Rollup Nodes and Proposers

As mentioned earlier, WowChain’s Rollup nodes are essentially standard full nodes within the Layer 2 network, while Proposers are a select few among these nodes with special privileges. In WowChain, Rollup nodes and Proposers can synchronize newly added transaction data from the Sequencer using the following methods:

1. P2P Network Between Rollup Nodes

Rollup nodes form a P2P network off-chain, allowing each node to request the latest Layer 2 blocks propagated by the Sequencer from its neighboring nodes within the network. This method is optional, and Rollup nodes can choose whether or not to synchronize data via the P2P network.

2. Waiting for Sequencer to Publish on Layer 1

Rollup nodes can also wait for the Sequencer to publish the latest transaction batches (txn batches) on Layer 1, then parse the corresponding Layer 2 blocks from them. While this method is slower compared to direct synchronization through the P2P network, it offers greater censorship resistance. In scenarios where the Sequencer or most Rollup nodes isolate certain nodes, preventing them from syncing, these isolated nodes can bypass the Layer 2 network entirely and synchronize data directly from Layer 1, as long as the Sequencer regularly posts data to the Dogecoin blockchain.

State Commitments and the Role of Proposers

After a Proposer node synchronizes an ordered batch of transactions, it executes these transactions sequentially, completing the corresponding state transitions and generating a new state commitment (state root). The specific meaning and generation process of state commitments will be explained in detail later.

In brief, a state commitment is a cryptographic representation of the overall account states. Any change to an account state will result in a corresponding change to the state commitment. Each global state at a given time corresponds uniquely to a specific state commitment.

The primary responsibility of the Proposer is to publish the state commitments computed off-chain to the Dogecoin blockchain.

The Role of Proposers in WowChain

In WowChain’s design, certain Rollup nodes act as Proposers, tasked with promptly publishing the state commitments for each transaction batch (txn batch) onto the Dogecoin blockchain. This mechanism ensures the transparency, security, and finality of the Layer 2 system while maintaining strong decentralization and censorship resistance.