Shoal++ - High Throughput DAG BFT Can Be Fast and Robust

Learn about Shoal++, a novel DAG-based Byzantine Fault Tolerant consensus system that bridges the gap between low latency and high throughput in this 16-minute conference presentation from NSDI '25. Discover how researchers from Aptos Labs, Cornell University, and UIUC developed a solution that addresses the traditional trade-off in BFT consensus protocols where systems either optimize for latency (like PBFT with 3 message delays but limited throughput due to single leader bottlenecks) or throughput (like DAG-BFT protocols that achieve scalability but require 10.5 message delays on average). Explore the technical innovations behind Shoal++ that achieves the throughput benefits of DAG-based systems while reducing end-to-end consensus commit latency to an average of 4.5 message delays. Examine the empirical results demonstrating that Shoal++ delivers throughput comparable to state-of-the-art DAG BFT solutions while reducing latency by up to 60%, even under challenging network conditions and failure scenarios. Understand how this system separates data dissemination from consensus and utilizes every replica as a proposer to achieve both speed and robustness in distributed consensus protocols.