Pando: Extremely Scalable BFT Based on Committee Sampling
Xin Wang
Network and Distributed System Security (NDSS) Symposium 2026 · Day 1 · Distributed Systems
This talk presents **Pando**, a Byzantine Fault Tolerant (BFT) consensus protocol that achieves extreme scalability by **decoupling block data transmission from consensus ordering** and using **committee sampling** to reduce communication complexity. While existing BFT protocols have been evaluated with at most 100-200 nodes, Pando successfully scales to **1,000 replicas** -- more than four times the previous state-of-the-art -- while delivering approximately **70,000 transactions per second**. The protocol achieves **O(kappa) communication complexity** where kappa is a security parameter independent of network size, maintaining security against **weakly adaptive adversaries** under partial synchrony.
AI review
A distributed systems/blockchain consensus paper that scales BFT to 1,000 nodes using committee sampling. Technically competent with solid Chernoff bound analysis, but this is a consensus protocol paper, not security research. No novel attack technique, no vulnerability discovery, no offensive capability. The Q&A exposed uncertainty about whether probabilistic safety guarantees hold across many epochs -- a fundamental question that the speaker couldn't fully address.