Concurrency Control for Large-Scale MLS: A Hybrid Distributed Sequencer for RFC 9420
Messaging Layer Security (MLS) in RFC 9420 scales cryptographically, but overlapping group-state updates are still committed against a single epoch, and stale attempts must be retried. This is tolerable in small groups but creates avoidable delay and extra fan-out traffic in large, bursty deployments. We propose a Dece...