Meta has explained how WhatsApp will preserve its end-to-end encrypted messaging while remaining interoperable with third-party messaging services.
Although accelerated by the European Union introducing its Digital Markets Act (DMA) for stricter regulation of designated messaging services, or digital "gatekeepers", WhatsApp has been developing a solution enabling third-party interoperability for two years.
Third-party providers must sign an agreement to interoperate with Messenger and WhatsApp before it can be implemented. While the company encourages using WhatsApp's Signal protocol for encryption, it will accept other protocols if they meet the same security standards.
Dick Brouwer, Engineering Director at WhatsApp, detailed in a blog post:
To interoperate, third-party providers will sign an agreement with Messenger and/or WhatsApp and we’ll work together to enable interoperability. Today we’ll publish the WhatsApp Reference Offer for third-party providers which will outline what will be required to interoperate with the service."
With the EU's new rules coming into force today, Thursday, March 7, this means that Meta “must be ready to enable interoperability with other services within three months of receiving a request", as dictated by the DMA. However, Brouwer cautions that turning on interoperability might take longer than three months before it's ready for public use.
The DMA's requirements also stipulate support for one-on-one chats and file sharing, including images, videos, or voice messages, in the initial year of the new regulation. Over time, these requirements will progressively expand to encompass group chats and calls.
How Precisely the Solution Will Work
Meta and WhatsApp stress that its approach to interoperability is "privacy-centric" and that the first step to achieving the objective is protecting the encryption protocol.
"Messenger is still rolling out E2EE (End-to-end encrypted) by default for personal communication, but on WhatsApp, this default has been the case since 2016," Meta wrote. "In both cases, we are using the Signal Protocol as the foundation for these E2EE communications, as it represents the current gold standard for E2EE chats."
To prioritise user security, Meta's preference is for third-party providers to leverage the Signal Protocol. However, ensuring compatibility for all users is critical, so Meta will permit third-party providers to employ a compatible protocol if they can demonstrate equivalent security assurances to Signal.
