Delays in mempool-based blockchains under realistic conditions: case of Narwhal and DroneVet application

This study focuses on modeling and analyzing the delay in consensus protocols within mempool-based blockchains. In such systems, unconfirmed transactions are temporarily stored in a memory pool (mempool) before being selected, ordered, and committed to blocks by the consensus mechanism. In a previous work, we designed a generic model of a mempool-based blockchain, capturing core protocol behaviors. The model involves n nodes (potentially including Byzantine nodes) that exchange blocks and await one or two quorums of acknowledgments before producing new blocks and advancing to the next round. Based on this framework, we derived two Markov chains to characterize round durations and validated them through simulations. In this paper, we extend that work in three key directions: (1) We focus on Narwhal, a specific mempool protocol, describing its operations and its round duration formula. (2) We introduce DroneVet, an application leveraging UAVs to monitor livestock health and share collected data across stakeholders via blockchain technology. DroneVet is implemented using Narwhal and includes realistic environmental constraints such as packet loss, network latency, and UAV-energy limitation. (3) We develop DroneVet and compare its round duration with the theoretical round duration of Narwhal. By taking into account the environmental factors specific to agricultural deployments, this work highlights how such conditions impact the reliability and responsiveness of blockchain-based systems. Our findings provide valuable insights for deploying secure, resilient, and transparent blockchain solutions in rural settings to support reliable livestock monitoring.