- **Fork Choice Rule:** [[GRANDPA Finality]] mechanism ensures deterministic finality, preventing forks once blocks are finalized. During network partitions, nodes maintain probabilistic finality through BABE while awaiting GRANDPA consensus when 2/3 connectivity is restored [109, 110]. - [[BABE Block Production]]: BABE's VRF ensures unpredictable slot leadership, using: VRF_{sk_i}(SlotNumber || EpochRandomness) → (r_i, σ_i) with ≥ 128-bit security through SR25519 signatures. - **Validator Set Updates:** Validator set changes occur at epoch boundaries (every 2400 slots), with ≈ 10% churn per epoch (e.g., 10/100 validators rotated), balancing stability and decentralization through the staking pallet's election algorithm. - **Transaction Prioritization:** The transaction pool sorts by fee per weight: Priority = Fee / Weight with configurable pool capacity. Dynamic fee adjustment based on network congestion ensures fair inclusion and prevents spam attacks through Substrate's weight-based fee model [117]. See also: [[ZKP/ZKP Base Layer/ZKP Blockchain/Technical Build Application Layer/Application Layer|Application Layer]]