💡What is Shared Sequencing?

Overview

Shared Sequencing separates the sequencing and execution of transactions. This allows different execution layers to all use the same shared sequencer and allows rollups to focus on their execution layer. The shared sequencer sequences the transactions and orders all of them into a singular block which can contain transactions from multiple rollups. After this block has been finalized on the SEQ L1, the rollup's execution layer can easily execute the transactions in the same order it received them from the SEQ L1. After this, the rollup will submit the transactions to a data availability layer and/or settlement layer.

Why does this matter?

Shared sequencers offer several advantages for rollups

• It reduces the complexity to launch a rollup. With the SDK we provide it will be easy for rollups to integrate with the SEQ L1. The end-user should never have to worry about the SEQ L1 at all.

• Cross-rollup interoperability made simple. When you are using the same sequencer across many different rollups it is easy for the user/rollups to make a transaction dependent on the inclusion of a transaction from a different rollup. You can even do this across different execution layers which could lead to some very interesting uses of bridges.

• Using a shared sequencer decreases the cost of decentralization. Currently decentralizing a rollup's sequencer requires each and every rollup to bootstrap an entire validator set which takes time and can cost quite a bit. At the end of the day, rollups should be able to focus on their execution layer which is what matters most to users.