Rollup Node

[frisitano]

Overview

We should implement a rollup node that is responsible for driving the reth execution client via the engine API.

Rollup Node Functionality

• verify that L1 messages are correctly ordered and included in blocks.
• Gossip the latest blocks over it's p2p network.
• validate consensus of blocks (assert the block was produced by the authorised sequencer)
• Feed L2 block to reth execution client via engine API
• Sync batches from L1 and determine finality of blocks
• Issue fork choice updates via engine api

[greged93]

Below is a (very) high level overview of the design we can adopt for the RN. The idea is to keep the RN as a task running in the Reth process, allowing us to reuse the P2P network from the EL, all the while keeping a clear boundary of the RN, which would allow for easy extraction of the RN as a separate process if this is ever desired.

We leverage the NetworkManager, removing the block propagation PoS gate, allowing us to propagate the blocks. The NetworkManager contains a block_import field which allows to define a hook when the network imports a new block. This hook would send the block to the RN via a channel and return the result of the validation by the RN.

The RN can then decide to call the Engine API via a client.