Summary
- Code and flags related to MLS, codenamed “Zinnia,” have been discovered within the latest Google Messages beta (v20250106_00_RC00), indicating active integration of the new encryption standard.
- Testers were able to activate MLS encryption for individual conversations, but group chat support still seems to be missing.
- The development signifies progress towards interoperable end-to-end encryption across different messaging platforms, contingent on other platforms adopting MLS as well.
Google Messages has quietly become one of the best messaging platforms for Android users. From support for RCS that enables key features like read receipts, typing indicators, encryption, and more, to its tight integration with the overarching Android and Google ecosystem, like integration with Gemini AI.
Back in 2023, Google announced that Google Messages had reached the 1 billion active RCS user milestone, and that number has only grown since then, especially considering that Google Messages come pre-installed on most Android phones. Back in 2023 was also when Google first pledged support for Messaging Layer Security (MLS), and we’re now starting to see the first signs of the integration on the app.
MLS is the Internet Engineering Task Force’s (IETF) standard for end-to-end encryption. Google has previously been spotted working on integrating the standard, potentially as a replacement or to complement the current Signal Protocol on top of the RCS Universal Profile that it uses to implement E2EE. If other messaging services follow suit and adopt the protocol, the end result will be better interoperability across the board, including cross-platform RCS E2EE between Android and iOS devices, even within group chats.
GSMA, the industry body that oversees RCS Universal Profile, has previously confirmed that the next major milestone for the protocol will be to introduce interoperable encryption between cross-platform RCS chats — and while we’re uncertain how much progress has been made there, folks over at Android Authority have been able to spot, and even enable, MLS on Google Messages.
Still a long road ahead
According to the report, flags for the existence of MLS within the app were found in the latest Google Messages 20250106_00_RC00 beta, highlighting the ‘Zinnia’ codeword for the standard within the app. Fiddling with the flag enabled it for one-to-one chats, which was confirmed by observing the encryption protocol’s value in code. A value of 0 signifies that the default RCS encryption is in use while the value 1, as seen in the second screenshot above, indicates that MLS is active.
The functionality isn’t publicly available yet, and even after fiddling with connected flags, MLS could not be enabled for group chats, which is likely the next in line to be polished and finalized. The exact timeline for MLS’ public availability within Google Messages currently remains clear. And even if support rolls out relatively quickly, the standard won’t truly shine until other messaging platforms also start adopting it.
