5.1 Model and Assumptions

Firstly, we establish the network model:

• Topology: Nodes are interconnected via a P2P network.

• Maximum network delay: The network's maximum delay is denoted as D. If an honest node receives specific data in the network at time T, then other honest nodes can acquire the same data before time T + D.

Subsequently, the security model is outlined as follows:

• Detection of any invalid block is guaranteed, as at least one honest node in the network will uncover and disseminate it.

• Each honest node maintains connections with at least one other honest node.