IANA, RIR/NIR/LIR and ISPs for internet number management #

Internet Number

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 IANA.

An Internet Protocol address (IP address) is a numerical label assigned to each device (e.g., computer, printer) participating in a computer network that uses the Internet Protocol for communication.

Within the Internet, an Autonomous System (AS) is a collection of connected Internet Protocol (IP) routing prefixes under the control of one or more network operators that presents a common, clearly defined routing policy to the Internet. A group of networks and routers controlled by a single administrative authority is called an autonomous system(AS)

A unique ASN is allocated to each AS. ASN are important because the ASN uniquely identifies each network on the Internet.


The Internet Assigned Numbers Authority (IANA) is the entity that 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 a department operated by the Internet Corporation for Assigned Names and Numbers, also known as ICANN (Internet Corporation for Assigned Names and Numbers).

Prior to the establishment of ICANN for this purpose, IANA was administered primarily by Jon Postel at the Information Sciences Institute (ISI) of the University of Southern Carlifornia (USC), under a contract USC/ISI had with the United States Department of Defense, until ICANN was created to assume the responsibility under a United States Department of Commerce contract.

IANA is broadly responsible for the allocation of globally unique names and numbers that are used in Internet protocols that are published as RFC documents. Request for Comments (RFC) is a memorandum published by the Internet Engineering Task Force (IETF) describing methods, behaviors, research, or innovations applicable to the working of the Internet and Internet-connected systems. These documents describe methods, behaviors, research, or innovations applicable to the working of the Internet and Internet-connected systems. IANA also maintains a close liaison with the Internet Engineering Task Force (IETF) and RFC Editorial team in fulfilling this function.

In the case of the two major Internet namespaces, namely IP addresses and domain names, extra administrative policy and delegation to subordinate administrations is required because of the multi-layered distributed use of these resources.

IANA delegates allocations of IP address blocks to Regional Internet Registries (RIRs). Each RIR allocates addresses for a different area of the world. Collectively the RIRs have created the Number Resource Organization formed as a body to represent their collective interests and ensure that policy statements are coordinated globally.

The RIRs divide their allocated address pools into smaller blocks and delegate them in their respective operating regions to Internet service providers and other organizations. Since the introduction of the CIDR (Classless Inter-Domain Routing ) system, IANA typically allocates address space in the size of /8 prefix blocks for IPv4 and /12 prefix blocks from the 2000::/3 IPv6 Block to requesting regional registries as needed.

Following are some of the tasks associated with IANA

  • IANA administers the data in the root name servers, which form the top of the hierarchical DNS tree. This task involves liaising with top-level domain operators, the root nameserver operators, and ICANN's policy making apparatus.
  • IANA administers many parameters of IETF protocols. Examples include the names of Uniform Resource Identifier  (URI) schemes and character encodings recommended for use on the Internet.


A regional Internet registry (RIR) is an organization that manages the allocation and registration of Internet number resources within a particular region of the world. Internet number resources include IP addresses and autonomous system (AS) numbers.

Regional Internet Registries (RIRs) are established and authorized by respective regional communities, and recognized by the IANA to serve and represent large geographical regions. The primary role of RIRs is to manage and distribute public Internet address space within their respective regions.

The Regional Internet Registry system evolved over time, eventually dividing the world into five RIRs:

  • African Network Information Centre (AfriNIC) for Africa
  • American Registry for Internet Numbers (ARIN) for the United States, Canada, several parts of the Caribbean region, and Antarctica
  • Asia-Pacific Network Information Centre (APNIC) for Asia, Australia, New Zealand, and neighboring countries
  • Latin America and Caribbean Network Information Centre (LACNIC) for Latin America and parts of the Caribbean region
  • Réseaux IP Européens Network Coordination Centre (RIPE NCC) for Europe, Russia, the Middle East, and Central Asia

The IANA delegates Internet resources to the RIRs who, in turn, follow their regional policies to delegate resources to their customers, which include Internet service providers and end-user organizations.


A National Internet Registry (or NIR) is an organization under the umbrella of a Regional Internet Registry with the task of coordinating IP address allocations and other Internet resource management functions at a national level within a country or economic unit.

NIRs operate primarily in the Asia Pacific region, under the authority of APNIC, the Regional Internet Registry for that region.

The following NIRs are currently operating in the APNIC region:

  • APJII (Asosiasi Penyelenggara Jasa Internet Indonesia), Indonesian ISP Association
  • CNNIC, China Internet Network Information Center
  • JPNIC, Japan Network Information Center
  • KRNIC, National Internet Development Agency of Korea
  • SGNIC, Singapore Network Information Centre
  • TWNIC, Taiwan Network Information Center
  • VrNNIC, Vietnam Internet Network Information Center

The following NIRs are currently operating in the Latin-American (LACNIC) region:

  • NIC Argentina
  • NIC Bolivia
  • NIC Chile
  • NIC Mexico
  • NIC Brazil


A local Internet registry (LIR) is an organization that has been allocated a block of IP addresses by a regional Internet registry (RIR), and that assigns most parts of this block to its own customers. It primarily assigns address space to the users of the network services that it provides. LIRs are generally Internet Service Providers (ISPs), whose customers are primarily end users and possibly other ISPs. Membership in an RIR is required to become an LIR.

ISPs for internet number management

An Internet service provider (ISP) is an organization that provides access to the Internet. Internet service providers can be either community-owned and non-profit, or privately owned and for-profit.

In 1990, Brookline, Massachusetts-based The World became the first commercial ISP.

ISPs can be of

  • Access providers: SPs employ a range of technologies to enable consumers to connect to their network
  • Hosting ISPs: Hosting ISPs routinely provide email, FTP, and web-hosting services. Other services include virtual machines, clouds, or entire physical servers where customers can run their own custom software
  • Transit ISPs: Just as their customers pay them for Internet access, ISPs themselves pay upstream ISPs for Internet access. An upstream ISP usually has a larger network than the contracting ISP and/or is able to provide the contracting ISP with access to parts of the Internet the contracting ISP by itself has no access to.
  • Virtual ISPs: A Virtual ISP (VISP) is an operation which purchases services from another ISP (sometimes called a "wholesale ISP") which allow the VISP's customers to access the Internet using services and infrastructure owned and operated by the wholesale ISP.
  • Free ISPs: Free ISPs are Internet Service Providers (ISPs) which provide service free of charge. Many free ISPs display advertisements while the user is connected; like commercial television, in a sense they are selling the users' attention to the advertiser. Other free ISPs, often called freenets, are run on a nonprofit basis, usually with volunteer staff

History and Development of Internets and Intranets
Internet Domain and Domain Name System