Facebook announced on Friday that it is testing the ability to create “secret” conversations in its Messenger service.
The new “secret” conversations will be end-to-end encrypted, which means that Facebook will not be able to read them — or hand them over to law enforcement when they ask.
Users will also be able to apply a timer to secret conversations in Messenger, which will erase the conversation after a set period of time.
Many other messaging apps have adopted this kind of security protocol recently, including Apple’s iMessage and Facebook’s other messaging platform, WhatsApp. But one key difference is that Facebook Messenger’s encrypted conversation feature is opt-in, and doesn’t apply to all messages.
Facebook has based its messenger encryption technology on the Signal protocol, an open-source encryption protocol that’s also used to secure WhatsApp. Of course, the most imporant part of security is the details, and Facebook has released a whitepaper about its technology.
There’s one big downside to end-to-end encrypted conversations, and that’s that the increased security means it’s a lot harder to sync conversations across devices.
From Facebook’s blog post:
Starting a secret conversation with someone is optional. That’s because many people want Messenger to work when you switch between devices, such as a tablet, desktop computer, or phone. Secret conversations can only be read on one device and we recognise that experience may not be right for everyone. It’s also important to note that in secret conversations we don’t currently support rich content like GIFs and videos, making payments, or other popular Messenger features.
Faebook says that secret conversations are rolling out on a testing basis for now, with additional features coming out “this summer.”