Whois
What is WHOIS?
WHOIS is a protocol that is used to query databases to obtain the registration information of a domain name or the allocation and assignment information of an IP address (IPv4 or IPv6). It provides a way to fetch ownership and administrative contact details for internet resources. The WHOIS service is used for various purposes, including determining the availability of domain names, identifying trademark infringement, and maintaining domain name registrants' accountability.
WHOIS for Domain Names
When used for domain names, WHOIS queries can return a wide range of information about a domain, such as:
The name of the domain registrant (the owner of the domain). Contact information for the registrant, including address, phone number, and email address. The registration dates (creation and expiration dates) of the domain. The domain's status (e.g., active, locked, expired). The nameservers assigned to the domain. The registrar managing the domain (the service used to register the domain). This information is useful for contacting the domain owner for various reasons, such as negotiations for purchasing the domain, reporting issues, or legal purposes.
WHOIS for IP Addresses
When used for IP addresses, WHOIS queries are directed at databases maintained by Regional Internet Registries (RIRs) responsible for allocating IP address blocks to organizations and service providers. There are five RIRs, each responsible for a specific region of the world:
ARIN (North America) RIPE NCC (Europe, Middle East, and Central Asia) APNIC (Asia-Pacific) LACNIC (Latin America and the Caribbean) AFRINIC (Africa)
WHOIS queries for an IP address can return information such as:
The organization to which the IP address has been allocated or assigned. Contact information for administrative and technical handling of the IP address. The allocation or assignment date. The status of the IP address (e.g., allocated, assigned, available). This information can be crucial for troubleshooting network issues, conducting security investigations, or understanding the distribution and assignment of IP addresses globally.
Privacy Concerns and Changes
Due to privacy concerns, WHOIS services have evolved over time. Nowadays, personal information may be redacted or protected by privacy services provided by domain registrars. This change has been partly due to regulations such as the General Data Protection Regulation (GDPR) in Europe, which restricts the public display of personal information. Nonetheless, WHOIS remains a vital tool for administrative and technical queries related to internet resources.