Network Information Service

The Network Information Service or NIS (originally called Yellow Pages or YP) is Sun Microsystems’ client-server directory service protocol for distributing system configuration data such as user and host names between computers on a computer network.Sun licenses this technology to virtually all other Unix vendors.As the name “Yellow Pages” was a registered trademark in the United Kingdom of British Telecom PLC for their (paper) commercial telephone directory, Sun changed the name of their system to NIS, though all the commands and functions still start with “yp”.
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<networking, protocol> (NIS) Sun Microsystems' Yellow Pages (yp) client-server protocol for distributing system configuration data such as user and host names between computers on a network.
Sun licenses the technology to virtually all other Unix vendors.
The name "Yellow Pages" is a registered trademark in the United Kingdom of British Telecommunications plc for their (paper) commercial telephone directory. Sun changed the name of their system to NIS, though all the commands and functions still start with "yp", e.g. ypcat, ypmatch, ypwhich.
Unix manual pages: yp(3), ypclnt(3), ypcat(1), ypmatch(1).
(1995-04-08)