One mechanism that supports information systems security is public key technology. Public Key Infrastructure, or PKI, provides a way to issue electronic keys, called digital certificates, to users. The digital certificate issued to the user binds the users identity to his or her public key, and in combination with the users private key, allows the user to be authenticated over open networks.
PKI also provides the infrastructure for messages or documents
to be encrypted. Thus, one infrastructure supports both confidentiality and
user authentication needs. Additionally, users automatically have the ability
to check data integrity and have a basis to ensure that the transactions cannot
later be denied or repudiated.