Gate News reports that on March 11, IBM researchers are collaborating with encrypted messaging apps Signal and Threema to design messaging systems resistant to quantum attacks. Cryptography researcher Ethan Heilman pointed out that due to the possibility of “store now, decrypt later” attacks, the recent quantum risks faced by encrypted messaging platforms may be greater than those of Bitcoin—attackers intercept and store encrypted data now, waiting for future quantum computers to become capable of cracking it. Signal has launched the PQXDH upgrade in 2023 to protect new sessions, and by 2025, the SPQR protocol upgrade will extend post-quantum protection to ongoing messages, calls, and media. Threema is working with IBM to explore integrating NIST-standardized ML-KEM algorithms into its system. The research also focuses on protecting metadata, but simply replacing existing components could lead to significant bandwidth increases, requiring a fundamental redesign of the protocol.