Contains public or secret keys for maps.
The /etc/publickey file is the public key file used for secure networking. Each entry in the file consists of a network user name (which may refer to either a user or a host name), followed by the user's public key (in hex notation), a colon, and then the user's secret key encrypted with its login password (also in hex notation). This file is part of the Network Support Facilities.
This file is altered either by the user through the chkey command or by the person who administers the system through the newkey command. The publickey file should only contain data on the master server, where it is converted into the publickey.byname NIS map.