Definition of Interexchange Carrier in the Network Encyclopedia.

What is Interexchange Carrier?

Interexchange Carrier, also known as IXC, is a telco that mainly provides long-distance communication services. Interexchange carriers (IXCs) own or share the various high-bandwidth, fiber-optic trunk lines that cross the country and provide high-speed switched digital services for voice, data, and video communication. About 90 percent of the U.S. long-distance communication market is controlled by the IXCs AT&T, MCI WorldCom, and Sprint.

Local telephone service to subscribers is primarily the domain of local exchange carriers (LECs) such as the Regional Bell Operating Companies (RBOCs). However, the Telecommunications Act of 1996 has opened up the market so that LECs can compete in long-distance markets by leasing services from IXCs, and IXCs can compete in local markets by leasing local loop connections from LECs. Some companies have also gained access to each other’s services by merging. Other emerging competitors for IXCs are cable television companies, who have customer premises installations in most U.S. residences and who are upgrading their networks for bidirectional communication.

Carrier identification code

Each carrier (interexchange or local exchange) is assigned a four-digit identification code, the Carrier Identification Code (CIC) which was used with feature groups. The interexchange carrier to which calls from a subscriber line are routed by default is known as the Presubscribed Interexchange Carrier (PIC). To give telephone users the possibility of opting for a different carrier on a call-by-call basis, Carrier Access Codes (CAC) were devised. These consist of the digits 101 followed by the four-digit CIC. The CAC is dialed as a prefix immediately before dialing a long-distance phone number. (see Carrier identification code FAQ)