Provides telecommunication managers of large, especially multisite, companies, a basis of information and comparisons helpful in negotiating with the long-distance carriers (Sprint, MCI, AT&T) for private network service that can be customized to fit particular needs. Explains how each of the three networks is designed and functions, and evaluates its reliability. Special attention is given to the software-defined features and applications. No bibliography. Annotation copyright Book News, Inc. Portland, Or.