Authority for Addresses

Throughout an internet,each network prefix must be unique.For networks connected to the global internet,an organization obtains network numbers from the communication company that supplies internet connections.Such companies are called Internet Service Providers(ISPs).Internet Service Providers coordinate with a central organization,the Internet Assigned Number Authority,to ensure that each network prefix is unique throughout the entire Internet.For a private internet,the choice of the network prefix can be made by organization.To ensure that each prefix is unique, group that builds a private internet must decide how to coordinate network number assignments.Often,a single network administrator assign prefixes to all networks in the company's internet to ensure that numbers are not duplicated.