Wireless Networks and Technologies in the Third Generation Era

Wireless Networks and Technologies in the Third Generation Era

Mohammed O. Zaatari

Significant developments are underway in wireless communications to enhance existing Second Genera-tion (2G) wireless networks to enable delivery of high bit rates to wireless terminals. Third Generation (3G) technologies offer the promise of Internet connectivity, video conferencing, and worldwide roaming in a small handheld terminal. This paper provides an overview of 3G technologies, starting with a review of technology proposals and standards activities. It then describes a proposed vision of the advanced network with emphasis on key service and applications drivers. In the process, we focus on the current vendor developments and corporate alliances especially related to the development of wireless Internet Protocol (IP) applications. The paper concludes with a presentation of a phased approach to the deployment of a mobile corporate network.

Introduction

Wireless communications constitute the fastest growing segment of the communications industry today. In 1995, cellular communica-tions systems worldwide listed fewer than 100 million subscribers, with an average of 150,000 new ones joining each day. The demand for enhanced voice and data services stretched the limits of first generation networks. Second-generation (2G) wireless networks provided additional services that included fax, voice mail, call waiting, caller ID, limited short message capability, and improvement in network capaci-ty. 2G networks also allowed the capability of transmitting circuit switched asynchronous and packet data at a raw rate of up to 9.6 kb/s or 14.4 kb/s. Today, with the exponential growth of the Inter-net, the mobile market is stretching the technology still further. Market research studies show that more wireless users are demanding Internet capabilities equivalent to those provided by the fixed network. As shown in Figure 1, subscribers want the Internet and they want wireless even more.

Satisfying this demand requires development of a wireless network that supports advanced services previously available only through high-speed wired networks. The concept of 3G is based on the global International Mobile Tele-communications (IMT-2000) initiative spon-sored by the International Telecommunications Union (ITU) to create a unified global set of

standards that will lead to commercial deploy-ment of advanced wireless services. The IMT-2000 goals and objectives for 3G are as follows:

Reduce telecommunications performance gap between wireless and existing fixed networks

Convergence across technologies and geogra-phic boundaries

Operate in both satellite and terrestrial envi-ronments

Coexistence with 2G systems

The main requirement which applies to 3G systems is to support higher data rate packet-switched (Internet Protocol (IP) traffic) and circuit switched (voice and video traffic) service up to at least 384 kb/s in all radio environments and up to 2 Mb/s in low mobility and indoor environments. The high bit-rate data services will not only allow packages of multimedia services (e-mail and Internet access, video conferencing, and imaging capability), but also deliver them seamlessly across heterogeneous networks to highly mobile terminals.

While much of the ITU 3G focus has been on efficient access air interfaces, the design of a true multimedia capable network will most probably include a role for IP-based networking and appli-cations in the new world. Convergence towards a combined circuit and packet switching infra-structure is another significant requirement in the deployment of 3G networks. This paper will consider developments in both components to

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enable mobile users to access the fastest overall bandwidth and at the same time provide a

Source: ITU-IMT2000 Workshop, New Jersey, November 10-11, 1998

Figure 1. Mobile and Internet Subscriber Actual and Projected Growth

smooth transition from current circuit switched backbone networks to packet based unified networks.

The focus of this paper is not so much on the technical details. The interest is in presenting the vision for the evolving technology. The first section starts with a technology survey of the different proposals under consideration. The second section peaks into the standardization activities and is followed by a section on the proposed government spectrum allocations. We lay out the vision for 3G services next and follow with highlights of the terminals, appli-cations, and complementary initiatives that will be used in the delivery of 3G services. The paper concludes with a two-phased approach for Information Technology (IT) managers for a smooth transition and deployment of the new services as they develop and mature.

Technology Proposals

While there are several co-existent 2G standards in place today, there is no single worldwide wire-less standard. This has created several incompa-tible regional standards (see Table 1). Ideally these standards will converge into a single wire-less standard thus ending compatibility problems and roaming limitations. The ITU is attempting to determine a global umbrella standard for terrestrial, mobile, and satellite-based systems. In the process, the ITU has received 16 proposals for Radio Telecommunications Technologies (RTTs): 10 terrestrial and 6 satellite proposals. The satellite

proposals are outside the scope of this paper and will not be discussed. Virtually all proposed terrestrial RTTs are based on Direct Sequence Code Division Multiple Access (DS-CDMA) wireless technologies. Time Division Multiple Access (TDMA) will emerge in the 3G era as an evolution of the Interim Standard (IS)-136. Table 2 includes a summary of the characteristics of the three major proposals. [1,2,3,4,5,6,7,8]

Standardization Activities

Ericsson and Qualcomm have been leading two separate camps in the debate relating to the two CDMA standards. In March, Ericsson and Qualcomm agreed on a far-ranging settlement of their long-running dispute over CDMA patents. The agreement included cross licensing of CDMA Intellectual Property Rights (IPR), Ericsson’s purchase of Qualcomm’s infrastruc-ture business, and a decision to coordinate activi-ties at the ITU. As a consequence, a broad con-sortium of operators referred to as the Operators’ Harmonization Group (OHG) defined a harmon-ized tri-mode code standard and submitted the proposal to the ITU for discussion in June 1999. The three modes include a direct sequence mode with a single carrier operation compatible with Wideband CDMA (W-CDMA), a multi-carrier mode compatible with CDMA-2000, and a Time Division Duplex (TDD) mode of operation. Global roaming will be achieved not by a single, ubiquitous standard, but by multi-mode handsets. OHG memberships include several US vendors and operators.

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At the moment, the ITU direction is that the harmonization efforts will rest with the wireless

First Generation Networks Second Generation Networks 30 KHz Radio Channels Frequency Division Multiple Access

(FDMA) Method Analog Modulation Scheme Standards: Advanced Mobile Phone Service

(AMPS) Cellular Data Packet Data (CDPD) is the

only data capability Capacity Reached a Brick Wall as Network

Evolved

30 KHz (or 200 KHz for GSM) Radio Channel TDMA or CDMA Method Digital Modulation Scheme Better Voice Quality Characteristics Dual Mode Operation in the Cellular band (800

MHz); analog is default common denominator TDMA and CDMA are incompatible Digital-only schemes (TDMA or CDMA) in

Personal Communications Services (PCS) Band (1900 MHz)

Low Data Rate Capability (9.6 kb/s - 14.4 kb/s) Capacity Improvements:

TDMA - US (IS-4 & IS-136): 3 X AMPS TDMA - Europe Global System for Mobile

(GSM): 8 X AMPS CDMA - US (IS-95): up to 10 X AMPS

Table 1. Characteristics of First and Second Generation Wireless Networks

3G Standard Characteristics

Wideband CDMA (W-CDMA)

CDMA-based technology Sponsored by GSM operators 5 MHz Radio Channel Data Rate Capability (384 kbps to 2 Mbps)

CDMA2000 CDMA-based technology Sponsored by IS-95 operators 1 X 5 MHz Radio Channel or N X 1.25 Radio Channels Data Rate Capability (384 kbps to 2 Mbps)

Universal Wireless Communications (UWC-136)

TDMA-based technology Compatible with IS-136 and GSM 200 kHz Radio Channel or 1.6 MHz Radio Channel Data Rate Capability (384 kbps to 2 Mbps)

Table 2. Characteristics of 3G Technology Proposals

carriers. Consequently, the Harmonization Agreement is slated for approval by the ITU in December 1999. The ITU final recommendation will also include a separate migration path for TDMA carriers along the Universal Wireless Communications (UWC)-136 proposal. This umbrella approach clearly defeats the goal of worldwide compatibility. To receive truly global coverage, callers will carry expensive multi-mode handsets incorporating the different technologies. The Global Systems for Mobile (GSM) Mobile Application Part (MAP) and IS-41 American National Standards Institute

(ANSI) interoperability promises to be a sticky issue that requires resolution. In all the ITU discussions so far, the network backbone has been ignored in all the talk about 3G technologies. With the strong belief that the wireless Internet is the 3G application, plugging 3G into the IP network is an essential ingredient of the advanced wireless technologies. A new focus group was recently established — 3G.IP — to tighten the link between wireless technologies and IP. The goal of 3G.IP is to make sure the worldwide standards groups build IP hooks into now evolving 3G technologies. The group will also attempt to bridge the gap


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now dividing European and North American carriers by hammering out a single standard to govern how IP services will be transported over 3G systems. The conviction is that a single standard will go a long way to convince tele-communications and IT managers to become an integral part of an enterprise’s data infrastruc-ture. The focus group expects to have some interim standards established by the end of 1999 that include both circuit switched and packet data elements. The end of 2000 should finish a com-plete set of IP network standards, with network trials in 2001.

Standardization efforts for IP security protocols are also significant for the deployment of 3G services. In particular, IP Security (IPSec) can provide the authentication and encryption algorithms to address security concerns for wireless 3G services. IPSec was developed by the Internet Engineering Task Force (IETF) as a set of protocols that offered IP security features within IP version 6. The same set of protocols can also be used to make regular IP traffic (version 4) more secure. With the blending of 3G and IP, IPSec can provide the security services to encrypt and authenticate data that is

transmitted over the 3G network. IPSec also makes use of digital certificates to provide a more robust way to authenticate 3G terminals. The IPSec standard was ratified by the IETF in November 1997. Interoperability tests have not yet been conducted; however, in the 3G time, IPSec gateways from different vendors are expected to interact with each other.

3G Spectrum Allocation

With the ITU finalizing the 3G standards, the individual governments are left with the respon-sibility of developing 3G licensing policies. The radio regulations (RRs) of ITU are updated in the World Administrative Radio Conference (WARC). The next WARC is scheduled for May 2000. Table 3 summarizes existing and forecasted spectrum requirements and Figure 2 illustrates the use of the 3G frequencies in different regions as identified in the WARC-1992 Conference.

It is not clear at the moment where the majority of additional spectrum will come from. The Federal Communications Commission (FCC),

RegionTotal 3G Spectrum

Existing Mobile Terrestrial Allocation

Forecasted Additional Spectrum

(MHz) (MHz) (MHz)Americas 390 230 160Europe 555 395 160Asia 480 320 160

Table 3. Summary of Global Mobile Terrestrial 3G Spectrum Requirements in 2010


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Figure 2. WARC-1992 IMT2000 Frequency Allocationsunder Congress’ 1997 Budget Act, is required to auction 40 MHz of spectrum in the 2110 MHz to 2150 MHz band plus an additional 15 MHz from the 1990 MHz to 2110 MHz. The FCC is contemplating reserving the spectrum for 3G. Other frequencies considered by the FCC lie in the 1710 MHz to 1755 MHz band. This spec-trum is occupied today by government opera-tions, but will be turned over to non-government operations possibly by the time operators deploy 3G services. Other options include another 84 MHz currently allocated for UHF television providers. TV operators are supposed to free this spectrum by 2006 as they convert from analog to digital services. In a paper issued on March 29, 1999, the FCC indicated that it might not aggres-sively seek more 3G spectrum at WARC-2000. Final allocations are not expected before the end of 2001. It is important to note that in the US, cellular and Personal Communications Service (PCS) licenses have full freedom to use whatever technologies they want to use. US operators will not need FCC permission to implement the 3G standards onto the existing spectrum.

While the FCC is taking a wait-and-see attitude before jumping into the 3G licensing foray, regu-lators from Europe and Japan have been busy crafting licensing policies that will determine the success of 3G networks in their markets. The European Union is requiring member states to approve licensing scheme by January 1, 2002, recent activities show faster allocation schedules. Finland has already awarded four 3G licenses and the United Kingdom is slated to auction five licenses, with the largest portion of available radio expected to be awarded to a new market entrant. The German regulatory agency is lean-ing towards auctions and award licenses for at least two new players this fall. Japan will prob-ably be implementing 3G by the end of the year 2000.

3G Services

The main appeal of wireless is the mobility dimension. It offers a user the convenience of conducting business from anywhere at any time. Approximately 48 millions U.S. workers have jobs that require them to be mobile much of the time. With 2G systems, slow data rates have discouraged the development of wireless data

services that will help this mobile workforce to successfully compete in the information age. The higher data rates promised by 3G technolo-gies will play an important role in enabling mobile operators to offer a broader range of services. Categorically, the following 3G services are identified:

Voice services will remain an important application for users and a source of revenue for network operators.

Low data rate services will allow existing messaging services (including e-mail, fax, and voice mail) to evolve into a unified plat-form. Users will require communicating in the medium of their choice regardless of how other users are communicating. For example, a user will respond to a fax mes-sage with an e-mail message including a file attachment.

Medium data rate services for file transfer and remote Local Area Network (LAN)/ Intranet access. Services are manifested as client applications connected to a specific access networks.

High data rate services and multimedia services will help bring in an abundance of Internet, realtime audio/video, and special-ized wireless business services. These services will be flexible to accommodate variable Quality of Service (QoS) parame-ters (i.e., delay, data rate, and voice quality).

In the 3G era, mobile users will achieve relative-ly continuous connectivity using various voice, data, and video services through different net-works and devices. Subscribers will always be connected to some network with some device, but not necessarily a single device (at least with-in the next five years). The connectivity will not equate with bandwidth and the available band-width may vary drastically as a subscriber moves from one network to another. The implementa-tion involves many factors that will contribute to the ultimate adoption of 3G services. Availabil-ity of end user devices, development of killer applications, significant data initiatives in proto-col and software design, and operator and equip-ment vendor commitments will facilitate the commercialization of 3G services.

Future 3G Terminals


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As a first step toward understanding the design requirements of 3G terminals, we first take a brief look at the various handheld smart phones or Personal Digital Assistants (PDAs) that have been announced for availability this year. A few of the products are sampled in Table 4. With the exception of the Palm VII, the devices combine a PDA with a mobile phone.

The 3G wireless terminals of the future come in diverse forms with a variety of specialized functions, and not just hybrid phone-plus-PDA-type devices. The terminals will have a common core of hardware and software functionality embedded in them. An embedded single chip will provide the computation, protocol, and communications processing capability needed for ubiquitous wireless interworking. In conjunction with these common core set of functions, 3G terminals shall be capable of full desktop functionality including adequate displays, good mechanisms for editing and viewing, and quick boot features. Key design requirements need to be addressed by current technological developments for 3G services to achieve their full potential. [9] The challenges presented include energy efficiency, auto config-uration, adaptivity, re-configurability, and location and context awareness. Security, user interfaces, and appropriate partitioning of appli-cation functions between a wireless terminal and

the network infrastructure also need to be consid-ered in the context of future 3G terminals. In the next five-year horizon, there will not be a single terminal. Beyond the five-year horizon, two camps are emerging on the question of whether the ultimate wireless multimedia device will be integrated or modular. The evolving 3G-business model, which emphasizes a broad spectrum of consumers to business users, seems to favor modular devices (notebook PCs, PDAs, and portable computers, or smart phones) with built-in 3G wireless communications. Some people will want their data integrated into their phone, but others would rather have it in a palm PDA or similar device. However, it is too early at this stage to rule out a 3G wireless terminal that integrates a myriad of wireless terminals in a single package.

3G Applications

In today’s 2G systems, the wireless data industry began its development through vertical applications. The applications were developed to support the needs of professionals in particular industries. As 3G systems emerge, the question is about wireless applications. Obviously, Inter-net data would be an absolutely essential applica-tion (and maybe the killer application) for the 3G technology. IP utilizes open server platforms

Product Name and Vendor

Features i1000+Communicator

9000SCH-3500 Palm VII R380 pdQ

Vendor Motorola Nokia Samsung 3COM Ericsson QualcommFeaturesBasic Voice x x x x xCaller ID x x x x xE-mail x x x x x xFax x x xMessaging x x x x xNote Taker x x x xOrganizer x Voice only x xScheduler x x xWeb Browser WAP WAP WAP x WAP AP

Service Partner Variable

Geoworks Wireless Content

& ServicesVariable Bell South Variable Variable

Technology iDEN GSM CDMATech.

IndependentGSM CDMA

Price$1,000 - $1,200

$1,000 - $ 1,200$1,000 - $1,200

$800 $1,000 – $1,200

$1,000 - $1,200

iDEN is a GSM-adapted technology developed by Motorola. Nextel is Service Provider in the U.S.


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Table 4. Samples of Early 3G Terminalsand off-the-shelf software that offers improved price performance and facilitates the rapid deployment of 3G services. Several complimen-tary technologies are key enablers for 3G IP applications and are discussed in the next section.

3G applications will cut across different indus-tries. 3G terminals are required to extend corporate information services to the mobile workforce (e.g., field sales). Horizontal applica-tions, such as e-mail and Intranet access, will contribute to increased productivity. The appli-cations will provide localized and personalized information that is pushed to mobile profession-als so that they can quickly act on the informa-tion. In principle, wireless applications are similar to their wireline counterpart. The only difference is the communications physical layer. Wireless IP is not just another Wide Area Net-work (WAN) connection. The wireless physical layer has lower bandwidth and exhibits higher latency, higher and burstier error rates, and a much higher probability of failure. This presents a potentially crippling effect on client/server applications.

A wireless middleware layer implemented on a mobile proxy server provides the solution. The mobile proxy server comprises a client, which runs on the mobile 3G terminal, and a server which accesses back end services as shown in Figure 3. Client/server communications use special wireless protocols over the wireless links; and the proxy server employs conventional LAN/WAN protocols to reach back end services. [10,11,12]

Complementary 3G Initiative

Several (separate but parallel) multi-vendor industry development programs that are under-way provide an additional impetus to develop-ment of 3G. The programs enable promising and integral applications to support both the func-tionality and intelligence defined in the 3G client/server architecture. Most importantly, major industry players support them.

Wireless Applications Protocol (WAP)

WAP provides a set of open standards that let 3G terminals such as smart phones or handheld computers browse content on the Web. In the

Figure 3. 3G Client Server Architecture

WAP system, a gateway is placed at an IP access point for the WAP client (3G terminal). The gateway acts as a translation conduit between Web sites and WAP-enabled clients. The client is thus able to access Web-based information in a stripped down format, with minimal graphics and text optimized for the smaller displays of 3G terminals. The format conversion from Hyper-text Markup language ( HTML) into Wireless Markup Language (WML) can either be per-formed at the service provider or at the gateway.

Current WAP specification version 1.1 imple-ments enhanced protocol layering to adapt to the wireless environment. The layers include session, transaction, security, authentication, and data transport layers. Complete specification is provided at the WAP Forum Web page (http:// www.wapforum.org). [13]


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Wireless Knowledge

Wireless Knowledge (WK) is a 50-50 jointly owned company between Qualcomm, Inc. and Microsoft Corporation. The service seeks to deliver information services using wireless data capabilities via outsource network operations center approach. The initial focus will be corporate users, then Small Office/Home Office (SOHO) users. Qualcomm and Microsoft have undertaken the construction of an operations center that will provide the new wireless services and related support devices to make it easier for corporations to embrace wireless connectivity. In this sense, customers are immune from their applications being outdated. This is especially valuable in the early stages of 3G technology development. Miscellaneous white papers and current product offerings are available at the Wireless Knowledge Web site. [14]

Bluetooth

Bluetooth, backed by Nokia and Ericsson, in concert with Intel, IBM, and Toshiba, is aimed at developing a system for short range, low power wireless communications and synchronization between mobile phones, PCs, PDAs, printers, scanners, fax machines, cameras, headsets, keyboards, or virtually any other digital device. It promises “cableless” connections between the different devices using the 2.4 GHz frequency band. Frequency-hopping techniques keep communications flowing even in noisy environ ments and maintain an RF link between devices that transfer data as needed. The RF links hops across its 79 sub-channels at the blazing rate of 1600 hops/sec. This fast hop rate means that different Bluetooth networks could operate in the same vicinity. Distance is limited to 10 meters. [15]

3G Smart Phone Operating Systems: Symbian and Microsoft Windows Compact Edition

Symbian is a joint venture between Nokia, Ericsson, Motorola, and Matsushita, as well as software developer Psion PLC. EPOC is the name given by the Symbian consortium to its 32 bit operating system targeted for use with smart phone and handheld PCs. Symbian seeks to develop an open standard for 3G terminals with network-based data applications by separating

the operating system and middleware from the user interface, terminal vendors, or carriers and can develop customized user interfaces and applications. Symbian’s operating system EPOC competes with Microsoft’s Compact Edition (CE) opera-ting system. Windows CE is assuming the role originally seen for handheld PCs. The operating system with a suite of applications that are actu-ally scaled down versions of the major Microsoft Office programs. It supports rich content e-mail functionality with the Pocket version of Outlook and comes complete with a calendar, contact list, and task list. It performs spell checks, changes font and formatting options, password-protects documents, and prints documents.

Wireless Portals

These days, wireless portals have been rolling out limited services that push stock updates, sports reports, door-to-door directions, and other information to terminals. In the future, interac-tivity is expected as an additional service, allow-ing customers to respond to messages, perform simple transactions, and surf the Web. Portals will offer wireless versions of the existing Web sites. Wireless portals will be making specific deals with content providers. Wireless portal will also team up with a wireless network opera-tor to integrate the wireless portal’s database with the user location databases of the wireless network. This delivers real time information services that mobile workers want.

Mobile IP

IP and its companion protocol Transmission Control Protocol (TCP) will play a big role in the deployment of 3G data services. One of the principal challenges in applying TCP/IP to a mobile-wireless environment is accommodating the user’s IP address. The IP address is a fixed address designed to identify the point of attach-ment of the 3G terminal to the specific corporate sub-network. Given that a mobile professional roams among several networks, some technique is needed to properly identify the roaming 3G terminal as it attaches to a different network. Mobile IP enhances the conventional IP protocol to support roaming of nodes wherein the 3G terminal can receive datagrams no matter where they are located. [16] Mobile IP introduces new security vulnerabilities to network operations.


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IETF documents address the security concerns. [17,18]

Conclusions

Starting in 2003, 3G wireless systems deployed in the US will offer higher speed data services. The bandwidths will allow for IP-based multi-media services over wireless access. The com-bination of Internet connectivity and mobility creates the conditions where wireless technology becomes an important factor in the enterprise network.

Most IT organizations have not been confident about wireless technologies and still do not have strategies for dealing with the new technology. The uncertainty is based around the newness of the technology, concern over end-to-end trans-action security, how users will respond to the new devices, and the complexity of working with external content and service suppliers. The exciting thing today is that the foundation of 3G services has already been laid. There are exis-ting organizations soon will be companies founded solely to take advantage of the new platform.

While wireless networking is not going to be viewed as a replacement for wireline in the foreseeable future, wireless access and mobile connectivity to corporate resources is mission critical in the face of increasingly mobile profes-sionals. It is time that a corporate IT managers define an evolution path to the “Wireless Office” which enables mobile users to get con-nected to the enterprise resources. A phased approach guarantees a winning strategy in the develop-ment of the Wireless Office. The initial phase of a pilot project presents a low investment option. At each stage of the evolution process, the IT managers will have the ability to measure the additional costs and evaluate the benefits.

In identifying the first phase, the IT managers are evaluating their customers’ requirements for mobility and examining the business benefits of implementing corporate mobility. The results of the first phase will help to articulate their target audience needs, determine their needs, make sure they are met, and prioritize the areas that present the biggest opportunities. At the conclusion of the first phase, the IT managers should have developed the key messages and are now ready

to get the message out in the form of an imple-mentation strategy that will meet their goal.

The implementation strategy involves the tackling of all the issues and overcoming the challenges of wireless networking. During the second phase, the IT managers evaluate the pros and cons of the technologies, techniques, and initiatives that achieve their goals. The health and security dimensions of mobile networking are tackled at this stage. In the process, the network managers are assessing the extent to which all the alternative technologies will meet both the user’s requirements and the manage-ment of the corporate network. The final phase of the analysis defines the criteria for determin-ing the most effective solution. Examples of real time experiences from other early adopters are also quite valuable. At this stage, the IT mana-gers are ready with an implementation plan for the pilot.

The pilot phase is the first step in moving some of the corporate users to the mobile environment. This phase includes evaluating and examining the following:

Added benefits of corporate mobility (e.g., enhanced communications, simplified logistics for company re-organizations)

Effect on traffic profile, telecommunications costs, and company culture

Main corporate network applications used for mobility

Whether the mobile solution can truly compete with wired connections in terms of both performance and cost

The final stage of full corporate mobility is achieved when the benefits of mobility are evalu-ated in the context of answering the following questions:

How to approach technology and product selection

How to gain maximum business value from the current mix of 3G technology, services, and applications

How the 3G will evolve in the next five years

The answers to the last three questions may not prove an easy task. The reader can use this report as a first step into a promising and yet evolving technology.


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References

1. Presentation Slides, IMT2000 Workshop, New Jersey, November 10-11, 1998.

2. International Telecommunications Union: http://www.itu.int/imt/

3. The Telecommunications Industry Associa-tion: http://www.tiaonline. com

4. Pandya, R., et al., “IMT-2000 Standards: Network Aspects,” IEEE Personal Commu-nications Magazine, August 1997.

5. Qualcomm White Paper, “The Technical Case For Convergence of Third Generation Wireless Systems Based on CDMA — Five Technical Principles to Consider,”: http:// www.qualcomm.com.

6. Knisely, D.N., et al., “Evolution of Wireless Data Services: IS-95 to cdma2000,” IEEE Communications Magazine, October 1998.

7. Ojanpera, T., et al., “An Overview of Third Generation Wireless Personal Communica-tions: A European Perspective,” IEEE Pers-onal Communications Magazine, December 1998.

8. Ojanpera, T., et al., “An Overview of Air Interface Multiple Access for IMT-2000/ UMTS,” IEEE Communications Magazine, September 1998.

9. Lettieri, P., et al., “Advances in Wireless Terminals,” IEEE Personal Communica-tions Magazine, February 1999.

10. Fasbebder, et al., “Any Network, Any Terminal, Anywhere,” IEEE Personal Communications Magazine, April 1999.

11. Chan, M., et al., “Next Generation Wireless Data Services: Architecture and Experi-ence,” IEEE Communications Magazine, February 1999.

12. Xylomenos, G., et al., “Internet Protocol Performance over Wireless Networks with Wireless Links,” IEEE Network Magazine, July/August 1999.

13. WAP Forum Specifications: http://www. wapforrum.org

14. WirelessKnowledge: http://www.wireless knowledge.com

15. Bluetooth 1.0 Specification: http://www. bluetooth.com

16. Mobile IP Overview: http://www.cis.ohio-state.edu/~jain/cis788-95/mobile_ip/index. html

17. “Use of IPSec in Mobile IP,” IETF Internet Drafts (01/08/1998): ftp://www.ietf.org/ internet-drafts/draft-ietf-mobileip-ipsec-use-00.txt

18. IETF RFCs on IPSec including RFC 768, RFC 791, RFC 793, RFC 1321, RFC 1825, RFC 1826, RFC 1827, RFC 1828, RFC 1829, and RFC 2003.

A B O U T T H E A U T H O R

Mohammed O. Zaatari is a Lead Engineer in Mitretek’s Center for Telecommunications and Advanced Technology. He has over 7 years of experience in wireless communica-tions. His experience includes system engineering and deployment of wireless networks including first and second generation Cellular Networks, Personal Communications Services Networks, LMDS Networks, and Polar Weather Satellite Systems. He also has interests in the applications of networking technologies (ATM, TCP/IP, LAN/WAN) to wireless networks. Mr. Zaatari holds BSEE and MSEE degrees from the University of Southern California; and an MS in Telecommunications Management from Southern Methodist University. E-mail: [email protected]


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Documents

Wireless Networks and Technologies in the Third Generation Era