LEAST COST ROUTING METHOD ACCORDING TO INFORMATION TRANSFER CAPABILITY OF CUSTOMER PREMISES EQUIPMENT

摘要

ISDN subscriber line interface circuits of a switching system servecustomer premises equipment of different information transfer capabilities.Least cost routing data and corresponding digit conversion data are storedin a memory, with the routing data indicating least cost outgoing routesthrough an ISDN network. These data are retrieved from the memoryaccording to the called party number and information transfer capabilityfield of a call setup message received from a calling party. The calledparty number is then converted according to the retrieved digit conversiondata, and an ISDN trunk circuit is selected according to the retrieved leastcost routing data. A connection is established between the originatingISDN SLIC and the selected ISDN trunk circuit, and the converted calledparty number is transmitted through a signaling channel to the ISDNnetwork.