Telephone interexchange carrier selection

Abstract

Disclosed are methods and apparatuses for selecting an interexchange telephone call carrier, selecting a route to the selected carrier, and establishing a call path on the selected route to the selected carrier in a multi-carrier environment. To select a carrier, dialed digits incoming from a terminal link to a switching office are examined to determine if the call is of an interexchange type, requiring selection of a carrier. If so, the dialed digits are examined to determine if a carrier-identifying code has been dialed. If not, a data base is checked to determine if a carrier has been predesignated for this terminal link or for a group of Centrex terminal links of which this terminal link is a member. If not, and if an option of selecting a default carrier has been implemented, the data base is checked to determine if a default carrier may be used for calls originating with the calling terminal link or with the group of Centrex terminal links. If a default carrier may be used, data base is checked to determine if a default carrier has been designated. Once an appropriate carrier for the call is found, steps are taken to connect the call to that carrier. If no appropriate carrier for the call can be identified, the call is blocked and the caller is requested to dial a carrier-identifying code.