at they only use a relatively small percentage of what they hold appears to be irrelevant. It's high time federal regulators redistribute spectrum as appropriate to level the services playing field. "Water, water everywhere and not a drop to drink," is the mantra of would-be wireless providers. TV has historically con- trolled 15 percent of the most desirable spectrum (30-30,000 MHz) yet wireless television (i.e., antenna-based) serves only 11 million U.S. households. The rest are served by cable and satellite providers who don't use the most desirable spectrum to begin with. Cellular providers have half the spectrum allocated to them that TV has; yet, they must serve hundreds of millions of subscribers in that space. The ITFS spec- trum that was set aside in the 1960s (see section on MMDS, which fol- lows) for education purposes still sits largely unused; yet, Wi-Fi providers must pack 20 million users into half the spectrum available to ITFS users. The good news is that recent regulatory activity indicates that the FCC may be considering a "gerrymandering of the available spectrum," so stay tuned-no pun intended. Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. Access Technologies Access Technologies Fixed Wireless Technologies A number of fixed broadband wireless technologies have emerged that present a potential alternative to traditional wired access infrastruc- tures. These include Local Multipoint Distribution Service (LMDS), Mul- tichannel Multipoint Distribution Service (MMDS), 802.11 (Wi-Fi), and Freespace Optics. Local Multipoint Distribution Service (LMDS) LMDS is a bottleneck resolution technology, designed to alleviate the transmission restriction that occurs between high-speed LANs and wide area networks (WANs). Today, local networks routinely operate at speeds of 100 Mbps (Fast Ethernet), 1,000 Mbps (Gigabit Ethernet), and eve