How does end-to-end encryption work in WhatsApp - briefly?
End-to-end encryption in WhatsApp ensures that only the sender and recipient can read messages. This is achieved by generating a unique lock for each message, which only the intended recipients have the special key to unlock.
How does end-to-end encryption work in WhatsApp - in detail?
End-to-end encryption (E2EE) is a security feature that ensures only the communicating users can read messages, preventing third parties, including WhatsApp itself, from accessing the content of communication. Here's how it works in detail:
When you send a message on WhatsApp, it first passes through the WhatsApp server but remains encrypted. The encryption process involves two keys: a public key and a private key. Each user has their own pair of these keys. The public key can be freely distributed, while the private key must remain secret.
- Key Generation: When you create an account or reinstall WhatsApp, your device generates a new pair of keys. The public key is sent to WhatsApp's servers and stored there for delivery to other users. Your private key remains on your device.
- Message Encryption: Before sending a message, WhatsApp retrieves the recipient's public key from its server. It then uses this public key to encrypt the message. This encryption process ensures that only the intended recipient can decrypt and read the message.
- Message Delivery: The encrypted message is sent through WhatsApp's servers to the recipient's device. At this point, even WhatsApp cannot read the content of the message because it is encrypted with the recipient's public key.
- Message Decryption: Once the message reaches the recipient's device, their private key is used to decrypt the message. This process allows only the intended recipient to read the message, ensuring that the communication remains secure and confidential.
- Forward Secrecy: WhatsApp also employs a technique called "forward secrecy." This means that even if your private key is compromised in the future, past messages cannot be decrypted using it. Each message has its own unique encryption key, derived from the public keys of both parties and the message itself.
- Verification: To ensure that no one is intercepting your communication, WhatsApp allows users to verify each other's security codes. This code is a hash of the user’s public key, and comparing these codes helps confirm that the conversation is end-to-end encrypted.
In summary, WhatsApp's end-to-end encryption ensures that only you and the person you're communicating with can read what is sent, and nobody in between, not even WhatsApp. This provides a robust layer of security for users' conversations.