WHOIS is a famous protocol chiefly used for database query to determine the information of Internet resources like domain name, IP address, or any autonomous address. WHOIS lookup is basically performed with command user interface. Many web-based tools are available to perform WHOIS query. This service is usually communicated using the Transmission Control Protocol (TCP). Server listens to the request on the port number 43. The WHOIS system is originally developed for the system administrator to acquire contact information for different IP address or domain name administrators. Now a days WHOIS lookup query evolved into various different important aspects, including:

• It helps in determining the registration status of domain names.
• WHOIS also helps in law enforcement by various authorities in investigations for enforcing national and international laws.Specialized non-governmental bodies may be involved in this work of law enforement using this database query service.
• WHOIS lookup also help businesses, organizations and users in fighting fraud, complying with relevant laws and safeguarding the interests of the public properties.

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