Multiple submarine cables in southern France were disrupted overnight, the effects of which made even global Internet access unreliable for a time. Engineers repaired a broken link and the investigation is still ongoing. As the conflict in Ukraine continues, some conspiracy theorists have pointed the finger at Russian submarines, but investigators have yet to find any evidence to support that hypothesis.
A serious accident on Wednesday night on an undersea cable located in the southern waters of France has caused widespread Internet connectivity problems. At least three fiber optic cables were down at 20:30 (UTC), slowing Internet access for users in Europe, Asia and the United States. Cloud computing companies need to adjust backbone paths to maintain reliable connectivity.
According to a report from cloud security firm Zscaler, unexpected cable damage leads to packet loss and increased latency for websites and applications in the affected path. The company identified three broken links. Marseille-Lyon, Marseille-Milan and Marseille-Barcelona. Zscaler routed Internet traffic where possible to mitigate the problem. However, in some cases the action was hampered by applications and content providers still using the severed links.
In a later update posted at 1:03:15 UTC, Zscaler confirmed that workers had repaired one of the affected links and soon observed a drop in packet loss and a reduction in latency for websites and Internet applications. The remaining links (possibly Marseille-Milan and Marseille-Barcelona) were confirmed disconnected by physical fiber tests, and search operations to find damaged points in the submarine fiber optic cable are still underway.
Local and global investigations are underway while Internet connectivity slowly returns to normal. French authorities have gathered evidence about the incident. Meanwhile, unrelated cable damage in the UK has sparked wild speculation that the severed line may have involved unknown saboteurs.
The BBC also reported that an undersea cable linking the Shetland Islands to Scotland was damaged at around the same time as the S.F. fibre optic cable break. The break left the Shetland Islands virtually isolated from the rest of the world. While the Shetland fiber optic cable was severed, technicians were also working to restore another fiber optic cable connecting the Faroe Islands to Shetland that had been cut a week earlier.
Historically, it is highly unlikely that multiple incidents would occur simultaneously on Europe’s submarine fiber optic infrastructure.
