Quantum computers are posing a threat to the conventional encryption methods used to private messages private. Signal says it now has future-proof algorithm. — Photo: Zacharie Scheurer/dpa
NEW YORK: Right now, messages you send in messaging apps like WhatsApp, Signal and Threema are encrypted to guarantee that nobody else can read them – but what if, one day, a computer is invented that is able to go back and decrypt all of the messages you sent?
Signal, a messaging app known for its focus on user privacy, now sees itself forced to address what it calls "future quantum computing threats" and is preparing for the day when extremely powerful quantum computers could quickly crack current encryption methods.
To protect messages from these powerful computers, Signal is now updating its encryption system with an additional cryptographic component.
"This protects your communications both now and in the event that cryptographically relevant quantum computers eventually become a reality," Signal writes in a blog post.
The update sees Signal augmenting its existing so-called Double Ratchet encryption protocol with an additional layer of protection. This new layer employs a quantum-secure algorithm that has been reviewed and standardised by the US National Institute of Standards and Technology (NIST), Signal says.
The new encryption method, called Triple Ratchet, is being rolled out gradually. For users, nothing changes on the surface, however in the background, future message privacy is secured, the app says. Users don't need to do anything other than keep installing Signal updates as usual.
For now, when communicating with chat partners whose apps do not yet support the new protocol, the Double Ratchet encryption protocol will continue to be used as the common denominator. The Triple Ratchet protocol will only become the default once all users are able to adopt it. – dpa
