Beneath the oceans lies over 1.4 million kilometers of fiber-optic cable—enough to circle the Earth more than 35 times—forming the infrastructure that powers today’s digital economy. These cables connect over 400 international landing stations and enable core services such as cloud computing, video conferencing, financial trading, and global data center operations.
According to TeleGeography, over USD 10 billion was committed to new subsea cable systems globally between 2022 and 2024. These include major hyperscalers like Google, Meta, and Microsoft, which are now investing directly in subsea networks to support their expanding cloud footprints.
But what happens when a cable fails? Whether due to earthquakes, fishing activity, anchor drag, or sabotage, outages can cause crippling slowdowns, regional internet blackouts, and costly interruptions to global business operations. As latency-sensitive industries like fintech and artificial intelligence (AI) scale further, undersea cable failures are proving to be a risk that require proactive resilience planning.
Also Read: Subsea Data Centers: Will the Future of Cloud Computing Sink or Swim?
Real-World Disruptions: Learning from the Biggest Failures
In recent years, several major undersea cable outages have exposed the vulnerabilities of global internet infrastructure and the severe consequences such failures pose to businesses. Between 2020 and 2025, both natural and human-made incidents have led to widespread connectivity issues, highlighting just how dependent the global economy has become on these invisible lifelines.
The largest subsea cable outage in recent history occurred in March 2024, when multiple major cables in the Red Sea region were severed, disrupting approximately 25% of internet traffic between Asia, Europe, and the Middle East. Specifically, four major cables—AAE‑1, EIG, SEACOM, and TGN—were damaged, creating widespread service degradation across East Africa, South Asia, and Europe.
Why this incident stands out:
- Scope of impact: A quarter of regional traffic affected across continents.
- Country-level severity: Deep connectivity outages in Ethiopia (up to 90%) and Somalia (around 85%).
- Cascading service failures: Disruptions affected cloud services, financial systems, and business operations across multiple regions.
While no country experienced complete isolation, service quality dropped significantly in regions such as India, Pakistan, and parts of East Africa. Online platforms slowed considerably, and critical industries were forced to reroute traffic through alternative subsea routes, often at reduced capacity. Efforts to restore connectivity were hampered by geopolitical tensions and complex logistics in the Red Sea area.
It is worth bearing in mind that unplanned downtime costs businesses an average of USD 5,600 per minute, according to Gartner. In the case of the Red Sea cable disruptions, the total estimated economic impact reached USD 3.5 billion, underscoring the scale and severity of such outages on global operations.
A notable large-scale disruption occurred after the Hunga‑Tonga‑Hunga‑Ha‘apai volcanic eruption in early 2022, which severed the island nation’s only connectivity via undersea cable. Connectivity was cut off for over a month, crippling all internet-based commerce, communication, and emergency coordination until repairs were completed roughly 38 days later.
Meanwhile, the Baltic Sea region experienced at least 11 subsea cable disruptions between 2023 and 2025, some of which took weeks to repair. These outages caused widespread interruptions to cross-border data flows and cloud services, with financial losses in 2023 estimated at EUR 20 to 30 million.
Additionally, in June 2024, Vietnam faced significant connectivity challenges, with three of its five subsea cables simultaneously out of service, disrupting internet performance across the country. In response, authorities announced plans to invest in up to four new international cable systems, aiming to boost capacity by 60 Tbps by 2025 to enhance resilience.
During Q1 of this year, the Pakistan and East Africa Connecting Europe (PEACE) submarine cable was also cut in the Red Sea, causing widespread internet disruptions across the region.
These disruptions drive home the crucial lesson that subsea cable outages are not just technical failures but business-critical events with global financial consequences.
Also Read: World Oceans Day 2025: Why Our Digital Future Depends on the Deep
The Domino Effect: Why Outages Are a B2B Crisis
Undersea cables are far more than mere infrastructure; they serve as vital arteries that connect cloud providers, software-as-a-service (SaaS) platforms, and multinational corporations within the business-to-business (B2B) ecosystem. Tech leaders like AWS, Microsoft Azure, and Google Cloud depend on these submarine networks to maintain high-performance links between data centers across continents.
A disruption to a key route can degrade cloud performance across continents, impacting data exchange, application programming interface (API) access, and service reliability. In October 2023, when the SEA‑ME‑WE‑5 cable went offline for repairs, Kentik observed latency spikes of around 40 ms between Europe and Asia across all major clouds, signaling how critical cable integrity is to enterprise-grade services.
Even short-lived latency deviations can trigger outages in latency-sensitive sectors. In fintech and high-frequency trading, milliseconds matter; delays can lead to missed arbitrage opportunities, failed trades, or system errors. In healthcare, telemedicine platforms and remote diagnostics may endure timeouts or degraded image transfers. In manufacturing, industrial IoT (IIoT) systems and supply-chain integrations risk desynchronization, potentially halting automated production lines.
Beyond service interruptions, longer outages carry regulatory and reputational consequences. As per past reports, London and New York financial centers carry cumulative daily transaction volumes worth USD 10 trillion, which pass through undersea cables. A simultaneous cable failure could destabilize markets; yet, few regulators currently subject such scenarios to formal stress testing. With this in mind, extended B2B disruptions raise concerns about compliance with financial resilience rules and network uptime mandates. Companies may face fines, liability claims, and damage to brand trust for failing to maintain high service continuity.
Companies that neglect to monitor or mitigate undersea cable vulnerabilities place not just operations but also reputation, compliance, and global partnerships on the line.
Recent: Tech CEOs Face Questions Over Submarine Cable Security
Business Continuity Planning: Is Your DR Plan Subsea-Proof?
As the global economy grows increasingly digital and distributed, business continuity planning must evolve beyond traditional backup models. For enterprises and cloud providers, preparing for undersea cable disruptions has become a mission-critical priority. So how do leading organizations build disaster recovery (DR) plans that account for subsea vulnerabilities?
1. Geographical Redundancy and Cable Diversity
Modern DR strategies emphasize path diversity, utilizing multiple submarine cable systems that land at different geographical locations. This approach ensures that if one cable route is disrupted, data traffic can be quickly and efficiently redirected through alternative pathways, minimizing downtime and service disruption.
2. Edge Computing and Content Caching
Deploying compute and storage closer to users minimizes the dependency on long-haul international traffic. Edge infrastructure and content delivery networks (CDNs) can deliver low-latency services, even when core subsea connections are compromised.
3. Cloud-Based Failover Systems
A cloud-native architecture enables automatic failover of services to different regions or cloud providers. For example, AWS and Azure offer cross-region replication and routing services to shift workloads in real time.
4. Traffic Rerouting and Peering Strategies
Working with Tier-1 internet service providers (ISPs) and internet exchange points (IXPs) allows for dynamic routing policies. Smart peering and border gateway protocol (BGP) optimization can mitigate the impact of latency or packet loss during outages.
5. Vendor and Infrastructure Audits
Enterprises should regularly audit their connectivity providers. Critical questions include:
- How many cables support your region?
- What is the mean time to repair (MTTR)?
- Is there an active monitoring and alerting system for disruptions?
- Are your services backed by service-level agreements (SLAs) that account for subsea outages?
By embedding these strategies into continuity plans, companies can withstand disruptions and maintain service reliability, even when the world’s digital pathways are compromised.
