WHOIS

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WHOIS is a query and response protocol that is widely used for querying databases that store the registered users or assignees of an Internet resource, such as a domain name, an IP address block, or an autonomous system. The protocol stores and delivers database content in a human-readable format. The WHOIS system is used by network administrators to identify and resolve problems, by law enforcement to investigate criminal activity, and by the public to find out who owns a domain name.

History

The WHOIS protocol was originally specified in RFC 812 in 1982. It was designed to look up information about users of the ARPANET, the precursor to the modern Internet. Over time, the protocol has evolved to accommodate the growing complexity and scale of the Internet.

Functionality

WHOIS operates on a client-server model. A WHOIS client sends a query to a WHOIS server, which then returns information about the queried resource. The information returned can include the name, address, and contact details of the registrant, as well as the registration and expiration dates of the domain.

WHOIS Servers

WHOIS servers are maintained by various organizations, including ICANN, RIRs, and individual domain name registrars. Each of these entities is responsible for maintaining the WHOIS data for the resources they manage.

Privacy and Data Protection

The public availability of WHOIS data has raised concerns about privacy and data protection. In response, various measures have been implemented to protect the personal information of registrants. For example, some registrars offer privacy protection services that replace the registrant's contact details with those of a proxy service.

WHOIS and GDPR

The implementation of the GDPR in the European Union has had a significant impact on WHOIS services. Under GDPR, the personal data of EU citizens must be protected, which has led to changes in how WHOIS data is collected, stored, and displayed. Many WHOIS services now limit the amount of personal information that is publicly accessible.

Related Technologies

• RDAP (Registration Data Access Protocol) is a newer protocol designed to address some of the limitations of WHOIS, including support for internationalization and more granular access control.
• DNS (Domain Name System) is a hierarchical and decentralized naming system for computers, services, or other resources connected to the Internet or a private network.

See Also

• Domain Name System
• Internet Corporation for Assigned Names and Numbers
• Regional Internet Registry
• General Data Protection Regulation
• IP address