{"guid":"a4646b1e-7e09-55e9-8e7d-b30a4379ced9","title":"MatrixRTC - The key sharing problem","subtitle":null,"slug":"matrix-conf-2025-81420-matrixrtc-the-key-sharing-problem","link":"https://cfp.2025.matrix.org/matrix-conf-2025/talk/QCYBMC/","description":"Why is having large encrypted group calls difficult? How do other providers solve this? The future? Demos!\n\nWhy are large encrypted group calls difficult to host? Specifically, we will go into the details about key sharing, how we can use some tricks to optimize it and how they are also a very big footgun.\n\nWe will also see how other providers like jitsi, zoom, discord and cloudflare handle this. 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