Table of Contents 
ImplementationsTable of Contents Implementations
Whois is a draft standard protocol. Its status is elective. The current Whois specification can be found in RFC 954 - NICNAME/WHOIS.
The Whois program is commonly used in the UNIX environment to connect to a Whois server. The purpose of the server is to provide directory type services. The original Whois server was set up so that the Network Information Center could maintain a contact list for networks connected to the Internet. However, many sites now use Whois to provide local directory services.
The Whois server is based upon TCP and uses well-known port 43. Requests and replies exchanged between the client and server use NVT ASCII.
The most widely used Whois server is maintained by the InterNIC and can be reached at rs.internic.net.
AIX systems implement both the Whois client and server. Warp Internet Connection provides the Whois client.
Time
and Daytime Protocols