A groundbreaking longitudinal study from the University of Cambridge's Centre for Alternative Finance (CCAF) has provided the first empirical analysis of the Bitcoin network's resilience to physical infrastructure disruption. The research, spanning 11 years of peer-to-peer network data against 68 verified submarine cable fault events, reveals a critical paradox in Bitcoin's security model.
The headline finding is that Bitcoin's network demonstrates remarkable resilience against random, large-scale physical disasters. The study's Monte Carlo simulations indicate that between 72% and 92% of the world's inter-country submarine cables would need to fail simultaneously before Bitcoin experiences significant node disconnection. Analysis of real-world events supports this: over 87% of the 68 cable faults studied caused less than a 5% impact on nodes. The largest single event—seabed disturbances off Côte d'Ivoire in March 2024 that damaged 7-8 cables simultaneously—knocked out 43% of regional internet nodes but affected only 5-7 Bitcoin nodes globally, roughly 0.03% of the network.
However, the study uncovers a severe and concentrated vulnerability in Bitcoin's infrastructure. While random cable failures require massive disruption to cause damage, a targeted attack on the cables with the highest "betweenness centrality" (critical chokepoints between continents) drops the failure threshold to just 20%. More alarmingly, targeting the top five hosting providers by node count—Hetzner, OVH, Comcast, Amazon Web Services (AWS), and Google Cloud—requires removing only 5% of routing capacity to achieve significant network impact.
This creates what researchers term "infrastructure centralization within a decentralized protocol." The vulnerability stems from economic consolidation, as running nodes increasingly moves to large-scale, cost-efficient data centers. A coordinated shutdown, DDoS attack, or regulatory action against these few providers could partition or severely degrade the network.
The research also challenges conventional thinking about TOR's impact. As of 2025, 64% of Bitcoin nodes use TOR, making their physical location unobservable. Rather than hiding fragility, the study's four-layer model found TOR adoption increases resilience by 0.02 to 0.10 on the critical failure threshold. TOR relay infrastructure is concentrated in Germany, France, and the Netherlands—countries with extensive connectivity that are among the hardest to disconnect.
The study tracks how Bitcoin's resilience has evolved over time, showing it was most resilient from 2014-2017 (threshold 0.90-0.92), declined sharply during 2018-2021 as mining concentrated in East Asia (hitting 0.72 in 2021), partially recovered to 0.88 after China's mining ban in 2021, and settled at 0.78 in 2025. This pattern demonstrates "adaptive self-organization" as the community shifted toward censorship-resistant infrastructure following events like Iran's 2019 internet shutdown and Myanmar's 2021 coup.
With current disruptions in the Strait of Hormuz highlighting infrastructure vulnerability, the Cambridge study provides crucial benchmarks for understanding Bitcoin's real-world robustness and the fundamentally different threat models posed by random failures versus targeted state or regulatory actions.
