• Introduction
• Terms
• Client Registration
• Initiating Session Setup
• Receiving Session Setup
• Exchanging Messages
• Transmitting Media and Other Attachments
• Group Messages
• Call Setup
• Verifying Keys
• Transport Security
• Conclusion

This white paper provides a technical explanation of WhatsApp’s end-to-end encryption system For more information, please visit WhatsApp’s website at www whatsapp com/security

Messages between WhatsApp users are protected with an end- to-end encryption protocol so that third parties and WhatsApp cannot read them and so that the messages can only be decrypted by the recipient All types of WhatsApp messages (including chats, group chats, images, videos, voice messages and les) and WhatsApp calls are protected by end-to-end encryption

WhatsApp servers do not have access to the private keys of WhatsApp users, and WhatsApp users have the option to verify keys in order to ensure the integrity of their communication.

The Signal protocol library used by WhatsApp is Open Source, available here: https://github com/whispersystems/libsignal-protocol-java/