ICANN Acronyms and Terms

The entire range of possible Internet Protocol version 4 (IPv4) and Internet Protocol version 6 (IPv6) addresses managed by Internet Assigned Numbers Authority functions.

The first version of the Internet Protocol (IP) to gain popular use. The Defense Advanced Research Projects Agency developed IPv4 in the early 1980s. With an address length of 32 bits, IPv4 has a capacity of just over four billion unique IP addresses. After years of rapid Internet expansion, its pool of available addresses has been fully allocated to Internet services providers and users.

IPv4 addresses are written as a sequence of four decimal values between 0 and 255, separated by dots. A typical IPv4 address looks like this: 192.0.2.67.

The latest version of the Internet Protocol (IP). The Internet Engineering Task Force developed IPv6, and the protocol became an IP standard in 1996. With an address length of 128 bits, IPv6 has a capacity for 340 undecillion unique IP addresses.

IPv6 addresses are written using sequences of hexadecimal values, separated by colons. A typical IPv6 address looks like this: fd84:69e1:1ce7::25.

A body of experts who perform research that is critical to the evolution of the Internet. The IRTF is composed of several focused and long-term research groups. Topics that these groups explore include decentralized infrastructure services, cryptographic mechanisms, congestion control, and thing-to-thing communication. Often, the findings of IRTF research are applied and standardized by its sister group, the Internet Engineering Task Force (IETF).

A company that primarily provides Internet access for organizations and individuals. Besides Internet access, ISPs often provide services such as web hosting, email, and voice over Internet Protocol (VoIP).

A constituency within the Commercial Stakeholder Group of the Generic Names Supporting Organization. The ISPCP represents the interests of Internet service providers and other entities that operate backbone networks or provide transit to Internet users and third-party content. The ISPCP also represents the interests of entities that provide electronic commerce services, application services, or managed security services over the Internet.

The international organization for global cooperation and coordination for the Internet and its internetworking technologies and applications. The Internet Society supports and promotes the development of the Internet as a global technical infrastructure, a resource to enrich people’s lives, and a force for good in society. ISOC membership is open to any interested person. Regional ISOC chapters across the globe focus on promoting ISOC’s mission locally.

As defined in RFC 2026, a “specification that is stable and well-understood, is technically competent, has multiple, independent, and interoperable implementations with substantial operational experience, enjoys significant public support, and is recognizably useful in some or all parts of the Internet.”

The agency within the International Organization for Standardization that is tasked with updating, implementing, and maintaining the ISO 3166 standard that defines codes of letters used to refer to countries and subdivisions. The Internet Assigned Numbers Authority uses the two-letter names defined in ISO 3166-1 as identifiers for country code top-level domains. ISO 3166/MA is responsible for any updates, for example, when a country code is created or ceases to exist.