Scaling glossary
Explore how crypto networks handle more activity, from rollups and layers to data availability. Follow the terms to understand the tradeoffs.
Blob
A specialized Ethereum data payload introduced for applications such as rollups, with a separate fee market and retention rules.
Bridge
A mechanism that transfers assets, asset representations or messages between blockchain environments.
Challenge period
The interval during which a submitted result or withdrawal can be disputed under a protocol's rules.
Data availability
The ability to obtain the data required to verify or reconstruct a blockchain or scaling system's state.
Fraud proof
Evidence used to demonstrate that a claimed state transition or computation is incorrect.
HTLC
Hash Time Locked Contract: a conditional payment combining a hash-secret requirement with a timeout.
Layer 1
A blockchain's base network, responsible for its own consensus and canonical state.
Layer 2
A system that processes activity outside a base blockchain while relying on it for key security or settlement functions.
Lightning Network
A Bitcoin payment network using channels to transfer value without recording every payment onchain.
Optimistic rollup
A rollup that initially accepts submitted execution results subject to a mechanism for challenging invalid results.
Payment channel
A channel that permits participants to update payment balances without an onchain transaction for every payment.
Rollup
A scaling system that executes transactions separately and publishes the required data and commitments to a base chain.
Sequencer
A component or participant that orders transactions for execution in a scaling system.
Sidechain
A separate blockchain connected to another chain but using its own consensus security.
State channel
A system in which participants exchange authorized state updates offchain and use a blockchain to enforce settlement.
Validity proof
A cryptographic proof showing that a claimed computation or state transition follows the specified rules.
Validium
A scaling design that uses validity proofs while storing transaction data outside the settlement chain.
Zero-knowledge rollup
A rollup that uses cryptographic validity proofs to demonstrate correct execution of transaction batches.
Looking for an earlier definition? Explore the original collection
Concept entries explain ideas. Our separate asset registry identifies coins, tokens and networks by source metadata. Sources & standards