Red Sea cable cuts

Microsoft yesterday announced its Azure cloud platform experienced increased network latency affecting traffic routes through the Middle East. The disruption stems from undersea fiber cuts in the Red Sea that began impacting network performance at 05:45 UTC on September 6.

According to Microsoft's Azure status page, network traffic traversing through the Middle East may experience increased latency due to undersea fiber cuts in the Red Sea. Network traffic is not interrupted as Microsoft has rerouted traffic through alternate network paths. We do expect higher latency on some traffic that previously traversed through the Middle East. Network traffic that does not traverse through the Middle East is not impacted.

The company has committed to providing daily updates or more frequent communications if conditions change, with the last update posted at 22:33 UTC on September 6, 2025.

Strategic chokepoint creates cascading vulnerabilities

The Red Sea represents one of the most critical submarine cable chokepoints in global telecommunications infrastructure. This narrow waterway connects Europe, Asia, and Africa through a concentrated network of fiber optic cables that handle approximately 17% of global internet traffic between these continents.

According to academic research, submarine cables can be considered among the most stable interfaces between continents over the past two centuries, forming physical connection nodes between points separated by sea. However, these cables have also been the subject of both covert and overt disputes between nations in potential conflict or as instruments of war.

The geographical constraints of the Red Sea force multiple cable systems through the same narrow maritime corridor. The mapping of these questions along the Atlantic Ocean axis allows observation, beyond security vulnerabilities, of present assets that support a reliable system of transatlantic relations. This concentration creates a single point of failure scenario where damage to the seabed in specific locations can simultaneously affect multiple cable systems.

Recent geopolitical tensions have heightened concerns about the intentional targeting of submarine cables. Several undersea communications cables in the Red Sea have been cut, affecting 25% of data traffic flowing between Asia and Europe, a telecoms company and a US official say. The February 2024 incident involved damage to four major cables following attacks on commercial shipping in the region.

Why submarine cables matter for global connectivity

There are currently 597 subsea cables in operation or under construction as of April 2025, compared to 559 subsea cables in 2024. These cables account for an estimated 99% of international data traffic, representing critical infrastructure underpinning global telecommunications and financial flows.

The economic importance of these underwater networks cannot be overstated. Notably, the connections established through interoceanic communication cables made possible the first intercontinental intersections and information exchanges without the support of paper compendiums transported by maritime transport. Modern submarine cables carry far more than simple communications - they enable real-time financial trading, cloud computing services, and the digital backbone of international commerce.

In just one day, transactions through this route can involve around 1 trillion dollars. This massive financial flow demonstrates why cable disruptions create immediate economic ripple effects across multiple sectors and geographical regions.

The technical specifications of modern submarine cables make them both remarkably robust and surprisingly vulnerable. In an increasingly global and technological world, the infrastructures that support rapid and permanent digital connectivity become essential as the transmission of the same amount of data by other means is slower, more expensive, and insufficient to meet current needs worldwide.

Geopolitical tensions drive intentional targeting

Recent events have made it clear that subsea cables are at risk. NATO's adversaries are not only aware of the existing vulnerabilities related to this type of infrastructure, but also ready and willing to exploit them. The pattern of cable damage in strategic waterways suggests a shift from accidental damage to potential state-sponsored sabotage.

Geopolitical tensions - namely, Russia's war against Ukraine and China's coercive actions toward Taiwan - very likely remain the primary drivers of state-linked sabotage activity targeting submarine cables. Intelligence assessments indicate that both Russia and China have developed capabilities to target underwater infrastructure as part of hybrid warfare strategies.

The methodology of cable attacks has evolved beyond simple cutting. At least five of these nine incidents were attributed to ships dragging their anchors, including four Russia- or China-linked vessels operating under suspicious circumstances or with opaque ownership structures, although the resulting investigations have highlighted the difficulty of attributing cable cuts to state-sponsored sabotage.

This anchor-dragging technique provides plausible deniability while achieving strategic objectives. Ships can claim mechanical failures or navigational errors while deliberately damaging critical infrastructure. The investigation challenges create legal and diplomatic complications that benefit the attacking party by making attribution difficult.

Technical repair challenges compound disruption impact

Without a significant expansion of dedicated repair vessels, repair capacity is very likely to lag behind demand, pushing median restoration times beyond the current 40-day benchmark. The global submarine cable repair fleet consists of approximately 80 specialized vessels, but most focus on installing new systems rather than emergency repairs.

The repair process involves multiple complex steps that extend timelines significantly. National permitting delays and conflict zone access restrictions will likely extend repair times further, making streamlined diplomatic clearance processes an increasingly critical element of submarine cable resilience.

Repair vessels must obtain permission from multiple jurisdictions along cable routes. In conflict zones like the Red Sea, security considerations create additional delays. Last month, Yemen's internationally-recognised government warned that the Iran-backed Houthi movement might sabotage the undersea cables in addition to attacking ships in the sea. The Houthis - who control much of western Yemen's Red Sea coast - denied last week that they had targeted cables and blamed US and British military strikes for any damage to them.

The technical complexity of underwater repairs means that even minor damage can require extensive intervention. According to the ICPC, cable repairs average between $1 and $3 million, require "specialized cable ships with highly trained crews," and can take months to complete.

Regional dependencies create an unequal impact

The concentration of cables through specific geographic chokepoints creates unequal vulnerability distributions across different regions. Regions with low redundancy, such as parts of West and Central Africa, isolated Pacific islands, and certain secondary European routes, are more likely to suffer disproportionate impact from cable damage, especially when geopolitical tensions coincide with infrastructure constraints.

The Red Sea incident particularly affects Middle East connectivity because alternative routing options require significantly longer paths. For example, the Red Sea cable cuts in February 2024, detailed above, illustrated the importance of route diversity. The March 2024 damages to four cables off West Africa, which all occurred due to an underwater landslide in the "Le Trou Sans Fond" canyon off of Côte d'Ivoire, illustrated how a concentration of cables at one point can make multiple cables susceptible to human-made threats or, as in this case, natural phenomena.

Traffic rerouting through alternative paths creates cascading effects on global network performance. When Red Sea cables fail, traffic must route through terrestrial networks across Russia or longer submarine paths around Africa. Both alternatives introduce significant latency penalties and capacity constraints.

Digital marketing implications and business continuity

The submarine cable disruptions create immediate challenges for digital marketing operations that depend on real-time connectivity between regions. Government-directed shutdowns particularly impact programmatic advertising and real-time bidding systems that depend on consistent network connectivity.

Programmatic advertising platforms require millisecond-level response times for real-time bidding auctions. Increased latency can prevent participation in advertising auctions or reduce bid competitiveness. The financial impact extends beyond individual campaigns to affect entire advertising ecosystems.

PPC Land has extensively covered how Internet traffic patterns affect marketing operations, noting that global traffic grew 17% in 2024 despite recurring disruption challenges. The platform has highlighted how government shutdowns now account for over half of major Internet disruptions globally.

Content delivery networks face particular challenges during cable disruptions. Geographic content caching strategies must adapt to altered traffic patterns, potentially requiring emergency replication to alternative data centers. Video streaming services, which consume substantial bandwidth, often implement quality reduction protocols during network congestion periods.

Strategic implications for NATO and allied nations

This inevitably gives rise to numerous implications for the security and interests of allied States. The attacks on submarine infrastructure represent a form of hybrid warfare that operates below the threshold of conventional military response. NATO nations patrol Baltic Sea as cables fail demonstrates how alliance members must adapt naval operations to protect critical infrastructure.

In January 2023, NATO and the EU created a joint working group to protect these critical infrastructures. Months later, NATO also created a Critical Undersea Infrastructure Coordination Cell. These institutional responses acknowledge that submarine cable protection requires coordinated international effort rather than individual national responses.

The economic warfare implications extend beyond immediate connectivity issues. While submarine cables, mostly, remain the property of single agents, with few of them still consortiums of more than one entity. This private ownership structure complicates government response options and creates potential leverage points for hostile actors.

China's expanding influence in submarine cable networks

The People's Republic of China, with the growing global relevance of Chinese state companies, such as HMN Technologies, the main manufacturer of submarine cable systems, and state telecommunications operators, such as China Mobile and China Telecom, constitutes a threat to the digital integrity of information circulating in submarine cables. Changes in network routing patterns would have a direct effect on traffic, and the monopoly of international businesses related to manufacturing, installation and repair of submarine cables, can generate technological dependence between countries that interconnect cable systems.

Chinese companies now control significant portions of the global submarine cable manufacturing and installation market. This positioning creates potential security vulnerabilities because infrastructure installation provides opportunities for surveillance equipment placement or system manipulation.

Beijing using cable projects as leverage in naval disputes demonstrates how China leverages infrastructure investments to advance territorial claims. In the South China Sea, cable installation projects become tools for asserting sovereignty over disputed waters.

The technological dependence created by Chinese dominance in cable manufacturing presents long-term strategic challenges for Western nations. Alternative suppliers exist but lack the scale and cost competitiveness of Chinese manufacturers.

Russian submarine capabilities and cable targeting

The Russian Federation represents a more conventional type of threat to the physical integrity of submarine cable systems. Its extensive rearmament program, focused on increasing its naval and underwater capabilities, resulted in the creation of the world's largest fleet of deep-sea vessels.

Russian submarine operations near critical cable infrastructure have increased significantly since 2022. This fleet of submarines and surface ships equipped with manned and unmanned submersibles allows Russia to manipulate objects at great depths, intercept communications and destroy submerged infrastructure.

The dual-use nature of Russian "research" vessels provides cover for intelligence operations. Ships conducting legitimate scientific research can simultaneously map cable locations and test interception capabilities. This intelligence gathering enables future targeting operations if conflicts escalate.

It is known, therefore, that both Russia and China have the naval means necessary to carry out attacks against submarine cable systems in deep waters: submarines, manned and unmanned submersible vessels, and surface vessels with cartographic capability and great depth range.

Economic impact and repair capacity constraints

Unless significant investments are made in streamlining repair processes and expanding cable ship repair capacity, repair times are likely to continue trending upward. According to SubTel Forum, the average repair time for the restoration of cable faults has risen from 2015 to 2024, with the average repair time in 2023 consisting of 40 days.

The economic implications of extended repair times compound during major incidents. In March 2024, an underwater rock slide damaged four submarine cables off West Africa: the West African Cable System (WACS), Africa Coast to Europe (ACE), MainOne, and SAT-3 cables. NetBlocks reported disruptions to internet connections in at least sixteen Central and West African countries, with disruptions to mobile payments and cloud applications for several days.

The outage also left multiple Nigerian banks offline, severely impacted connectivity in Ghana, and incurred estimated repair costs of $8 million. These financial impacts demonstrate how submarine cable damage creates cascading economic effects far beyond telecommunications costs.

The limited global repair capacity means that multiple simultaneous incidents could overwhelm response capabilities. For example, the Léon Thévenin, a cable repair ship docked in Cape Town, South Africa, was the only vessel dedicated to serving Africa at the time of the March 2024 cable outages, extending the repair timeline.

Intelligence gathering and surveillance implications

Beyond simple sabotage, submarine cable networks present opportunities for intelligence gathering that concern security agencies. Beyond these operational means, both countries possess scientific and technological means that allow the placement of sensors on submarine cables, which combined with mapping submarine cable routes and studying the behavior of submerged objects, could, in the long term, inform, in an unprecedented way, military activity, compromising the capacity of Allied vessels, manned and unmanned, to circulate undetectably.

Cable tapping operations require sophisticated technical capabilities but provide access to vast amounts of international communications. The legal complexities of underwater surveillance in international waters create additional challenges for preventing such operations.

The strategic value of submarine cable intelligence extends beyond immediate military applications. Economic intelligence, diplomatic communications, and technological transfer monitoring all flow through these underwater networks.

Future resilience and mitigation strategies

Joint public-private partnerships promoting investment in cable repair and maintenance capabilities, enhancing security and surveillance of critical submarine infrastructure, and improving resilience in current and future cable networks will be critical to addressing rising threats to cable infrastructure.

Diversification of cable routes represents one approach to reducing chokepoint vulnerabilities. However, geographical constraints limit alternative routing options through certain regions. The Red Sea remains unavoidable for direct Europe-Asia connectivity despite security concerns.

Timeline

2024-2025 Red Sea incidents

• February 2024: Multiple cables (AAE-1, EIG, SEACOM) damaged in Red Sea following Houthi attacks on commercial shipping, affecting 25% of Asia-Europe traffic
• March 4, 2025: PEACE cable severed at 1450km from Zafarana in Sudan EEZ, affecting Pakistan-Europe connectivity with repairs estimated for mid-April 2025
• September 6, 2025: Current incident causing Microsoft Azure latency issues beginning at 05:45 UTC, ongoing with daily updates

Related global infrastructure disruptions

• Internet outages reach 'shutdown season' across 125 countries in Q2 2025 - Government-directed shutdowns affected digital infrastructure across multiple regions, creating challenges for programmatic advertising
• Internet traffic surges 17% in 2024 as global digital transformation accelerates - Analysis of growing dependency on digital connectivity amid infrastructure challenges and security threats
• Global internet traffic soars - Previous year's trends showing over 180 global internet outages, many from government-imposed shutdowns

Summary

Who: Microsoft Azure cloud platform customers and global internet users dependent on Middle East routing infrastructure, with broader implications for NATO allies and submarine cable operators

What: Increased network latency affecting Azure services due to undersea fiber cuts in the Red Sea, representing part of a broader pattern of submarine cable vulnerabilities exploited through geopolitical tensions

When: Beginning at 05:45 UTC on September 6, 2025, with ongoing impact and daily monitoring updates, occurring within a context of escalating infrastructure attacks since 2022

Where: Red Sea submarine cable routes connecting Europe, Asia, and Africa through strategic maritime chokepoint, highlighting concentrated vulnerability in critical global telecommunications infrastructure

Why: Undersea fiber optic cables suffered cuts in a region experiencing heightened geopolitical tensions, forcing traffic rerouting through alternate paths with inherent latency penalties, demonstrating how hybrid warfare tactics target critical infrastructure below conventional military response thresholds