The North American Numbering Plan (NANP) is a Telefonnumerierungsplan that covers 25 different regions in twenty countries, especially in North America, including the Caribbean and the US territories. Not all North American countries participate in the NANP.
More SourceA Telephone numbering plan is a type of numbering scheme used in telecommunications to assign phone numbers to subscriber phones or other telephone endpoints. Telephone numbers are the addresses of subscribers in a telephone network that are reachable by a system of route routing. In each administrative area of the public telephone Network (PSTN), telephone number plans are established, which are also available in private telephony networks. For public numbering systems, the geographic location plays a role in the order of the numbers assigned to each telephone subscriber.
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