bypass services; metropolitan area networks (MANs), wide area networks (WANs), and premises-based local area networks (LANs) are becoming ubiquitous features of business telecommunications. Teleports use satellites to establish long distance links connecting to public and private local landline networks via optical fiber links. Business data traffic can bypass local gateways to interexchange networks. Fiber MANs and WANs link business firms within the same urban area and can also bypass public network facilities. Already, according to documents filed with the Federal Communications Commission (FCC), bypass is siphoning billions of dollars in revenues from the local exchange carriers (although carriers are eligible to compete for bypass business).

National Security Emergency Preparedness Implications

Bypass stimulates duplication of network facilities, and can lead to deployment of substantial excess network transmission capacity. Intense competition for limited customer demand can drive providers to offer prestandard or nonstandard offerings in an effort to get the jump on competitors. Manual or automatic network reconstitution mechanisms can ameliorate somewhat the NSEP problems posed by networks not configured to prevailing general standards. When telecommunications is opened to competition by many carriers, some initial incompatibilities will arise. Work in the Exchange Carriers Standards Association Telecommunications Committee (T-1) indicates that user demands for open system access in the marketplace are motivating vendors to standardize interfaces.

CELLULAR MOBILE RADIO

Background

Since its commercial introduction in 1983, cellular mobile radio has greatly increased mobile channel capacity in major urban markets and brought high-capacity mobile service to many smaller areas. Cellular is a mature technology initially tested in 1970: Vehicles with cellular phones communicate with a centrally located fixed transceiver site, which is linked via terrestrial lines to a computerized mobile telephone switching office (MTSO) which, in turn, interconnects the landline telephone networks to the cellular system. Cellular systems are subdivided into “cells”; as a user passes from one cell to the next the call is “handed off” to the next cell. This



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