NAME

       kerberos — introduction to the Kerberos system

DESCRIPTION

       Kerberos  is  a network authentication system. Its purpose is to securely authenticate users and services
       in an insecure network environment.

       This is done with a Kerberos server acting as a trusted third party, keeping a database with secret  keys
       for all users and services (collectively called principals).

       Each  principal  belongs  to  exactly  one realm, which is the administrative domain in Kerberos. A realm
       usually corresponds to an organisation, and the realm should normally be derived from that organisation'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 identity.

       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 general Kerberos questions see the Kerberos FAQ at
       http://www.cmf.nrl.navy.mil/krb/kerberos-faq.html.

       For setup instructions see the Heimdal Texinfo manual.

SEE ALSO

       ftp(1), kdestroy(1), kinit(1), klist(1), kpasswd(1), telnet(1), krb5(3), krb5.conf(5), kadmin(1), kdc(8),
       ktutil(1)

HISTORY

       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 limitations, 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 RFC 1510  in  1993.  IETF  RFC  1510  was
       obsoleted in 2005 with IETF RFC 4120, also known as Kerberos clarifications. With the arrival of IETF RFC
       4120, the work on adding extensibility and internationalization have started (Kerberos extensions), and a
       new RFC will hopefully appear soon.

       This  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                                           Jun 27, 2013                                       KERBEROS(8)