeleton to build an extendable environment and successfully construct a flexible cellular/PWLAN hotspot in mobeeLAN service.     

One-pass GPRS and IMS authentication procedure for UMTS

Universal Mobile Telecommunications System (UMTS) supports Internet protocol (IP) multimedia services through IP multimedia core network subsystem (IMS). Since the IMS information is delivered through the general packet radio service (GPRS) transport network, a UMTS mobile station (MS) must activate GPRS packet data protocol (PDP) context before it can register to the IMS network. In the Third-Generation Partnership Project (3GPP) specifications, authentication is performed at both the GPRS and the IMS networks before an MS can access the IMS services. We observe that many steps in this 3GPP "two-pass" authentication procedure are identical. Based on our observation, this paper proposes an one-pass authentication procedure that only needs to perform GPRS authentication. At the IMS level, authentication is implicitly performed in IMS registration. Our approach may save up to 50% of the IMS registration/authentication traffic, as compared with the 3GPP two-pass procedure. We formally prove that the one-pass procedure correctly authenticate the IMS users.     

应用于移动环境中的WLAN接入网结构

文章介绍了把无线局域网接入与GSM,GPRS漫游融合在一起的运营无线局域网(OWLAN),分析了OWLAN的主要系统单元及功能,讨论了基于用户识别模块(SIM)的鉴权、漫游和计费机理。