An Internet number is a numerical identifier assigned to an Internet resource or used in the networking protocols of the Internet Protocol Suite. Examples include IP addresses and autonomous system (AS) numbers. Globally, Internet numbers are managed by the Internet Assigned Numbers Authority, an organization operated by the Internet Corporation for Assigned Names and Numbers (ICANN). In addition, five regional Internet registries delegate number resources to their customers, local Internet registries, such as Internet service providers, and end-user organizations.
An organization able to assign parts of its allocation from a regional Internet registry is called a local Internet registry. Most local Internet registries are Internet service providers.