WhatsApp will provide end-to-end encryption for chat backups: Zuckerberg

Facebook founder and CEO Mark Zuckerberg said Friday that WhatsApp has built end-to-end encrypted backups and will soon begin rolling out this extra layer of privacy and security protection to users.

"We’re adding another layer of privacy and security to WhatsApp: an end-to-end encryption option for the backups people choose to store in Google Drive or iCloud. WhatsApp is the first global messaging service at this scale to offer end-to-end encrypted messaging and backups, and getting there was a really hard technical challenge that required an entirely new framework for key storage and cloud storage across operating system," Zuckerberg said in a post on his Facebook page.

WhatsApp has more than 2 billion users globally and over 400 million in India. These users send more than 100 billion messages a day.

Encryption is the practice of scrambling data to make it unintelligible for even the service providers. It keeps conversations private, and end-to-end encryption means only the intended sender and receiver can see the messages being sent.

A major issue and question with WhatsApp's chat backups was that these are stored with third party cloud providers like Google (Drive) or iCloud.

"Prior to the introduction of end-to-end encrypted backups, backups stored on Apple iCloud and Google Drive were not protected by WhatsApp’s end-to-end encryption. Now we are offering the ability to secure your backups with end-to-end encryption before they are uploaded to these cloud services," WhatsApp said in a whitepaper explaining the technology behind this new update.

It further explained, "With end-to-end encrypted backups enabled, before storing backups in the cloud, the client encrypts the chat messages and all the messaging data (i.e. text, photos, videos, etc) that is being backed up using a random key that’s generated on the user’s device. The key to encrypt the backup is secured with a user-provided password. The password is unknown to WhatsApp, the user’s mobile device cloud partners, or any third party."

WhatsApp will be releasing this as an optional feature and in the coming weeks we will be rolling this out to iOS and Android users.

To enable end-toend encrypted backups, WhatsApp developed an entirely new system for encryption key storage that works with both iOS and Android.

When the account owner uses a personal password to protect their end-to-end encrypted backup, the new technology built by WhatsApp will store the key and safeguard it by registering it with the Backup Key Vault.

When someone wants to retrieve their backup:

• They enter their password, which is encrypted and then verified by the Backup Key Vault.
• Once the password is verified, the Backup Key Vault will send the encryption key back to the WhatsApp client.
• With the key in hand, the WhatsApp client can then decrypt the backups.
• Alternatively, if an account owner has chosen to use the 64-digit key alone, they will have to manually enter the key themselves to decrypt and access their backups