Google’s Messages app may get cross-platform chat encryption in the future. The company is announcing its adoption of an end-to-end encryption system known as Messaging Layer Security, or MLS. This will allow Google’s platform to connect and exchange messages with external messaging apps that also support MLS (via 9to5Google,
Do you want to message a group chat and display it securely and seamlessly on other people’s devices in their favorite chat apps? This is the future European regulators are pushing for: for tech companies to implement an end-to-end encryption system that allows users to securely send messages between platforms.
Meaningful interoperability will require major companies to support the same standard, and it looks like MLS is now one of the biggest on its side. Google also supports a carrier-supported end-to-end encrypted messaging system called RCS. For a while, RCS didn’t have proper security for group chats, but Google is now releasing a version that does (that doesn’t use MLS).
One big problem that MLS could solve is better encryption for group messages. An Oxford paper published in 2017 pointed to security concerns over how some major messaging apps including WhatsApp, Facebook Messenger and Google Allo (RIP) can intercept group messages if only one member is compromised. So the researchers designed an “asynchronous ratcheting tree” that makes end-to-end group messages even more secure, and MLS was built with that idea in mind.
The MLS protocol is developed by a standards organization called the Internet Engineering Task Force (IETF). The body approved the publication of the MLS specification (RFC 9420) in March and has previously tested draft versions in Webex and RingCentral chat.
Google is moving toward open sourcing its MLS implementation into Android’s codebase, but hasn’t said when that will happen. It also did not specify whether or not RCS messaging, which Google has supported externally for more than a year, would work with MLS-based encryption. Google continues to shame Apple for not supporting RCS, which is now available to over 800 million Android users. It remains to be seen whether other tech companies will “get the message” from MLS.
