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DATA NETWORK TYPES A ROUGH SORT OF TWO-WAY SYSTEMS In North America terrestrial, two-way wireless data networks can initially be sorted into private versus public systems. Private system examples include a few very large users, such as .ederal Express, and many smaller systems for public safety (police and fire departments), taxi/limo dispatch, and utilities. In private systems the infrastructure is owned, and the spectrum is licensed, by the user. Public systems are for hire. The end user does not own the infrastructure and has no special rights to the spectrum that carries the traffic. PRIVATE SYSTEMS Overview Private. | The Wireless Data Haadbaak Fourth Edition. James F. DeRose Copyright 1999 John Wiley Sons Inc. ISBNs 0-471-31651-2 Hardback 0-471-22458-8 Electronic 2 DATA NETWORK TYPES A ROUGH SORT OF TWO-WAY SYSTEMS In North America terrestrial two-way wireless data networks can initially be sorted into private versus public systems. Private system examples include a few very large users such as Federal Express and many smaller systems for public safety police and fire departments taxi limo dispatch and utilities. In private systems the infrastructure is owned and the spectrum is licensed by the user. Public systems are for hire. The end user does not own the infrastructure and has no special rights to the spectrum that carries the traffic. PRIVATE SYSTEMS Overview Private systems are often marked by geographic constraints a metropolitan area or smaller still a railroad yard. Even Federal Express is organized on a city basis package delivery vehicles do not drive from New York to Boston though some 18 wheelers do . Often private systems have protected frequencies allocated by the Federal Communications Commission FCC for particular industry areas. Coverage requirements are frequently street level relatively few base stations aimed at vehicular targets. Thus private systems tend to be the provenance of public safety utility and taxi limo dispatch applications. No new very large private systems are being started. The constrained availability of spectrum in major metropolitan areas virtually precludes the creation of the new 11 12 DATA NETWORK TYPES 1000 user-per-city systems like those IBM initiated in 1981. Indeed IBM s private system has now been absorbed into ARDIS. In 1989 after 18 months testing GE Consumer Services selected Kustom Electronics to build its nationwide mobile data A year later Kustom began the layoffs2 that presaged its precipitous decline. In May 1991 with 60 zones operating GE announced that it would integrate its existing dispatching

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