Bitcoin and Submarine Cables: Cambridge Research Reveals the Network's True Resilience

A new study by the Cambridge Alternative Finance Center shows that the Bitcoin network is much more resilient to underwater infrastructure than it appears. The research indicates that almost all submarine cables worldwide would need to fail simultaneously, whereas Bitcoin’s actual vulnerabilities could be exploited through targeted attacks.

By analyzing 11 years of peer-to-peer network data and 68 real-world submarine cable failure events, the researchers assessed the physical infrastructure resilience of the Bitcoin blockchain. The key finding is that for a major network node disconnection to occur, between 72% and 92% of intercontinental submarine cables would have to fail at the same time.

How much of a threat are random submarine cable failures in reality?

In 1,000 Monte Carlo simulations, random submarine cable failures had virtually no impact on the Bitcoin network. Over 87% of the 68 real incidents studied resulted in node effects below 5%.

Even the largest single event in March 2024, which damaged 7-8 submarine cables off the coast of Ivory Coast, affected only about 0.03% of Bitcoin nodes globally. Interestingly, a correlation of -0.02 was found between submarine cable failures and Bitcoin price, indicating that infrastructure outages practically leave no trace in market movements.

Targeted attacks: A very different threat scenario

The most striking finding is the huge difference between random submarine cable failures and deliberate attacks. While random failures require a 72-92% cable cut to impact the network, targeting the most connected submarine cables that serve as bottlenecks between continents can reduce this threshold to just 20%.

Even more surprising is the scenario for hosting providers. Attacking just five major providers—Hetzner, OVH, Comcast, Amazon, and Google Cloud—would require disabling only 5% of routing capacity to produce the same effect. This clearly illustrates two very different threat models facing Bitcoin: the first involves natural, random failures, which Bitcoin can easily withstand; the second involves state actions or coordinated infrastructure attacks, which pose a serious risk.

How has Bitcoin’s resilience to underwater infrastructure changed over time?

The study shows that the network’s physical resilience does not follow a predictable path. Between 2014 and 2017, Bitcoin experienced its most resilient period, with high geographic diversity and a critical failure threshold of 0.90-0.92.

From 2018 to 2021, the situation rapidly reversed. Despite rapid network growth, geographic concentration increased, sharply reducing resilience. During China’s mining ban in 2021, the threshold dropped to a low of 0.72. When the network was redistributed in 2022, resilience partially recovered to 0.88. By 2025, it remains balanced at around 0.78.

The role of Tor: An unexpected underwater infrastructure benefit for privacy

One of the most interesting findings is how increasing Tor (The Onion Router) usage reduces Bitcoin’s physical fragility. Conventional wisdom suggested that Tor nodes’ obscured locations might make the network more vulnerable. However, Cambridge researchers developed a four-layer model and found the opposite.

By 2025, 64% of Bitcoin nodes use Tor. They observed that Tor relay infrastructure is concentrated in European countries like Germany, France, and the Netherlands, which have extensive submarine cables and land borders. Cutting these connections is extremely difficult. As a result, Tor has contributed between 0.02 and 0.10 to the critical failure threshold, significantly enhancing overall network resilience.

The researchers describe this as “adaptive self-organization.” After censorship events like Iran’s 2019 internet shutdown, Myanmar’s 2021 military coup, and China’s mining ban, the Bitcoin community naturally shifted toward censorship-resistant infrastructure without central coordination. This migration, coincidentally, also makes physical infrastructure more difficult to break.

The Strait of Hormuz and submarine infrastructure threats are no longer theoretical

The current threats to the Strait of Hormuz and regional conflicts that could damage infrastructure have moved the submarine cable failure scenario from theoretical to plausible. Cambridge’s research indicates that, unless specific critical cables and hosting providers are deliberately targeted, Bitcoin is unlikely to experience significant outages.

However, the study also clearly shows how little resources are needed for state-level intervention to cripple the network. While random disasters pose almost no threat, targeted operations could be much less damaging than expected.

How markets have responded to Bitcoin’s underwater infrastructure resilience

Following US President Donald Trump’s announcement of a five-day suspension of Iran energy infrastructure attacks, Bitcoin experienced a strong rebound last week. BTC is currently trading at around $70,630, up 3.91% in 24 hours. Other cryptocurrencies like Ether, Solana, and Dogecoin gained about 5%, and mining stocks related to crypto also followed the upward trend.

Analysts suggest that Bitcoin’s next move depends on whether oil prices and shipping through the Strait of Hormuz stabilize. If tensions ease, the market could retest the $74,000–$76,000 range. Conversely, if tensions worsen, prices could retreat to the mid-$60,000s.

In conclusion, the Cambridge study shows that Bitcoin’s underwater infrastructure is far more robust than it appears, but it faces serious risks from targeted attacks. The future threat landscape is increasingly likely to stem from geopolitical interventions rather than natural events.