IANA (Internet Assigned Numbers Authority)

What is IANA (Internet Assigned Numbers Authority)?

IANA (Internet Assigned Numbers Authority) is the organization that oversees the allocation of IP addresses to internet service providers (ISPs).

IANA has changed hands several times since its inception.

From 1998 to 2016, it was managed by the Internet Corporation for Assigned Names and Numbers (ICANN), a nonprofit organization under contract with the U.S. Department of Commerce.

In 2014, the Department of Commerce announced its intention to begin the IANA stewardship transition of internet domain name functions to a multistakeholder, global community.

In 2016, ICANN created Public Technical Identifiers to take over IANA functions as part of the private sector.

What are IANA responsibilities?

In addition to global IP addressing, IANA is also responsible for domain name system (DNS) root zone management, autonomous system numbers and any "unique parameters and protocol values" for the internet community.

These include port numbers, character sets, Multipurpose Internet Mail Extensions media access types and internet numbers. Internet numbers are unique identifiers assigned to resources used in networking protocols.

Internet protocols are published as Request for Comments documents that detail the research, behaviors, and enhancements of the internet and internet-related systems.

Because of this, IANA works hand in hand with the Internet Engineering Task Force and the Internet Architecture Board of the Internet Society, which work together to define standard operating internet protocols, such as TCP/IP.

Let's take a look at a few examples in depth.

Protocol assignments

IANA maintains over 2,000 protocol registries and protocol parameters. It also coordinates the registration of protocols.

Domain names

The Department of Commerce's National Telecommunications and Information Administration is responsible for maintaining a secure DNS with IANA functions as a critical component to its performance.

As part of its responsibilities, IANA facilitates root nameservers, which are at the top of the DNS hierarchy. IANA collaborates with top-level domain registrars, root nameserver operators and ICANN policymakers as part of the management of DNS.

IANA also manages DNS Security Extensions, DNS root zone servers, .INT registry for international treaty organizations, .ARPA zone for internet infrastructure, and reverse DNS service.

IP addresses

IANA delegated the responsibility for allocating IP address blocks to different areas across the globe to regional internet registries (RIRs), which then divide their address pools into smaller blocks delegated to ISPs.

To ensure their interests are represented globally, RIRs created the Number Resource Organization to oversee policy statements.

IANA designates address space in the size of /8 prefix blocks for IPv4 and /23 to /12 prefix blocks from the IPv6 block to RIRs as needed.