Gossipsub Network Dynamicity through GRAFTs and PRUNEs

Abstract

This network dynamicity study by Yiannis Psaras from ProbeLab analyzes GossipSub's mesh stability by investigating GRAFT and PRUNE message frequencies, session durations, and network stability through a 3.5-hour trace using the Hermes monitoring tool on Holesky testnet. The analysis reveals that despite increased dynamicity observed through GRAFT and PRUNE events, GossipSub successfully maintains stable mesh topology with the number of mesh peers per topic consistently remaining between the DLow (6) and DHigh (12) thresholds around the target of 8 peers. The study finds that 80% of peer connections are relatively short (dropping within seconds), while 10% persist for approximately 4 minutes and the remaining 10% maintain connections from 5 minutes to 1.6 hours; notably, Lodestar and Nimbus clients maintain significantly longer connection durations compared to Teku nodes, which consistently disconnect almost immediately. A notable spike in GRAFT and PRUNE events occurs during the final hour of the measurement period, with subsequent analysis identifying this as stemming from GossipSub peer scoring mechanisms responding to peers forwarding invalid messages on the voluntary_exit topic. The authors conclude that while the Hermes node observes elevated mesh connectivity dynamics, GossipSub maintains a healthy mesh structure with stable peer degrees despite these fluctuations, and the observed anomalies do not appear to impact broader network operation.