Skype's incoming end-to-end protection, dubbed Private Conversations, safeguards audio calls, text messages and shared files.
Several popular services have added encrypted messaging for their products, such as WhatsApp and Facebook Messenger, while other apps like Threema specialize in it. Skype, despite its popularity, has been slow to offer its users this option. Microsoft is using the Signal Protocol by Open Whisper Systems to secure the data and for now, you can only use this feature with contacts that are participating in the Skype Insider Preview. The feature is not supported in group chats.
During the preview, users only will be able to start private conversations with other Skype Insiders using the latest preview version, and interactions will be limited to one-to-one conversations. You will be taken to a new chat with them. A new invitation must be sent and accepted, to change to another device.
Then an invite will be sent to that person to join - this is valid for seven days, after which it expires and you'll need to send another one.
In order to further protect privacy, Private Conversations will not be shown in Chats or in any form of notification. You can do that by right-clicking on the conversation and selecting Delete chat.
Microsoft has bunged end-to-end encrypted communications into beta versions of Skype using the open-source Signal protocol.
A Private Conversation will have a lock icon next to your contact's name. Microsoft does hand over some people's details and chat logs where "legally required and technically feasible", Mark Gillett, the company's chief operating officer said at the time. End-to-end encryption will be provided for text messages, audio calls, as well as several types of files.
Skype Private Conversations give users enhanced security with end-to-end encryption.