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Future Of Wireless Networking Essay Research Paper

For each of the past five years, industry pundits have been convinced it would be the year of wireless data in the wide-area environment. And every year it was for a different reason: support for IP protocols; phones with microbrowsers; support from industry giants, such as Microsoft and IBM; and new platforms, such as handheld computers. This year s reasons include WAP (Wireless Application Protocol_ and the forthcoming GPRS (General Packet Radio Service (Internet Wide-Area Wireless Computing ). Meanwhile, the latest buzz is about third-generation cellular and data throughputs of 2 Mbps is just around the corner.

Network managers are faced with a difficult situation. The people they support are increasingly demanding wireless access to the corporate network. These people have experienced the advantages of wireless networks for voice communications. Now they want those advantages for data communications, especially as massive promotional efforts by major operators have significantly increased awareness of these services. Meanwhile, millions of palm-sized devices are begging to have wireless connections for applications such as e-mail and schedule synchronization (Internet, A World Without Wires ). And who wouldn t want to be able to access a Microsoft Exchange or Louts Notes server when stuck at an airport gate? Wireless networking promises both greater work productivity and increased flexibility in our lifestyles.

By next year, cellular operators will be offering IP packet-data services with rates as high as 144 Kbps, though 56 Kbps will be more typical of downlink speeds. This is in sharp contrast with today s services, which are limited to about 9.6 Kbps (Internet A World Without Wires ). However, the industry is fragmented, with multiple wireless technologies grouped, each with its own data strategy. Understanding how these data services will evolve will let you take better advantage of these developments. To obtain some fundamental insight into this industry, you should realize there are huge market forces at play that will determine how and when next-generation data services will be arranged. Unfortunately, these forces are not all in alignment. Understanding this interplay will help you make your own predictions. One force driving the broad deployment of new data services is the huge success of wireless voice, leading the industry to view data as a vast new source of potential revenue. Data is also now an integral part of next-generation cellular systems, not just an afterthought. Complementary industry developments, including new handheld platforms and new delivery methods, such as WAP, also help. Finally, the massive alliance in the wireless industry will make it easier for operators to arrange services over a nationwide if not a global scale (Internet Wide-Area Wireless Computing ).

There are some key attributes about wireless networking services though. First, they are slow. They weren t when they were designed, at the beginning of the 1990 s, but today s typical rates of 9.6 Kbps to 14.4 Kbps simply do not stand up to demands of rich Web pages and heavy-duty productivity applications like Microsoft Exchange an Lotus Notes. Second is the emphasis on circuit-switched connections. With data as an afterthought for current digital cellular systems, a dial-up model for data is easier to deploy than a packet-switched architecture. But dial-up means connection delays, an inability to push data to mobile users and having to pay for connect times even sessions are idle (Internet Wireless World Spawns New Data Device Breed ).

Nevertheless, today s wireless networks can be used productively as long as only small amounts of data are involved. In many instances, customers need to employ wireless middleware solutions that account for the limitations of today s wireless networks. Internet portals are also now targeting this industry by developing mobile content that can be accessed by new microbrowser-equipped cell phones, giving users access to their e-mail, calendar, travel, entertainment and restaurant information; sports results; package tracking; horoscopes and so on. Despite some of these new consumer-oriented services, wireless networks today are used mostly for messaging applications or in vertical markets (field service, for example) (Internet A World Without Wires ).

Not only is there a tremendous amount of new wireless technology in development, but a good chunk of it is about to be deployed. The best way to get a clear picture is to examine the data strategies for the three principal digital cellular technologies. In the U.S., the two dominant cellular technologies are TIA/EIA-136, which is TDMA (time-division multiple access) technology, and IS-95, a CDMA (code-division multiple access) technology. TDMA, the oldest U.S digital technology, divides radio channels into three time slots, with each user receiving a distinct slot. This method enables three users on each radio channel to communicate without interference. CDMA, a newer U.S. digital technology, uses spread-spectrum technology, in which many users share the same radio channel simultaneously but are distinguished by unique pseudo-random codes. Both are considered second-generation cellular technologies, with analog cellular being first generation (Internet Wireless World Spawns New Data Device Breed ).

The largest TDMA carriers are AT&T Wireless Services and SBC Communications, while the largest CDMA carriers are Sprint PCS and Verizon. GSM (Global System for Mobile Communications) technology is a distant third in the U.S but dominates worldwide. In the U.S., the dominant GSM carrier is VoiceStream. AT&T Wireless Services, Sprint PCS and VoiceStream all offer nationwide coverage (Internet Wireless World Spawns New Data Device Breed ).

Cellular technology gets the lion s share of attention, but network managers should keep their eyes open to other wireless providers. One is Metricom, which is rolling out a wireless data service called Ricochet2, with rates of 128 Kbps. With strong backing from MCI WorldCom, Metricom expects to have services deployed in more than 35 metropolitan areas by this year, reaching 100 million potential subscribers (Internet Wide-Area Wireless Computing ). If cellular carriers execute their data plans aggressively, Metricom might offer too little too late, but if cellular carriers stumble, Metricom could scoop up cellular-crazed mobile customers.

Wireless LANs promise productivity enhancements and flexibility, operators are broadly promoting new services, while new platforms, such as handheld computers and phones with microbrowsers, enable new applications. However, widespread use of wireless networking also proved elusive because of slow speeds, high costs and complex deployments that often require middleware (Internet Wireless LANs Work Their Magic ). But high-speed data technology could increase the utility of the wireless services. Although it is targeted initially for private deployments, there is an increasing interest in public arrangement, such as airports, shopping malls and hotels. Some cellular operators may eventually offer a blend of access options, with cellular in wide areas and WLAN technologies in high-density environments (Internet Wireless LANs Work Their Magic ).

The wireless industry is driven by the desire for new revenue sources and has designed data services as a core function of next-generation networks. For customers, which technology prevails may not be a huge factor. Most of the technology I discussed in my will offer high-speed wireless IP networking, and customers will easily be able to port applications from one network to the other. And multimode devices in the future may even make it possible to roam between these networks (Internet Wide-Area Wireless Computing ). In the meantime, this will be a grand phenomenon to observe.

List of Works Cited

Bibliography

1. A World Without Wires (Network Computing, July 10, 2000) www.nwc.com/1113/1113f1.html

2. Wireless LANS Work Their Magic (Network Computing, July 10, 2000) www.nwc.com/1113/1113f2.html

3. Wireless World Spawns New Data Device Breed (Planet IT, March 7, 2000) www.planeit.com/techcentersdocs/mobileomputing/news/PIT20000307S0006

4. Wide-Area Wireless Computing (Network Computing, Network Design Manual) www.nwc.com.netdesign/wireless1.html




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