In addition to providing secure authentication of users, the Kerberos service provides two security services:
Integrity – Just as authentication ensures that clients on a network are who they claim to be, integrity ensures that the data they send is valid and has not been tampered with during transit. Integrity is done through cryptographic checksumming of the data. Integrity also includes user authentication.
Privacy – Privacy takes security a step further. Privacy not only includes verifying the integrity of transmitted data, but it encrypts the data before transmission, protecting it from eavesdroppers. Privacy authenticates users, as well.
Developers can design their RPC-based applications to choose a security service by using the RPCSEC_GSS programming interface.