The CIA triad and encryption

Security experts often describe the goals of information security with the CIA triad. Confidentiality means only authorized people can see the information; integrity means the information is accurate and has not been changed without permission; and availability means the information and systems are there when authorized people need them. A breach of any one causes harm: leaked medical records break confidentiality, a tampered grade breaks integrity, and a website knocked offline breaks availability. Encryption protects confidentiality by scrambling readable data (plaintext) into unreadable data (ciphertext) using a key. A simple Caesar cipher shifts each letter, so with a shift of 3, "CAT" becomes "FDW." In symmetric encryption, the same key encrypts and decrypts. In public-key encryption, anyone can use a person's public key to encrypt a message, but only that person's private key can decrypt it. Secure websites using HTTPS combine the two: public-key cryptography verifies the website and sets up a shared session key, and faster symmetric encryption then protects the data sent during the connection.

This explanation is AI-generated and can occasionally be wrong. 🚩 Report