An infrastructure layer that replaces individual rollup sequencers with a decentralized network providing ordering-as-a-service for multiple rollups simultaneously. Shared sequencers like Espresso and Astria enable cross-rollup atomic transactions, fair MEV distribution, and reduced centralization risk by coordinating transaction ordering across rollups.
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An infrastructure layer that replaces individual rollup sequencers with a decentralized network providing ordering-as-a-service for multiple rollups simultaneously. Shared sequencers like Espresso and Astria enable cross-rollup atomic transactions, fair MEV distribution, and reduced centralization risk by coordinating transaction ordering across rollups.
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Shared Sequencing (shared-sequencing) Category: Blockchain General Definition: An infrastructure layer that replaces individual rollup sequencers with a decentralized network providing ordering-as-a-service for multiple rollups simultaneously. Shared sequencers like Espresso and Astria enable cross-rollup atomic transactions, fair MEV distribution, and reduced centralization risk by coordinating transaction ordering across rollups. Aliases: Shared Sequencer Network Related: Sequencer, Based Rollup, Rollup
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The entity responsible for ordering, batching, and submitting transactions in a Layer 2 rollup. Most rollups currently use a single centralized sequencer operated by the rollup team. Decentralized and shared sequencer designs (Espresso, Astria) distribute this power across a network of operators, enabling cross-rollup atomic composability and reducing single points of failure.
A rollup whose transaction sequencing is driven by the Layer 1 base chain's proposers rather than a dedicated centralized sequencer. L1 proposers permissionlessly include rollup blocks as part of L1 blocks, inheriting Ethereum's censorship resistance, liveness, and decentralization. The trade-off is higher latency (constrained by L1 block times), addressed through preconfirmation mechanisms.
A Layer 2 scaling technique that executes transactions off-chain, bundles them, and posts compressed data back to L1. Optimistic rollups assume transactions are valid and use fraud proofs for disputes (7-day challenge period). ZK rollups generate cryptographic validity proofs for every batch. Rollups inherit L1 security while providing 10-100x throughput improvement.
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The entity responsible for ordering, batching, and submitting transactions in a Layer 2 rollup. Most rollups currently use a single centralized sequencer operated by the rollup team. Decentralized and shared sequencer designs (Espresso, Astria) distribute this power across a network of operators, enabling cross-rollup atomic composability and reducing single points of failure.
A Layer 2 payment channel network built on Bitcoin that enables near-instant, low-cost transactions by conducting most activity off-chain. Two parties open a channel by locking BTC in a multisig transaction, then exchange signed commitment transactions off-chain; only the opening and closing transactions are broadcast on-chain. Payments can be routed across multiple channels using Hash Time-Locked Contracts (HTLCs), enabling trustless multi-hop transfers.
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The entity responsible for ordering, batching, and submitting transactions in a Layer 2 rollup. Most rollups currently use a single centralized sequencer operated by the rollup team. Decentralized and shared sequencer designs (Espresso, Astria) distribute this power across a network of operators, enabling cross-rollup atomic composability and reducing single points of failure.
A rollup whose transaction sequencing is driven by the Layer 1 base chain's proposers rather than a dedicated centralized sequencer. L1 proposers permissionlessly include rollup blocks as part of L1 blocks, inheriting Ethereum's censorship resistance, liveness, and decentralization. The trade-off is higher latency (constrained by L1 block times), addressed through preconfirmation mechanisms.
A Layer 2 scaling technique that executes transactions off-chain, bundles them, and posts compressed data back to L1. Optimistic rollups assume transactions are valid and use fraud proofs for disputes (7-day challenge period). ZK rollups generate cryptographic validity proofs for every batch. Rollups inherit L1 security while providing 10-100x throughput improvement.
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A distributed, append-only ledger that records transactions in cryptographically linked blocks. Each block contains a hash of the previous block, forming an immutable chain. Nodes in the network maintain copies of the ledger and reach agreement through consensus mechanisms. Blockchains enable trustless, decentralized record-keeping without a central authority.
The protocol by which nodes in a distributed network agree on the current state of the ledger. Common mechanisms include Proof of Work (Bitcoin), Proof of Stake (Ethereum, Solana), and BFT variants. Consensus ensures all honest nodes converge on the same transaction history despite potential network delays or malicious actors.
A consensus mechanism where validators are selected to produce blocks based on the amount of cryptocurrency they have staked (locked) as collateral. PoS is energy-efficient compared to Proof of Work. Misbehaving validators risk losing their stake (slashing). Solana, Ethereum (post-Merge), Cosmos, and Cardano use PoS variants.
A consensus mechanism where miners compete to solve computationally expensive puzzles to produce blocks and earn rewards. PoW provides strong security (51% attack resistance) but is energy-intensive. Bitcoin and pre-Merge Ethereum use PoW. The difficulty adjusts to maintain target block times regardless of total network hash power.