GRA Based Network Selection in Heterogeneous Wireless Networks

4G wireless networks will integrate heterogeneous technologies such as Wireless LAN and third generation (3G) cellular networks and have the capability to offer various services at any time as per user requirements, anywhere with seamless interoperability at affordable cost. One important challenge in such a heterogeneous wireless environment is to enable network selection mechanisms in order to keep the mobile users always best connected anywhere and at any time. In this paper, a multi-criteria access network selection algorithm is proposed in Worldwide Interoperability for Microwave Access–Wireless Fidelity environment, in order to facilitate the provision of high quality services and at the same time to satisfy different types of user service level agreements. Analytical hierarchy process (AHP) and grey relational analysis (GRA) methods are applying for optimal access network selection. The proposed methodology combines the AHP to decide the relative weights of criteria set according to network’s performance, as well as the GRA to rank the network alternatives. The advantages of the GRA method are that the results are based on the original data, the calculations are simple and straightforward, and finally it is one of the best methods to make decision under heterogeneous wireless network environment.     

Mobile application driven consumer engagement

The growing popularity of mobile technologies and applications, lead many companies to develop relations with consumers through mobile applications. Therefore, it is important to understand how to design applications based on consumer preferences. This research seeks to understand which features of mobile applications stimulate consumer engagement and lead to continuous use of mobile applications. This study used an online questionnaire to collect data from 246 respondents. The data was analyzed making use of Structural Equations Modeling (SEM). The results indicate that perception of such features as design solutions and information quality will result in higher engagement leading to continuous usage of mobile applications. Moreover, consumer engagement positively influenced users’ intention to continuous usage of mobile applications. Inconsistent with expectation, consumer interaction and functionality features are not found to be positively related to consumer engagement with mobile applications.     

大型CDMA网络中移动IP技术应用和部署策略研究

近年来随着互联网和移动通信的高速发展,人们对移动业务如语音、视频、互联网访问、游戏、定位等提出了更高的要求.在新的市场竞争环境、新业务发展和新技术促进下,运营商将高带宽移动接入和基于互联网的服务结合起来.在提高无线频率利用效率的同时,为用户提供更经济、内容更丰富的无线数据业务和移动增值业务.本文对CDMA分组域组网的网络参考模型进行研究.提出了部署移动IP的策略.     

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.     

Enhancing IP service provision over heterogeneous wirelessnetworks: a path toward 4G

Second-generation mobile radio systems have been deployed successfully worldwide and have evolved to higher data rates and services. Third-generation mobile radio systems are currently starting to be developed in different regions of the world. Today, the open question is how the third-generation systems will evolve. It is very likely that fourth-generation systems will not be a single standardized air interface, but a set of different technologies and standards. In particular, wireless LAN/wireless PAN type systems are designed for high/medium-data-rate access, low range, and, in general, low mobility. They are applicable to corporate networks and public access as a complement to cellular mobile radio systems for hot spot applications such as airports, hotels, and campuses. In this specific WLAN/WPAN framework and to guarantee an agreed QoS provision over such infrastructures, we propose a solution based on the wireless adaptation layer approach. In particular, aspects related to wireless link impairments and traffic requirements are approached by the implementation of configurable, modular software that is adapted to the specific conditions and needs of the particular wireless infrastructures     

Challenges in the migration to 4G mobile systems

With the rapid development of wireless communication networks, it is expected that fourth-generation mobile systems will be launched within decades. 4G mobile systems focus on seamlessly integrating the existing wireless technologies including GSM, wireless LAN, and Bluetooth. This contrasts with 3G, which merely focuses on developing new standards and hardware. 4G systems supports comprehensive and personalized services, providing stable system performance and quality service. However, migrating current systems to 4G presents enormous challenges. In this article, these challenges are discussed under the headings of mobile station system, and service aspects. Proposed solutions to the research problems in each aspect are also examined.     

Wireless Future Based on Fiber

When a whole area is provided with a FTTH network for consumer communication and entertainment services it opens up a variety of possibilities and opportunities for wireless services to add connectitivity and services in the market place. Always-on connection radically change the way consumers access and work with information. This is becoming evident in markets with high penetration of high bandwidth alwas-on services such as Iceland, where about 85% of households have an Internet connection and over 60% of all households have a DSL connection for their Internet usage. When enjoying such rich connectivity in the home and workplace, the market will demand the same access to their data and services when mobile. Gudmann B. Birgisson, BSc International Marketing, Project Manager at RE's Fiber Utility. Former marketing and product manager for consumer ISP services at Siminn (Iceland Telecom). Has experience in development and marketing of ISP and content services to the consumer market. Jonatan S. Svavarsson, MSc Mechanical and Management Engineer, Director for RE's Fiber Utility. Former PriceWaterhouseCoopers consultant and partner. Has experience in management and consulting icelandic companies in an international environment.     

Mobile computing and ubiquitous networking: concepts, technologies and challenges

With the rapidly increasing penetration of laptop computers, which are primarily used by mobile users to access Internet services, support of Internet services in a mobile environment become an increasing need. The opportunities emerging from these technologies give rise to new paradigms such as mobile computing and ubiquitous networking. However, there are numerous challenges such as reliability and quality of service, infrastructure costs, energy efficiency of mobile devices, among others. This paper analyzes concepts, technologies and challenges related to these paradigms. The major challenges include mobility, disconnection and scale, new information medium and new resource limitations. As a fundamental characteristics of mobile environments, the user can see the same computing environment regardless of his or her current location. The most exciting promises of mobile computing and ubiquitous networking stay an entire new class of applications and potential new massive markets combining personal computing and consumer electronics.     

Compact multidimensional broadband wireless: the convergence of wireless mobile and access

Broadband wireless communications have gained increased interest during the last few years. This has been fuelled by a large demand on high-frequency utilization as well as a large number of users requiring simultaneous high-data-rate access for the applications of wireless mobile Internet and e-commerce. The convergence of wireless mobile and access will be the next storm in wireless communications, which will use a new network architecture to deliver broadband services in a more generic configuration to wireless customers, and support value-added services and emerging interactive multimedia communications. Large bandwidth, guaranteed quality of service, and ease of deployment coupled with the great advancements in semiconductor technologies make this converged wireless system a very attractive solution for broadband service delivery.     

An outlook on the evolution of mobile terminals: from monolithic to modular multiradio, multiapplication platforms

Terminals, including traditional cellular phones, have historically been optimized for a small number of services over a specific network. With the convergence of consumer electronics and Internet-based services, voice and video are now being offered on a variety of access networks, and many functions are being combined into single devices. In addition to new sophisticated audio/video coding and graphics capabilities, there is a growing demand for cheap and ubiquitous broadband wireless Internet access. This demand is driving the need for multiradio platforms that include new licensed and unlicensed air interface technologies, such as WLAN, UWB and Wimax. The proliferation of new applications and wireless standards has created the need for a dramatic change in the portable/mobile terminal architecture. This paper presents an overview of the evolution of mobile terminal architectures, from monolithic to flexible, modular, and capable of meeting the increasing demand for an ever larger number of features at the right cost and time to market.     

Low-latency mobile IP handoff for infrastructure-mode wireless LANs

The increasing popularity of IEEE 802.11-based wireless local area networks (LANs) lends them credibility as a viable alternative to third-generation (3G) wireless technologies. Even though wireless LANs support much higher channel bandwidth than 3G networks, their network-layer handoff latency is still too high to be usable for interactive multimedia applications such as voice over IP or video streaming. Specifically, the peculiarities of commercially available IEEE 802.11b wireless LAN hardware prevent existing mobile Internet protocol (IP) implementations from achieving subsecond Mobile IP handoff latency when the wireless LANs are operating in the infrastructure mode, which is also the prevailing operating mode used in most deployed IEEE 802.11b LANs. In this paper, we propose a low-latency mobile IP handoff scheme that can reduce the handoff latency of infrastructure-mode wireless LANs to less than 100 ms, the fastest known handoff performance for such networks. The proposed scheme overcomes the inability of mobility software to sense the signal strengths of multiple-access points when operating in an infrastructure-mode wireless LAN. It expedites link-layer handoff detection and speeds up network-layer handoff by replaying cached foreign agent advertisements. The proposed scheme strictly adheres to the mobile IP standard specification, and does not require any modifications to existing mobile IP implementations. That is, the proposed mechanism is completely transparent to the existing mobile IP software installed on mobile nodes and wired nodes. As a demonstration of this technology, we show how this low-latency handoff scheme together with a wireless LAN bandwidth guarantee mechanism supports undisrupted playback of remote video streams on mobile stations that are traveling across wireless LAN segments.     

Voice access of global information for broad-band wireless:technologies of today and challenges of tomorrow

The rapid development of the Internet and the World Wide Web has created a global network that will soon become a physical embodiment of the entire human knowledge and a complete integration of the global information activities. The traditional approach to access the network is through a computer physically tied to the network. As broad-band wireless takes off, the traditional tethered approach will gradually become obsolete. It is believed that one of the most natural and user-friendly approached for accessing the network will be via human voice, and the integration of spoken language processing technologies with broad-band wireless technologies will be a key to the evolution of a broad-band wireless information community. This paper offers a vision of the above concept. Technical considerations and some typical example applications of accessing the information and services using voice in a broad-band wireless environment are discussed. Fundamentals of spoken language processing technologies that are crucial in such a broad-band wireless environment are briefly reviewed. Technical challenges caused by the unique nature of wireless mobile communications are also presented along with some possible solutions     

A quality-aware VoWLAN architecture and its quantitative evaluations

The deployment of wireless LAN and other communication media, such as 3G cellular, is proceeding rapidly. In the near future, multiple WLAN carriers, together with 3G cellular and other communication carriers, will provide their services in a complementary fashion. Furthermore, next-generation mobile phones, which may use voice and data services simultaneously, will connect these networks. In the present article we design and evaluate a new network architecture that ensures appropriate QoS for next-generation mobile phones. Through performance evaluations, we show that our architecture improves QoS for voice communication.     

BRAIN—an architecture for a broadband radio access network of the next generation

The tremendous growth rates of the Internet as well as the area of mobile communications give rise to the chance that the mobile Internet is most promising by combining both the Internet and mobile communications. These prospects are the motivation for the European research project BRAIN (Broadband Radio Access for IP‐based Networks), which is developing an open architecture for a broadband wireless mobile access network offering an integrated communication platform across heterogeneous networks and, thus, goes beyond current third generation systems and towards the mobile Internet. The project covers three major technical areas: support of seamless service provision in a mobile environment; the design of an IP‐based access network that will support non‐cellular technologies such as wireless LANs; and requirements of a broadband air interface suitable for hot spots. BRAIN is going to integrate HIPERLAN/2 with UMTS by means of an IP access network. The work is guided by a user‐centric top‐down approach ensuring that user functionality is the key driver of the project. This article will focus on that part of the BRAIN work which specifies the main interfaces of the BRAIN architecture and deals with aspects related to the support of Quality of Service and mobility. Copyright © 2001 John Wiley & Sons, Ltd.     

从WAP的应用看移动因特网的发展

ＷＡＰ技术的开发与应用揭开了移动因特网发展的崭新一页,据预测,到２００４年亚太地区移动用户数将达到３．７亿,其中移动数据用户将占１．６亿;移动电子商务市场也将于２００３年超过固定电子商务市场。移动互联网未来的热点包括企业网的无线应用、与位置相关的服务以及移动电子商务。     

无线局域网中异步数据传输模式及其管理

无线局域网将成为移动计算机用户互联网的主要手段，ＩＥＥＥ８０２．１１是其正发展中的标准，许多新技术在不断充实着该标准，本文主要介绍了８０２．１１无线ＬＡＮ中基于ＣＳＭＡ／ＣＡ协议的异步数据传输模式及其管理，同时也讨论了避免碰撞，吞吐量及隐藏终端等相关问题。     

Multicasting streaming media to mobile users

Content distribution in general, and multicasting in particular, over a wired network to static hosts can be realized by placing proxies and gateways at several parts of the network. However, if the end hosts are mobile over heterogeneous wireless access networks, one needs to consider many operational issues such as network detection, handoff, join and leave latency, and desired level of quality of service, as well as caching and load balancing. This article surveys a set of protocols and technologies that offer multicast-based services for streaming multimedia in a mobile environment. It also brings forth some of the issues related to mobile content distribution in the wireless Internet that may be helpful during its deployment by application service providers.     

A view of telecommunications network evolution

While deployment of new network technologies has not been steady over the years, it is useful to take a long-term view of how major new telecommunications infrastructures evolve. Since the beginning of this decade, we have witnessed the emergence of new generations of three major communication networks. This article addresses the market conditions, technology innovations, and services driving the need for intelligent all-optical, 3G wireless, and QoS-based packet networks. Market forces such as traffic and subscriber growth, equipment cost reduction, and new technology penetration have a deep impact on network buildouts. Technology innovations abound, especially in the optical domain. For example, Raman amplification, pure optical switches, and tunable lasers have had a major impact on the architecture of optical networks. Many key services, such as streaming audio and high-quality image transfer, were not possible using wireless access because of its limited bandwidth and performance. With 3G wireless technology, a true mobile Internet will become a reality. Businesses have shied away from the use of the public Internet because of service quality. Thanks to advances in MPLS and service intelligence, this is expected to change. For each type of network, we survey the key factors shaping its evolution and implications on network architectures.     

The role of Internet technology in future mobile data systems

Mobile telephony and the Internet are the fastest growing businesses in the telecommunications market. This is why most operators and service providers are looking after the development of new services in both sectors, and newcomers are expected to enter the arena. The mobile operators foresee an increasing share of their revenues coming from new data services, while Internet service providers are attracted to wireless technology and mobility services both to reduce costs within the last-mile segment and to enrich their market share, providing ubiquitous access to the Internet and corporate intranets. In this scenario several wireless overlay networks will coexist, and their interworking will be a challenging objective. The employment of Internet technology, with its novel mobility and security extensions, seems to be the most attractive option for achieving that goal. In addition, the migration to a full IP network architecture, even within each specific wireless domain, will be another promising opportunity, already under consideration within several technical and standardization bodies. The envisioned role of Internet technology makes it worthwhile to undertake significant research efforts on the development of innovative IP-based mobile data systems, and opens promising opportunities for both telcos and Internet service providers.     

Interworking techniques and architectures for WLAN/3G integration toward 4G mobile data networks

The intense wireless LAN standardization and R&D activities worldwide, combines with the recent successful deployment of WLANs, provide prime evidence that WLAN technology will play a key role in the fourth generation of mobile data networks. In this context, there is a strong need to integrate WLANs with 3G mobile data networks and develop hybrid mobile data networks capable of ubiquitous data services and very high data rates in strategic locations. This article addresses this need by proposing and discussing some novel architectures able to provide internetworking between WLAN and 3G networks, and meet the requirements of the most common internetworking scenarios. These architectures can enable 3G subscribers to benefit from high-throughput IP connectivity in hotspots and also to attain service roaming across several radio access technologies, such as IEEE 802.11, HiperLan/2, ULTRAN, and GERAN.