Data security requirements can be broken down into three basic categories:
• Confidentiality ensures that data cannot be intercepted and read while it is in transit. It prevents sniffing and other forms of unauthorized access to data, either in transit or at rest.
• Integrity ensures that the data itself is valid—that it has not been altered in transit. It also prevents replay attacks in which an intruder captures and replays messages to gain access or tamper with data.
• Authentication ensures that the originator of a message is an authorized user and that the user is who they say they are. Authentication prevents access by unauthorized users.