Wireless Local Area Networks (WLAN) fall into two primary categories: public and private. In 2003, public wireless LAN locations, known as "hotspots," numbered approximately 30,000, but research suggests the number will more than quadruple by 2006. Private wireless LANs are also becoming increasingly common in corporate environments to meet the changing definition of a mobile employee: from someone out in the field to someone who moves around the corporate complex and needs to retain network access as he or she roams from place to place. The technology is being driven by four major standards.

• Bluetooth. Bluetooth wireless technology provides links between mobile computers, mobile phones, and portable handheld devices, as well as connectivity to the Internet. Bluetooth operates at 2.4 GHz, and has a range of about 10 meters.
• IEEE 802.11b "WiFi." WiFi runs in the 2.4 GHz range, and has a maximum speed of 11 megabits per second. 802.11b has a range of about 100 meters indoors and 300 meters outside. It is prone to interference from 2.4 GHz cordless phones and microwave ovens.
• IEEE 802.11a. 802.11a runs in the 5 GHz range, and has a
  maximum speed of about 54 megabits per second. 802.11a is not prone to interference like WiFi because it is in a largely unused frequency range. However, 802.11a has a shorter range and requires more access points to cover the same area. It is also not backwards compatible with WiFi.
• IEEE 802.11g. 802.11g supports a higher transmission speed of 54 megabits per second, is completely backwards compatible with WiFi, and benefits from the longer range of WiFi. However, 802.11g operates in the 2.4 GHz band, so it does have the same interference problems as WiFi.

Wireless Internet and Wide Area Networks (WWAN)

WiFi and the other IEEE 802.11 standards were developed as local area networking technologies. They were never designed to cover wide areas and support true mobility by allowing roaming from one access point to another without service interruption. For the most part, developments in the field of wide area data networking remain the domain of the telecommunications industry, and these players view public WLAN implementations like WiFi hotspots as an encroachment on their territory. The industry argues that you wouldn't need hotspots if wireless data access was as comprehensive as cellular voice. Vendors are pushing WiFi in the short-term to drive market demand, but expect to eliminate the need for WiFi hotspots in the future.

The telecommunications industry is focused on developing third generation wireless systems (known as 3G) to deliver high-speed, wide-are coverage. Three important technologies will play an important role in the development of 3G:

• Universal Mobile Telecommunication System (UMTS). UMTS is an extension of the existing Global System for Mobile Communications (GSM) network that uses the Wideband Code Division Multiple Access (WCDMA) air interface to deliver broadband quality transfer speeds over wide areas.
• Code Division Multiple Access (CDMA) 2000. The second generation of the CDMA standard (IS-95) is CDMA 2000. The first version provides transfer speeds of up to 614 kilobits per second, but a new data-optimized version promises much higher transfer speeds.
• Time Division Synchronous Code Division Multiple Access (TD-SCDMA). TD-SCDMA systems can be connected to existing GSM networks, which allows simple and cost-effective internetworking between 2G and 3G network operations. Data can be sent and received while traveling at very high speeds of up to 150 mph.

For more information on choosing the right wireless solution for your company, please read our Wireless First Steps.

Go to Bitpipe Research Guide: Wireless.