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2.1.23

Eclipse Glossary

Table of contents

Atomic composability

Composability all within the same block

Block

A group of transactions which is finalized together

Composability

The ability for one smart contract to invoke another

Consensus

Establishing the permanent order of transactions via some "voting" mechanism

Customizable rollup

A modular rollup where you can choose which component to use for functions including consensus & data availability or execution

Data availability

Ensuring blocks of data are accessible for the purpose of voting or settlement

Data availability layer

A blockchain that only performs consensus & data availability. Examples include Celestia, Polygon Avail, and Eigen DA.

Decentralization

The cost to run a full node for a blockchain

Enshrined

Performing the settlement process on another (typically Layer 1) blockchain. This is also called a "traditional rollup."

Execution

Computing the state of a blockchain by running transactions

Execution layer

A node or set of nodes for a blockchain that apply the rules for execution. This includes properties such as how gas is paid, the choice of virtual machine, and constraints on what constitutes a valid block.

Finality

The amount of time until a transaction can no longer be reordered or removed. Once a transaction has achieved finality, it is called "finalized."

Full node

A node that determines the state of the blockchain by downloading and re-executing all blocks

Honest majority

A blockchain that requires the majority of the chain to behave honestly to ensure security.

Honest minority

A blockchain that does not assume that the majority of participants are behaving honestly. An honest minority chain can be much more cost effective to run. This is also called an "M-of-N assumption."

Layer 1 blockchain

A blockchain that performs consensus. This is a layman's term which makes less sense in the context of modular blockchains. We sometimes call this a "base layer."

Layer 2 blockchain

A blockchain that relies on a Layer 1 blockchain in some way for security. This is also called a "rollup."

Layer 3 blockchain

An app-specific Layer 2 blockchain

Light node

A node that determines that state of the blockchain by relying on full nodes. This is also called a "light client."

Modular

A blockchain that shares infrastructure with other blockchains to perform one or more of the following functions: execution, consensus, data availability, or settlement. These blockchains can considerably increase their throughput and avoid typical bottlenecks.

Monolithic

A blockchain that is not modular. Examples include Solana or Aptos.

Node

A computer participating in running a blockchain network

Optimistic rollup

A rollup that does not provide any evidence of validity at the time of execution but instead allows "verifiers" to challenge a transaction execution

Permissionless

Anyone can participate in the protocol. The opposite of permissionless is "permissioned."

Scalability

The ratio of throughput to decentralization

Security

The cost to reorder or remove transactions

Settlement

Determining whether execution by a rollup was valid

Settlement layer

A blockchain that only performs settlement and bridging

Sequencer

A rollup node that proposes the initial ordering of transactions and executes the result

Sovereign

Performing the settlement process without using another blockchain. Sovereign blockchains de-couple themselves from any other blockchain.

Throughput

Transactions per second

Transaction

A request to run a program (smart contract) or send coins on a blockchain

Trust

Assumptions that need to be true in order to ensure that funds are accessible and cannot be stolen.

Trust-minimized

A rollup that adds almost no additional trust assumptions on top of the Layer 1 blockchain that it relies on.

Valid transaction

Signatures are correct and the changes to the blockchain state follow the blockchain's rules

Virtual machine

A piece of code that can run assembly code. All programs are compiled to assembly code.

Zero-knowledge rollup

A rollup that provides evidence of validity at the time of execution. This is also called a "zk-rollup."