The wireless backbone
Deployment of mobile multimedia systems will depend on the rollout of high-speed wireless systems nationwide. There are two basic network types:
Wireless local-area networks — Based on the IEEE 802.11 protocols, WLANs are starting to expand in cities' "hot spots." They are capable of data rates from around 1 megabit/sec up to 50 megabits/sec, and up to distances of several miles and more.
Cellular data networks — New technologies, being tested now by telecommunications companies in Washington, D.C., and San Francisco, are capable of burst rates of up to 2.4 megabits/sec. Described as "cable modems on wheels," cellular data networks will probably be the ubiquitous wireless data networks of the future.
Brian Robinson is a freelance writer based in Portland, Ore.