A scaling proposal for the Ouroboros consensus family currently in research and prototyping. Where today's Ouroboros serializes block production around a per-slot, stake-weighted leader lottery (at most one block extends the chain per slot), Leios introduces parallel "input blocks" that carry transactions and "endorsement blocks" that bundle and certify them, with lower-frequency "ranking blocks" establishing the final transaction order. This lets the network pre-validate and diffuse transactions independently of the slot-leader bottleneck.
The expected payoff is significantly higher transactions per second without weakening Ouroboros's security guarantees. Leios is not deployed on mainnet today; timelines depend on the research roadmap, formal proofs, and a future hard fork.
Explore next
- OuroborosThe family of proof-of-stake consensus protocols that power Cardano, designed with formal security proofs against the known attack catalogue against PoS chains.View term
- PipeliningA protocol optimization that lets a newly produced block start propagating across the network before validation completes.View term
- BlockA unit of data containing a batch of transactions that is added to the blockchain.View term
- Proof-of-Stake AttacksThe set of known attack categories against proof-of-stake blockchains and how Cardano's Ouroboros family defends against each.View term