The TCP/IP Guide  9  Networking Fundamentals       9  Network Standards and Standards Organizations

Internet Standards Organizations (ISOC, IAB, IESG, IETF, IRSG, IRTF) 1 2 3 Internet Standards and the Request For Comment (RFC) Process

Modern Hierarchy of Registration Authorities

In the original “classful” IP addressing scheme, addresses were assigned to organizations directly by IANA in address blocks: Class A, Class B and Class C addresses. Today, a hierarchical, classless addressing system called Classless Inter-Domain Routing (CIDR) is used instead. Address assignment in CIDR involves the hierarchical allocation of blocks of addresses, starting with large blocks that are given to big organizations, which split them to assign to smaller groups. (Much more detail on these methods can be found in the large section on IP addressing.)

IANA, as the organization in charge of all IP addresses, assigns the largest blocks of addresses to regional Internet registries (RIRs) that are responsible for further allocation activities. Each RIR manages IP addresses and other Internet number resources (such as autonomous system numbers) for a particular region. The four regional registries are:

• Asia Pacific Network Information Centre (APNIC): Covers the Asia/Pacific region.
  
  
• American Registry for Internet Numbers (ARIN): Manages North America, part of the Caribbean, and sub-equatorial Africa.
  
  
• Latin American and Caribbean Internet Addresses Registry (LACNIC): Responsible for Latin America and part of the Caribbean.
  
  
• Réseaux IP Européens Network Coordination Center (RIPE NCC): Takes care of Europe, the Middle East, Central Asia, and Africa north of the equator.

Each registry may assign address blocks to Internet service providers (ISPs) directly, or further delegate them to national Internet registries (NIRs) or smaller local Internet registries (LIRs). See the topic on IP address allocation issues for more details.

Name registration has changed over the last several years. It is no longer part of IANA’s responsibilities, and ICANN has opened up the name registration business so it is no longer the province of a single organization such as InterNIC/Network Solutions/Verisign. Now, many different accredited registrars can be used for name registration in many of the popular top-level domains. This is discussed in the topic on DNS public registration.

Internet Standards Organizations (ISOC, IAB, IESG, IETF, IRSG, IRTF) 1 2 3 Internet Standards and the Request For Comment (RFC) Process