What Is IANA? The Internet Assigned Numbers Authority

4 min read
12 October 2021
Edvinas Račkauskas

The Internet Assigned Numbers Authority plays a major role in today's internet. However, not many know about this organization or its responsibilities. Continue reading to learn all about IANA.

Internet Assigned Numbers Authority - IANA

IANA, or the Internet Assigned Numbers Authority, is an organization responsible for the assignment of numbering systems and unique names that form the backbone of the global internet. 

IANA effectively manages registries that deal with three categories of Internet identifiers:

  • IP addressing (Internet Protocol addresses)
  • DNS (Domain Name System) root zone management
  • Internet Protocol resources/parameters

Even though the internet is not centralized, we need to manage some of its key elements centrally to achieve global coordination. IANA functions as the administrator that handles this critical coordination. It is one of the several authorities that enable the World Wide Web to be what it is today. 

Now that you know what IANA is, we can move forward. Due to the importance of IANA’s role in the global internet, we make sure to cover its responsibilities, history and relations to other organizations like ICANN (Internet Corporation for Assigned Names and Numbers).

History of IANA

The need to manage IP addresses, Internet Protocols and the DNS was apparent from the early days of the internet. In the beginning, a single person handled the tasks that now require an entire organization such as IANA. His name was Jon Postel

In the early 1970s, while working at the University of California, Los Angeles (UCLA), Postel was instrumental in employing the ARPANET protocols and, essentially, building the predecessor of today’s internet. Postel quickly figured out that administering and managing socket numbers was important.

A socket number is a combination of an IP address and a port number. A socket number effectively addresses specific applications on specific computers. 

IP address and port number separated in the socket address example.
An example of a socket number

Even though it was easy to manage ARPANET in the early 70s, Postel realized that we shouldn’t use the same numbers for different applications. 

Postel was known as the Czar of Socket Numbers at the Information Sciences Institute (ISI) at the University of Southern California when he became responsible for handling them. However, officially, DARPA (Defense Advanced Research Projects Agency) handled this responsibility. 

The Internet Assigned Numbers Authority came into the picture in 1988. Until 1998, both DARPA and ISI funded it. 

NTIA (National Telecommunications and Information Administration) at the United States Department of Commerce released the Management of Internet Names and Addresses white paper in 1998. This is when ICANN, a private organization, became responsible for IANA. 

The US government continued supervising the authority until 2016. Afterward, IANA’s responsibilities moved entirely to the private sector.

IANA Responsibilities

IANA maintains an administrative role over the three main types of internet identifiers:

  • DNS root zones
  • IP addresses and ASNs
  • Protocol parameters

The primary function of IANA is to make sure these essential values and names remain unique and publicly available. 

A table representing IANA's responsibilities.
How IANA oversees the internet’s resources

To understand what all of this means exactly, let’s take a look at each of the three responsibilities and what IANA actually does.

DNS root zone

The DNS is a hierarchical database that connects domain names to an IP address. This further enables computers to send data to each other. 

IANA is responsible for domain name management of DNS root servers and the DNS root itself. In simpler terms, IANA manages the DNS root zone that keeps the data at the top-level domains like .com and .net. 

IANA also administers the central collection of all allowed internationalized domain names. They are commonly known as special character domains. 

IP addresses

IANA manages the global pool of IP addresses (both IPv4 and IPv6 addresses). It also manages AS numbers (ASNs) that are assigned to five Regional Internet Registries (RIRs). 

Each RIR handles a specific part of the globe:

  • AFRINIC – Africa
  • APNIC – East Asia, Australia and Oceania
  • ARIN – USA, Canada and some Caribbean islands
  • LACNIC – South America, Mexico and some Caribbean islands
  • RIPE NCC – Europe, Middle East and Central Asia

IANA assigns blocks of IP addresses to each Regional Internet Registry. Subsequently, RIRs split the blocks into smaller blocks and assign them to respective National Internet Registries (NIRs) and Local Internet Registries (LIRs). 

Finally, these registries pass the blocks of IP addresses to different internet service providers that handle your internet connection. 

IANA reserves these blocks of private IP addresses for network administrators:


Protocol parameters

For the internet to work, a mutual understanding between computers is necessary. That’s where protocol parameters, or specific numbers used in networking protocols, come into the picture.

For computers to understand each other, these protocol parameters need to be unique. Thus, IETF (Internet Engineering Task Force) introduced technical protocol standards. 

IANA’s task here is to maintain and publish the protocol registries so that software makers can enable seamless communication. 

Some of the common parameters are:

  • HTTP status codes 
  • Port numbers 
  • Language abbreviations 

HTTP status codes inform a user if a request to a server has been processed successfully, if authentication is needed or if an error occurred. For instance, the dreaded 404 (Not Found) error that all internet users know is an HTTP status code, but there are many other HTTP status codes.

404 HTTP status code warning on a computer.
An example of an HTTP status code

Port numbers help identify the senders and recipients of data packets. There are 65,535 ports per IP address, and they all fall into different categories. Each port is reserved for a particular task. For example, port 80 is used for surfing the web. 

IANA handles ports up to port 49,151, while the remaining ones are dynamic and not connected to a specific application.

Language abbreviations show the language of specific content. EN determines English, ES determines Spanish, FR determines French and so on. 


The Internet Assigned Numbers Authority is effectively a division of ICANN. This nonprofit organization comprises numerous groups that represent different databases. 

The US Department of Commerce tasked ICANN to manage IANA from 1998. However, as of 2016, ICANN incorporated the Public Technical Identifiers, an affiliate corporation from California, to take over the management of IANA.

The incorporation occurred after the contract with the Department of Commerce expired. This event is important as it effectively made IANA part of the private sector. 

Since 2018, IANA has been managed by Kim Davies. Jon Postel and Joyce K. Reynolds managed it until 1998. Up until Davies took the seat in 2018, three other people managed the organization, each for a few years.


As you can see, the Internet Assigned Numbers Authority is an important organization that coordinates numerous activities. These activities make the global internet possible. 

IANA maintains the time zone database. It keeps track of domain names, IP addresses, ASN numbers and protocol parameter identifiers. This is what enables the internet we know and love today to support global virtual communication.

About the author

Edvinas Račkauskas

Business Analyst

Edvinas is a Business Analyst at IPXO. Besides providing his insights into the IPv4 market, Edvinas specializes in internet governance, specifically Regional Internet Registries’ policies and regulations. During his free time, Edvinas enjoys exploring new places and travelling to exotic lands.
Table of contents

Related reading

A computer, a communications tower and the internet.
15 April 2022   •   Internet Governance

What Is an ISP? A Comprehensive Guide to Internet Service Providers 

Internet Service Providers play an important role in the world of internet. Learn what ISPs do, what responsibilities they assume and what types of connections they facilitate.

Read more
AFRINIC service region
3 December 2021   •   Internet Governance

AFRINIC: A Comprehensive Guide to the Regional Internet Registry of Africa

Learn more about the African Network Information Centre, where and how it operates, and how it was established.

Read more
A world map with South East Asia and Oceania regions highlighted in pink.
29 November 2021   •   Internet Governance

APNIC: All You Need To Know

The Asia Pacific Network Information Centre plays an important role in the management of the internet. Keep reading to learn more about this RIR.

Read more

Subscribe to the IPXO email and don’t miss any news!