- ICANN (Internet Corporation for Assigned Names and Numbers) [established: 1999]
- Responsible for managing the Internet Protocol address spaces (IPv4 and IPv6) and assignment of address blocks to Regional Internet Registries (RIRs), for maintaining registries of Internet protocol identifiers, and for the management of the top-level domain name space (DNS root zone), which includes the operation of root nameservers.
IANA (Internet Address and Naming Agency)
Oversees global IP address allocation, autonomous system number allocation, root zone management in the Domain Name System (DNS), media types, and other Internet Protocol-related symbols and numbers. IANA is operated by ICANN.
RIRs (Regional Internet Registry) are responsible global regional management of Internet numbering resources, including the IPv4 and IPv6 address space allocation for different areas of the world.
- APNIC (Asia Pacific Network Information Center) [established: 1993]
- ARIN (American Registry for Internet Numbers) [established: 1997]
- LACNIC (Latin American and Caribbean Internet Addresses Registry) [established: 2002]
- RIPE NCC (RIR for Europe and Middle East) [established: 1992]
- AfriNIC [established: 2005]
- The existing IPv4 protocol has a 32-bit address space providing for a theoretical 2^32 (approximately 4 billion) unique globally addressable network interfaces.
- IPv6 has a 128-bit address space that can uniquely address 2^128 (about 340 sexillion) network interfaces.
A very brief history IP Address Space:
- 2/3/11 - RIPE NCC received the final block of available IPv4 addresses (185/8). "A pool of more than 4 billion Internet addresses has just been emptied this morning—completely depleted,” said Rod Beckstrom, president and CEO of ICANN (the Internet Corporation for Assigned Names and Numbers) on a panel at a press conference following the ceremony. “There are no more,” he said.
- 1977 - Vint Cerf, “father of the Internet,” selected the 32-bit system because he thought a pool of 4.3 billion possible IP addresses would be “enough to do an experiment.