@@ -17,27 +17,27 @@ and endorser blocks (EBs) that validate them, enhancing the network’s capacity
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Leios offers several significant advantages:
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- - ** Higher throughput and lower latency. ** By splitting transaction processing
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+ - ** Higher throughput and lower latency: ** by splitting transaction processing
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into IB and EB stages, Leios handles more transactions in parallel, enabling
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- faster and more responsive applications.
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- - ** Better user experience. ** Faster transaction processing means quicker
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- confirmations for wallet users and dApp interactions.
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- - ** Flexible diffusion strategies. ** Nodes can choose how to share blocks (e.g. ,
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- prioritizing newest or oldest data), optimizing network performance based on
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- conditions.
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- - ** Enhanced cryptography. ** Leios uses Boneh–Lynn–Shacham (BLS) signatures for
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+ faster and more responsive applications
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+ - ** Better user experience: ** faster transaction processing means quicker
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+ confirmations for wallet users and DApp interactions
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+ - ** Flexible diffusion strategies: ** nodes can choose how to share blocks (eg ,
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+ prioritizing the newest or the oldest data), optimizing network performance based on
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+ conditions
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+ - ** Enhanced cryptography: ** Leios uses Boneh–Lynn–Shacham (BLS) signatures for
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aggregated verification and verifiable random functions (VRFs) for fair leader
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- selection.
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- - ** Robust simulations and formal methods. ** Rust and Haskell simulations
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+ selection
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+ - ** Robust simulations and formal methods: ** Rust and Haskell simulations
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measure real-world performance, and executable specifications ensure
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- correctness.
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- - ** Scalable cost model. ** A cost calculator helps node operators estimate
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- expenses (e.g. , storage, CPU usage).
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+ correctness
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+ - ** Scalable cost model: ** a cost calculator helps node operators estimate
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+ expenses (for example , storage and CPU usage).
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- ## What does Leios mean for Cardano users (e.g. , wallet users, dApp developers)?
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+ ## What does Leios mean for Cardano users (eg , wallet users, DApp developers)?
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For everyday users, Leios means faster transaction confirmations and a smoother
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- experience in wallets and dApps —think near-instant payments or interactions
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+ experience in wallets and DApps —think near-instant payments or interactions
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instead of waiting 20 seconds or more. For developers, it offers higher
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throughput (more transactions per second), enabling complex, high-volume
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applications like decentralized exchanges or gaming platforms. However, wallets,
@@ -47,21 +47,21 @@ EBs, RBs), so expect some transition as it rolls out.
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## What are the risks or trade-offs of Leios?
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Leios prioritizes scalability, but it’s not without trade-offs. Parallel
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- processing increases demands on node operators (e.g. , more CPU, bandwidth,
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+ processing increases demands on node operators (eg , more CPU, bandwidth,
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storage), potentially raising costs or requiring better hardware. The complexity
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- of three block types (IBs, EBs, RBs) could also introduce new bugs or delays
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+ of the three block types (IBs, EBs, RBs) could also introduce new bugs or delays
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during implementation. However, extensive simulations and formal methods aim to
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minimize these risks, ensuring Leios remains secure and reliable as it matures.
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## What are IBs, EBs, and RBs in Leios?
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Leios uses three distinct block types:
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- - ** IB (input block): ** a block that contains transactions. Produced by nodes
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+ - ** IB (input block)** . A block that contains transactions. Produced by nodes
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that win the IB sortition lottery.
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- - ** EB (endorser block): ** a block that references one or more IBs, providing
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+ - ** EB (endorser block)** . A block that references one or more IBs, providing
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endorsements. Produced by nodes that win the EB sortition lottery.
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- - ** RB (ranking block): ** a block that ranks or orders other blocks as part of
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+ - ** RB (ranking block)** . A block that ranks or orders other blocks as part of
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the consensus mechanism.
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Each block type plays a distinct role in moving transactions from submission to
@@ -70,42 +70,46 @@ occur every ~20 seconds.
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## What is the relationship between Ouroboros, Peras, and Leios?
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- ### Ouroboros: The Foundation
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+ ### Ouroboros: the foundation
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- What it is: Ouroboros is the overarching family of proof-of-stake (PoS)
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consensus protocols that powers Cardano. It’s designed to be secure,
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energy-efficient, and provably fair, replacing proof-of-work (PoW) systems
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like Bitcoin’s.
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- - Key Features :
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+ - Key features :
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- Slot-based time division (epochs and slots, with slots typically 1 second
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- long in earlier versions, now 20 seconds in Praos for block production).
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- - Stake pool leaders elected based on stake to mint blocks.
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- - Formal mathematical proofs of security (e.g. , resistance to attacks like
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- double-spending or chain forks).
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+ long in earlier versions, now 20 seconds in Praos for block production)
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+ - Stake pool leaders elected based on stake to mint blocks
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+ - Formal mathematical proofs of security (for example , resistance to attacks like
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+ double-spending or chain forks)
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- Role: Ouroboros is the bedrock consensus mechanism that Peras and Leios build
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upon or refine.
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- ### Peras: A Modular Upgrade
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+ ### Peras: a modular upgrade
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- What it is: Peras is a proposed evolution of Ouroboros aimed at improving
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efficiency and modularity.
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- - Key Features :
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- - Separation of Concerns: Peras splits consensus into modular components, such
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+ - Key features :
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+ - Separation of concerns. Peras splits consensus into modular components, such
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as transaction ordering, validation, and ledger state updates, to allow
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parallel processing and flexibility.
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- - Improved Finality: It introduces mechanisms for faster confirmation times,
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+ - Improved finality. It introduces mechanisms for faster confirmation times.
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+ - Separation of concerns. Peras splits consensus into modular components, such
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+ as transaction ordering, validation, and ledger state updates to allow
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+ parallel processing and flexibility.
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+ - Improved finality. It introduces mechanisms for faster confirmation times,
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potentially reducing the time to finality compared to Praos’ 20-second block
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intervals.
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- - Adaptability: Designed to integrate with future scaling solutions (like
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+ - Adaptability. Designed to integrate with future scaling solutions (like
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Leios) and sidechains or layer-2 systems.
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- Relationship to Ouroboros:
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- Peras is a direct descendant of Ouroboros Praos, refining its mechanics
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- while staying within the PoS framework. It’s like an “ Ouroboros 2.0,”
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+ while staying within the PoS framework. It’s like an ' Ouroboros 2.0,'
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optimizing the core protocol without fundamentally changing its PoS nature.
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- It serves as a bridge between the foundational Ouroboros Praos and more
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radical scalability-focused variants like Leios.
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- ### Leios: A Scalability Leap
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+ ### Leios: a scalability leap
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- What it is: Ouroboros Leios is a specific variant of the Ouroboros family,
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designed to dramatically increase Cardano’s throughput (transactions per
@@ -114,43 +118,43 @@ occur every ~20 seconds.
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research community.
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- Relationship to Ouroboros:
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- Leios is a specialized extension of Ouroboros, taking the core PoS mechanics
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- and rearchitecting block production for scalability.
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+ and re-architecting block production for scalability.
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- It retains Ouroboros’ security model but reimagines how transactions are
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ingested and validated, making it a next-generation Ouroboros variant.
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- ### The Relationship
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+ ### The relationship
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- - Ouroboros as the Core :
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+ - Ouroboros as the core :
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- Ouroboros (especially Praos) is the foundational consensus protocol that
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defines Cardano’s PoS system. Both Peras and Leios are built on this
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foundation, inheriting its security properties and stake-based governance.
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- - Peras as an Intermediate Step :
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+ - Peras as an intermediate step :
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- Peras enhances Ouroboros by introducing modularity and efficiency
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improvements, potentially laying the groundwork for integrating advanced
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features like those in Leios. It’s a stepping stone that refines Praos’
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mechanics, making it more adaptable to future needs.
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- - Leios as a Scalability Solution :
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+ - Leios as a scalability solution :
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- Leios takes Ouroboros further by addressing throughput limitations head-on.
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It uses the same PoS principles but introduces a parallel processing model
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that Peras’ modularity could theoretically support or complement.
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- - Leios can be seen as a “ plugin” or evolution that fits into the Ouroboros
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+ - Leios can be seen as a ' plugin' or evolution that fits into the Ouroboros
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ecosystem, possibly relying on Peras’ groundwork for smoother integration.
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- - Timeline and Evolution :
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- - Ouroboros Praos → Current live protocol
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- - Peras → A near-future refinement for flexibility and efficiency
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- - Leios → A long-term scalability solution, still in research/development,
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+ - Timeline and evolution :
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+ - Ouroboros Praos → current live protocol.
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+ - Peras → a near-future refinement for flexibility and efficiency.
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+ - Leios → a long-term scalability solution, still in research/development,
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aimed at making Cardano competitive with high-TPS blockchains like Solana or
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- Ethereum layer-2s
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+ Ethereum layer-2s.
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## What's the state of an IB before an EB or RB gets created for it? Is it visible, is it usable?
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- Before an Endorsement Block (EB) or Ranking Block (RB) is created, an Input
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- Block (IB) is a proposed set of transactions in a preliminary state. Here’s what
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+ Before an endorsement block (EB) or ranking block (RB) is created, an input
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+ block (IB) is a proposed set of transactions in a preliminary state. Here’s what
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that means:
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- ### State of an Input Block
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+ ### State of an IB
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- An IB is minted by a node (e.g. , a stake pool operator) and contains unconfirmed
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+ An IB is minted by a node (eg , a stake pool operator) and contains unconfirmed
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transactions from the mempool. It’s cryptographically signed for authenticity
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but hasn’t been validated or finalized by the network, leaving it in a pending
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state.
@@ -159,12 +163,12 @@ state.
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Once minted, the IB is broadcast and visible to all nodes. This allows them to
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inspect its transactions and start validation, a key part of Leios’ parallel
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- processing design. However, visibility doesn’t mean it’s accepted— it’s just a
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+ processing design. However, visibility doesn’t mean it’s accepted — it’s just a
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proposal.
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### Usability
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- The IB isn’t usable yet— its transactions can’t be spent or relied upon because
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+ The IB isn’t usable yet — its transactions can’t be spent or relied upon because
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they lack consensus and finality. Only after EBs endorse it and an RB finalizes
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it does it become part of the blockchain’s official state. Until then, it could
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still be discarded if it fails validation.
@@ -174,36 +178,34 @@ still be discarded if it fails validation.
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Leios boosts performance by processing transactions in parallel, even though
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final confirmation still takes 20 seconds. Here’s how:
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- ### Parallel Processing Boost
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+ ### Parallel processing boost
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- Think of Leios like a factory: In Ouroboros Praos, one worker (a slot leader)
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+ Think of Leios like a factory: in Ouroboros Praos, one worker (a slot leader)
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builds a block every 20 seconds. In Leios, dozens of workers (nodes) create
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- Input Blocks (IBs) continuously, others check them with Endorsement Blocks
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- (EBs), and a supervisor (Ranking Block, RB) approves the batch every 20 seconds.
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+ IBs continuously, others check them with EBs, and a supervisor (RB) approves the batch every 20 seconds.
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This parallelism lets the network handle far more transactions in that
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- time— potentially 10x to 100x more than Praos.
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+ time — potentially 10x to 100x more than Praos.
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- ### Splitting the Work
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+ ### Splitting the work
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- - ** IBs** : Propose transactions frequently and in parallel.
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- - ** EBs** : Validate IBs concurrently across nodes.
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- - ** RBs** : Finalize everything every 20 seconds, ensuring security. Unlike
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+ - ** IBs** . Propose transactions frequently and in parallel.
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+ - ** EBs** . Validate IBs concurrently across nodes.
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+ - ** RBs** . Finalize everything every 20 seconds, ensuring security. Unlike
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Praos, where one block does it all, Leios splits these roles so transaction
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processing isn’t bottlenecked by the 20-second RB interval.
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- ### Practical Gains
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+ ### Practical gains
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While IBs aren’t spendable until an RB confirms them, EBs provide early
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confidence, letting apps (like wallets) act on them sooner for low-risk tasks
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- (e.g. , showing balances). The 20-second RB is a security anchor, not a
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+ (for example , showing balances). The 20-second RB is a security anchor, not a
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limit—hundreds of IBs can queue up in that window, massively increasing
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throughput.
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## How does Leios maintain security with parallel processing?
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Leios preserves Cardano’s strong security by combining parallel transaction
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- processing with a sequential finality layer. Input Blocks (IBs) and Endorsement
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- Blocks (EBs) are produced in parallel, but Ranking Blocks (RBs) finalize the
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+ processing with a sequential finality layer. IBs and EBs are produced in parallel, but RBs finalize the
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ledger every 20 seconds, ensuring a single, consistent chain. This prevents
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double-spending or forks by resolving conflicts at the RB stage. Additionally,
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cryptographic tools like BLS signatures and VRFs ensure that only valid blocks
@@ -214,9 +216,9 @@ guarantees.
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Leios finalizes blocks through a structured voting mechanism. Nodes may adopt:
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- - ** Single-stage voting: ** all votes are broadcast in one phase, possibly
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- resulting in a longer CPU usage 'tail' during high throughput.
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- - ** Send-recv (two-stage) voting: ** votes are first sent, then a follow-up
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+ - ** Single-stage voting** : all votes are broadcast in one phase, possibly
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+ resulting in a longer CPU usage 'tail' during high throughput
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+ - ** Send-recv (two-stage) voting** : votes are first sent, then a follow-up
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receive phase ensures broader propagation before final tallies.
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You can configure voting through parameters such as leios-vote-send-recv-stages
@@ -233,9 +235,9 @@ sortition' because once a node proves it was selected to produce a block or vote
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Leios supports multiple strategies for propagating blocks and votes:
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- - ** Oldest-first: ** prioritizes older blocks or transactions
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- - ** Freshest-first: ** focuses on the newest blocks or transactions first
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- - ** Peer-order: ** requests blocks in the order peers announce them.
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+ - ** Oldest-first** : prioritizes older blocks or transactions
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+ - ** Freshest-first** : focuses on the newest blocks or transactions first
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+ - ** Peer-order** : requests blocks in the order peers announce them.
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Your choice of strategy can affect latency, network load, and overall
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throughput.
@@ -253,11 +255,11 @@ sharding, but it is not yet part of Leios.
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Leios incorporates multiple cryptographic techniques to ensure security and
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efficiency:
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- - BLS signatures: allows efficient aggregation of many signatures into one,
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+ - BLS signatures: allow efficient aggregation of many signatures into one,
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reducing verification overhead
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- Mithril or Musen protocols: used for voting and proof aggregation, depending
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on the context
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- - VRFs: ensures fair selection of nodes for block production
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+ - VRFs: ensure fair selection of nodes for block production.
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Recent benchmarking shows that aggregated BLS verification significantly speeds
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up certificate validation.
@@ -290,11 +292,11 @@ Developers continually refine these simulations based on real-world data.
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Based on preliminary internal testing and simulations:
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- - ** Block size: ** commonly set to about one-third of the available link capacity
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+ - ** Block size** : commonly set to about one-third of the available link capacity
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for IBs
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- - ** Voting stages: ** choose single-stage or send-recv, depending on reliability
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+ - ** Voting stages** : choose single-stage or send-recv, depending on reliability
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and speed requirements
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- - ** Diffusion strategy: ** many operators use 'freshest-first,' though
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+ - ** Diffusion strategy** : many operators use 'freshest-first,' though
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'peer-order' may help maintain compatibility with older setups.
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Operators can adjust these parameters, which evolve through community votes.
@@ -306,7 +308,7 @@ You can follow:
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- Weekly updates on the Ouroboros Leios site
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- Technical reports for deeper insights
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- Leios glossary for definitions of commonly used terms
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- - Public GitHub repositories that host source code and simulations
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+ - Public GitHub repositories that host source code and simulations.
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These resources provide transparency and regular updates on ongoing development.
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@@ -315,9 +317,9 @@ These resources provide transparency and regular updates on ongoing development.
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Leios changes how transactions are validated and how blocks and memory pools
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operate, potentially affecting:
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- - ** Wallets and SDKs, ** which need to accommodate new block types (IBs and EBs)
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- - ** Explorers, ** which must handle higher throughput and multi-block referencing
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- - ** Indexers and APIs, ** which will see more granular block and vote data.
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+ - ** Wallets and SDKs** , which need to accommodate new block types (IBs and EBs)
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+ - ** Explorers** , which must handle higher throughput and multi-block referencing
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+ - ** Indexers and APIs** , which will see more granular block and vote data.
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Weekly updates provide a deeper analysis of these topics, including how advanced
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indexing and potential sharding solutions might eventually mitigate challenges.
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