kerberos(8)

NAME

kerberos - introduction to the Kerberos system

Kerberos is a network authentication system. Its purpose is
to securely authenticate users and services in an insecure network envi
ronment.
This is done with a Kerberos server acting as a trusted
third party, keeping a database with secret keys for all users and ser
vices (collec tively called principals).
Each principal belongs to exactly one realm, which is the
administrative domain in Kerberos. A realm usually corresponds to an organ
isation, and the realm should normally be derived from that organisa
tion's domain name. A realm is served by one or more Kerberos servers.
The authentication process involves exchange of `tickets'
and `authenticators' which together prove the principal's iden
tity.
When you login to the Kerberos system, either through the
normal system login or with the kinit(1) program, you acquire a ticket
granting ticket which allows you to get new tickets for other services, such
as telnet or
ftp, without giving your password.
For more information on how Kerberos works, and other gener
al Kerberos questions see the Kerberos FAQ at http://www.nrl.navy.mil/CCS/people/kenh/kerberos-faq.html.
For setup instructions see the Heimdal Texinfo manual.

The Kerberos authentication system was developed in the late
1980's as part of the Athena Project at the Massachusetts Institute of
Technology. Versions one through three never reached outside MIT, but
version 4 was (and still is) quite popular, especially in the academic
community, but is also used in commercial products like the AFS filesystem.
The problems with version 4 are that it has many limita
tions, the code was not too well written (since it had been developed over a
long time), and it has a number of known security problems. To resolve
many of these issues work on version five started, and resulted in IETF
RFC1510 in 1993. Since then much work has been put into the further de
velopment, and a new RFC will hopefully appear soon.
This manual manual page is part of the Heimdal Kerberos 5
distribution, which has been in development at the Royal Institute of
Technology in Stockholm, Sweden, since about 1997.
HEIMDAL September 1, 2000