Sequencer
The party or system that orders transactions on a Layer 2 rollup before they're posted to the base chain.
A sequencer is responsible for receiving, ordering, and initially processing transactions on a Layer 2 rollup, before that transaction data is eventually posted back to the underlying base chain.
Many rollups currently operate with a single, centralized sequencer, a real, documented centralization point that a number of projects are actively working to decentralize.
Examples
- A rollup's sequencer being temporarily offline can prevent new transactions from being processed on that network.
- Decentralizing the sequencer role is an active area of development across many Layer 2 projects.
Learn more
The Layer 2 Scaling Landscape
Read the research article
Based Rollup
Read the Based Rollup glossary definition
Forced Inclusion
Read the Forced Inclusion glossary definition
Rollup-as-a-Service (RaaS)
Read the Rollup-as-a-Service (RaaS) glossary definition
Censorship Resistance
Read the Censorship Resistance glossary definition