Explain “based on service availability”?
The U.S. telephone network is owned and operated by some 4,000+ companies and regulated by some 50+ regulatory commissions. Each company and each commission determine which services and capabilities are to be deployed, where they are deployed and when they are deployed. Because of these factors, not even long distance is equally available everywhere. For example, the capability to presubscribe to a long distance carrier of choice for local (intraLATA) toll calls is not available everywhere.
