Until now, using WhatsApp web on your desktop or any other device has required having a phone that’s powered on and connected, but a new beta test is trying out support for multiple devices without needing a phone in the mix. In a June interview, WhatsApp head Will Cathcart and his boss, Facebook CEO Mark Zuckerberg, commented on the technical challenge of maintaining end-to-end encryption. With a blog post today, Cathcart explains more about what has been done behind the scenes to maintain security.
:no_upscale()/cdn.vox-cdn.com/uploads/chorus_asset/file/22718057/whatsapp_e2e.jpg)
As the image comparing the legacy and new systems (above) tries to explain, previously, a user’s phone managed the key determining their identity and ability to encrypt/decrypt messages. The encrypted synchronization also applies to message history, contact names, and other data, with keys maintained on the individual devices.
To start, the beta is going out to a limited group of testers who are already in WhatsApp’s beta program, while the team says it’s working on improving performance and adding more features.
We’ve been working on this for a long time. Until now, @WhatsApp has only been available on one device at a time. And desktop and web support only worked by mirroring off your phone – which meant your phone had to be on and have an active internet connection.
— Will Cathcart (@wcathcart) July 14, 2021
