XRPL consensus freezes after removing just 12% of central nodes - but a simple tweak triples XRP defense

A new XRP Ledger study says two or three extra peer connections per participating node can sharply raise the number of nodes a targeted attack must remove to disrupt modeled consensus.

XRPL consensus depends on enough trusted validators receiving one another’s messages. A separate peer-to-peer network carries those messages between servers, so extra routes could keep validator traffic moving if an attack removes the network’s busiest hubs.

The Aug. 26 arXiv paper tests random K-out augmentation. K is the number of new undirected edges each participating node creates to peers chosen uniformly at random.

At 60% participation and K=2, the model’s quorum critical attack size rose from 11% to 38% when removals targeted the highest-degree nodes. Under an attack ordered by betweenness centrality, which prioritizes nodes that sit on many shortest paths, the threshold rose from 12% to 33%.

The second change is 2.75 times the baseline. The metric measures the simulated share of nodes removed before fewer than 80% of the model’s validators remain together in one connected component. Observed attack cost remains unknown.

At 80% and 100% participation, K=3 matched or exceeded the modeled robustness produced by roughly 20 to 25 iterations of a more invasive rewiring strategy across the paper’s network and quorum tests. K-out augmentation retained about 0.85 Jaccard similarity with the original edge set, while rewiring fell well below 0.5.