Internet Corporation for Assigned Names and Numbers (ICANN)

The Internet Corporation for Assigned Names and Numbers (ICANN) is a not-for-profit organization that manages the global system of IP addresses.

Allocation of IP addresses and domain names is delegated to a department of ICANN, IANA.

References:

http://www.icann.org/

http://www.icann.org/en/registrars/accredited-list.html