At Submarine Networks Europe 2018, London, February.  I hosted a round table discussion on protecting our subsea cable infrastructure. After over 150 years of relative obscurity the importance of subsea telecommunications cable infrastructure is now dawning across the globe. In a little over 25 years the internet and modern communication technology have transformed the planet. The way we communicate, interact socially, consume visual/ audio entertainment, share knowledge, conduct business, pretty much every facet of modern life is now either dependent or enhanced by the internet and the infrastructure that underpins it.

Such dependency has caused governments to ask pertinent questions. i.e. “what would happen if our subsea links were attacked and cut?” and “what could we do protect our subsea links and mitigate potential risks to their security?”  When you consider a recent report from Huddersfield University estimated that subsea cable infrastructure enabled £65billion of value to the UK, you can see they are right to explore answers to these questions.

The oldest, and still the best way, to maintain subsea connectivity is to build resilience into the network. Redundancy of capacity through multiple cable systems combined with diversity of cables systems through geographical separation.

It is an unfortunate fact that cables are at threat of damage every day. In Northern European waters there are on average 30-40 cable damages every year caused by interaction with commercial fishing fleets and errant ship’s anchors. The impacts of these outages are largely imperceptible to users due to the resilience provided by the Network.

There is also a global fleet of cable repair ships on standby for when a cable under their jurisdiction is damaged.  From damage notification to repair can be as little as 7-10 days, in Northern European waters.

The network can accommodate multiple damages and they can be repaired quickly but how can we prevent damages?  As the overwhelming risks come from commercial fishing and anchors that is where cable owners should, and do, focus.

  • Fishing liaison projects,  such KIS-ORCA .
  • Improvements and increased use of AIS monitoring services.
  • Threat of legal action and repair costs against vessels that damage cables.
  • Reporting of anchor strikes to marine accident authorities.

When discussing cable protection, the subject of Cable Protection Zones is always raised. Some countries do employ CPZ’s and they can work when designated and managed correctly. However, they are not applicable for every country and their use needs to be gauged carefully. The enforced use of CPZ’s could limit the freedoms enjoyed under UNCLOS to freely lay cables. CPZ’s would essentially funnel cables into one corridor removing the element of diversity away from submarine route planning potentially making cables “more” vulnerable to a ship’s anchor/fishing trawler, not less. They would also limit the landing locations available to operators.

Most of the legal regimes governing protection/damage of subsea cables is still based on the 1884 Convention of Submarine Telegraph Cables, and although the articles contained within are still very relevant it may be time to have a another look. 

Unfortunately in recent months the debate on protection/damage of subsea cables has been somewhat hijacked by sensationalist articles on the perceived threat of a co-ordinated attack from a rogue nation.

The catalyst for the recent media coverage was a recent report for the UK Think Tank “Policy Exchange” by Rishi Sunak, a member of the UK Parliament. Unfortunately this report was produced without any consultation with the subsea cable industry and as such some of the recommendations suggested within it are best described as – questionable.

Physical security of the internet is the same as with any large network, it is only as secure as its weakest point.  Subsea cables are by their very physical condition usually difficult to access. Malicious intent against subsea cables is historically very rare. (Instances in the past such as the UK cutting German telegraph cables in WW1 and speculation, never corroborated, about cable sabotage in waters near Alexandria, Egypt in 2008 are only two that come to mind and there aren’t many more) Any telecoms network can usually be accessed either by lifting the cover of a footway chamber or via a pole/pylon. A lot cheaper and easier than going to sea. 


Although the internet is awash with articles about threats to subsea cables; attacks from rogue nations, being eaten by sharks and being tapped by submarines. The reality is much more mundane.  The main threat to subsea cables remains commercial fishing and ship’s anchors and the best way to maintain connectivity is redundancy of capacity through multiple cable systems combined with diversity of cables systems through geographical separation.

Peter Jamieson IEng MIET, MSCTE, MCMI

Principal Engineer – Core Fibre & Subsea Networks.  Liberty Global  

Vice-Chair: European Subsea Cable Association


Peter Jamieson was a speaker at Submarine Networks Europe 2018 in London. The event, organised by Total Telecom, will be back in 2019, find out more at