The North American Numbering Plan (NANP), International Calling, The Presubscribed Interexchange Carrier (PIC), Charge CIC (Carrier Identification Codes) and Dial-Around, Toll-Free Services, and How to Buy Long Distance Services

Long distance systems are a network of switching systems and circuits that haul telephone traffic between local exchange areas (Local carriers are called LEC for Local Exchange Carriers or, if they used to be Bell-related, ILEC for Incumbent Local Exchange Carrier.). Long distance carriers are usually called IXC or Interexchange Carriers.

Your long distance calls leave your business over LEC facilities, are transferred to your IXC s network, can be transferred to and from a competing carrier, and are finally sent back to the LEC at the destination end.

The North American Numbering Plan (NANP)

The NANP (North American Numbering Plan) was designed as a closed ten digit national numbering plan. The routing codes for the NANP have three parts: a three digit area code or Numbering Plan Area (NPA) code, a three digit Central Office (CO) code (or NNX), and a four digit station number.

Together, these ten digits comprise the network address or destination code for each telephone number.

International Calling

International dialing uses an open numbering plan capable of handling from 7 to 15 digits.

IDDD (International Direct Distance Dialing) was first introduced in 1970. The prefixes 011 for station to station calls and 01 for operator assisted calls are used for IDDD calling according to the NANP (North American Numbering Plan).

The worldwide numbering plan divides the world...