0163-6804/99/$10.00 © 1999 IEEE he rapid growth of wireless voice subscribers, the growth of the Internet, and the increasing use of portable computing devices suggest that wireless Internet access will grow to be a major area of telecommunications services. Rapid progress in digital and RF technology is making possible highly compact and integrated terminal devices, and the introduction of sophisticated wireless data software is providing more value and making wireless Internet access more user-friendly. Data transmission rates are growing rapidly in fixed networks with the use of wavelength-division multiplexing (WDM) in backbone fiber networks, and the introduction of cable modems and high-speed digital subscriber line technology in fixed access networks. Increasingly demanding Internet applications and user expectations are emerging. Experience with laptop computers and personal digital assistants has shown that many end users desire their portable equipment to provide much of the same environment and applications they enjoy at their desks. Experience with wireless access has also demonstrated the singular importance of widespread coverage and anywhere/anytime access.