Other Domains

.arpa domain information

The ".arpa" stands for "Address and Routing Parameter Area," which is an infrastructure top-level domain. Initially utilized by ARPANET, it is now designated for internet technical parameters and address management. This domain is not available to the general market but is specifically used for network infrastructure technical purposes.


.arpa domain name Introduction

The ".arpa" domain stands for "Address and Routing Parameter Area," which is an infrastructure top-level domain in the internet.

Initially, "arpa" was an acronym for the Advanced Research Projects Agency, the funding organization in the United States that developed the ARPANET, the precursor to the internet. The .arpa domain was originally established for temporary purposes to systematically name ARPANET computers. However, after the domain had been approved for infrastructure use, it became difficult to remove it in practice, so the name was redefined as Address and Routing Parameter Area.

One of the most common uses of the .arpa domain is for reverse DNS lookups, which are performed when an IP address needs to be converted into a hostname. For instance, reverse lookups for IPv4 addresses are conducted within the .in-addr.arpa subdomain, while reverse lookups for IPv6 addresses take place within the .ip6.arpa subdomain.

Websites with .arpa domain names are generally not directly accessible and are used only for specific technical support within the network infrastructure.


.arpa domain name Target market

For network infrastructure, such as reverse DNS lookups (mapping IP addresses to domain names)


.arpa domain name Restrictions

Not open for registration


.arpa domain name Operator/Registry

Internet Assigned Numbers Authority


.arpa domain name Introduction date

January 1, 1985


Internet Architecture Board


.arpa domain name Intended use

The technical infrastructure used to support Internet Protocol (IP) networks was initially a temporary top-level domain to facilitate the transition from ARPANET to the DNS.


.arpa domain name Geographic restrictions

No Geographic Restrictions


.arpa domain name Renewal policy

Due to its unique nature, it generally does not involve renewal policies on the public market.


.arpa domain name Transfer policy

The standard domain transfer policies do not apply to .arpa domains; .arpa domains are not permitted to be transferred.


.arpa domain name DNSSEC Support

Yes


.arpa domain name Privacy protection

It is not supported because it is not a domain intended for registration by the general public.


.arpa domain name Pricing

None


.arpa domain name Dispute resolution policy

The .arpa domain is not of a commercial or personal nature, hence the general dispute resolution mechanisms do not apply to .arpa domain names.


.arpa domain name Registration rules

The registration of .arpa domain names is strictly limited, and general users cannot directly register and use them. Only organizations responsible for managing Internet infrastructure are eligible to use them. Currently, new subdomains are rarely added when carrying out network infrastructure engineering tasks.


.arpa domain name IDN Support

No


.arpa domain name Typical users

1. ENUM (Electronic Number Mapping) is used to map telephone numbers to Internet services - e164.arpa
2. Used for IPv6 reverse DNS resolution, mapping IPv6 addresses back to the relevant domain names - ip6.arpa
3. Used for IPv4 reverse DNS resolution, mapping IPv4 addresses back to the relevant domain names - in-addr.arpa
4. Abbreviation for Internet Registry Information Service, used to provide registry data query services - iris.arpa
5. Used for URI resolution services - uri.arpa
6. Used for resolution services of Uniform Resource Names (URN) - urn.arpa
7. Provides a special domain for residential networks, typically used for local network services - home.arpa
8. Used to support certain activities of the Internet Engineering Task Force (IETF) - ietf.arpa
9. Used to assist in implementing IPv4 connectivity in IPv6 networks - ipv4only.arpa
10. Used for hosting the authoritative DNS servers for the .arpa domain - ns.arpa


.arpa domain name Registry website

https://www.iana.org/domains/arpa