End-to-end encryption (E2EE) is a secure communication process that prevents third parties from accessing data transferred from one endpoint to another. In E2EE, the data is encrypted on the senders system or device, and only the intended recipient can decrypt it. This means that the data is only viewable by those with decryption keys, and unintended users, including third parties, cannot read or modify the data when only the intended readers should have this access and ability.

E2EE is used when data security is necessary, including in the finance, healthcare, and communications industries. Many popular messaging service providers use end-to-end encryption, including Facebook, WhatsApp, and Zoom. To use end-to-end encryption in Messages, both the sender and the recipient must use the Messages app, have RCS chats turned on, and use data or Wi-Fi for Rich Communications Services.

End-to-end encryption begins with cryptography, a method for protecting information by transforming it into an unreadable format called ciphertext. Only users who possess a secret key can decipher, or decrypt, the message into plaintext. With E2EE, the sender or creator encrypts the data, and only the intended receiver or reader can decrypt it.

While E2EE ensures that data is transferred securely between endpoints, the endpoints themselves are vulnerable to attack. Therefore, enterprises implement endpoint security to protect data beyond in-transit.