Skype adds support for the Signal protocol

In a move that surprised many, Microsoft and Open Whisper Systems (makers of the Signal app) announced today they are partnering to bring support for end-to-end (E2E) encrypted conversations to Skype.

The new feature, called Skype Private Conversations has been rolled out for initial tests with Skype Insider builds.

Private Conversations will encrypt Skype audio calls and text messages. Images, audio or video files sent via Skype's text messaging feature will also be encrypted.

Skype will integrate the Signal protocol

Microsoft will be using the Signal open-source protocol to encrypt these communications. This is the same end-to-end encryption protocol used by Facebook for WhatsApp and Facebook Messenger, and by Google for the Allo app.

A version of this protocol is also used by the eponymous Signal mobile IM service, Open Whisper Systems' most known product, and the favorite app of all whistleblowers, activists, dissidents, and anyone looking for an app supporting solid E2E encrypted conversations.

If Microsoft gives the go-ahead and E2E support lands in the Skype stable release, all of today's major IM platforms will be supporting encrypted conversations as optional, non-default features.

No support for Skype video calls just yet

You can test the new Skype Private Conversations feature right now by downloading and installing Skype Insider version 8.13.76.8 for Android, iOS, Linux, Mac, and Windows. Keep in mind that you won't be able to use the feature unless you're talking to another person also using a Skype Insider app.

The Skype version under testing right now does not support E2E encryption with Skype video calls or group chats.

"Give it a try by selecting “New Private Conversation” from the compose menu or from the recipient’s profile. After the recipient accepts your invite, all calls and messages in that conversation will be encrypted end-to-end until you choose to end it," explained Ellen Kilbourne, manager of the Skype Insider Program.

In other Skype news, Microsoft dropped support for Facebook sign-in today, meaning users will no longer to log into their Skype account with their Facebook credentials.