Telecoms FAQs

Telecoms FAQs

Telecoms Cable Monitoring: Your Questions Answered…

Using DFOS (Distributed Fibre Optic Sensing) to monitor your fibre optic telecoms cable networks is a smart decision. It delivers real-time, value-adding intelligence on any disturbance – even in remote or subsea locations. Here are some of the common questions Fotech receives about DFOS telecoms monitoring and our LiveDETECT modular monitoring solution. If you can’t find the answer to your question here, please contact the Fotech team and we’ll be delighted to help!

You can also visit our:


Fotech Resources Section


Telecoms Cable Monitoring Section


Technology Section

Perimeter Security

Telecoms FAQs in Full

Damage to telecoms cables can have very serious consequences in a world where we depend on connectivity. Damage is most commonly caused by:

  • Co-located events such as onshore building or excavation works, or subsea events including natural environmental changes, anchor drag or cable strikes.
  • Illegal interference, theft, or malicious damage to onshore cables.
  • Telecoms cable exposure (subsea or onshore) due to loss of burial.
  • Breakdown or wear and tear to the cable insulation (cable arcing).
  • Cable integrity problems that can easily be missed by ROV (remote operated vehicle) passes or bathometric inspections

The telecoms industry is worth a staggering $1.54 trillion worldwide. In a world where customers demand always-on connectivity, damage to a fibre optic telecoms network can be disastrous for revenue, reputation and productivity. If left undetected, accidental or malicious onshore and subsea cable damage is difficult, expensive and potentially dangerous to repair. A system that alerts immediately and accurately on the nature and location of the problem is not just an operational extra. It is a business-critical necessity to protect against telecoms outages that can disrupt major global services. DFOS (distributed fibre optic sensing technology) is an advanced, robust, always-on solution for monitoring any telecoms cable, anywhere in the world, no matter what the location or length of the asset.

Unlike other telecoms monitoring techniques, such as periodic manual, ROV or bathometric inspection, LiveDETECT II® monitors the fibre optic cable automatically, twenty-four hour a day, every day. The vast quantities of data that LiveDETECT with Helios® and Panoptes generate provide enhanced intelligence on the location of the threat to within metres. Not only that, but every disturbance is also assigned a unique vibrational signature, generating accurate data as to the likely cause of the telecoms cable interference. LiveDETECT II® ensures that, when a threat to your telecoms cable network occurs, you are immediately alerted as to the location, nature and risk level of the threat. Your people can then decide on a targeted, fast and safe response to fix the problem before it becomes serious.


Modern distributed fibre optic sensing (DFOS) technology can detect any disturbance along a fibre optic telecoms cable within just minutes. DFOS works by sending thousands of pulses of light every second along the cable, some of which is returned in a process called Rayleigh Backscatter. If an event happens that disturbs the telecoms cable – whether onshore or offshore, DFOS detects the corresponding disturbance to the backscatter. Fotech’s LiveDETECT II® DFOS telecoms monitoring uses machine learning and AI to analyse every disturbance and transmit that intelligence to you. It can tell you the location of the event within metres, as well as the likely cause of the event. Not only that, LiveDETECT II® filters out any false or benign disturbances and, when the disturbance is genuine, issues an instant warning with a risk level. This gives you the accurate insights you need to ensure that your response is as rapid, targeted, cost-effective and safe as it can possibly be.

For telecoms operators, their cable networks are hugely valuable and already generate trillions of dollars of revenue. But there is more potential out there, thanks to advanced distributed acoustic sensing (DAS) technology. Fibre optic cables are typically co-located with other assets, including pipelines and security perimeters. They are also integral to modern smart city management.

Installing DFOS technology along your fibre optic cable, therefore, creates a new business proposition. The data generated by DFOS along your proprietary fibre optic cable also offers an invaluable opportunity for other companies seeking to protect co-located assets. Pipeline operators, for example, attach enormous value to automated pipeline monitoring to prevent unnecessarily difficult and expensive repairs in remote locations. Road and rail operators prize the data DFOS can generate from fibre optic sensing, since it gives valuable insights for rail and road monitoring and management as well as other smart city applications.

As the owner of the fibre optic cable, Fotech’s LiveDETECT II® can generate a new revenue stream amongst customers keen to access the data that your telecoms cable is generating to safeguard their own assets.

Absolutely, but you need the right technology calibrated in the correct way. Fotech’s modular DFOS telecoms monitoring system, LiveDETECT II®, works 24 hours a day to monitor the entire length of the fibre optic asset, detecting threats in a matter of minutes. Whilst DFOS provides the vibrational sensing, Fotech’s specially developed Helios® interrogator and Panoptes modules provide the machine learning that monitors and interprets data and alerts the telecoms operator instantly. When LiveDETECT II® is installed and configured on your telecoms cable, you are equipped to know about any disturbance and the likely cause within minutes, so that you can take fast, decisive action.

DFOS stands for distributed fibre optic sensing. It can be installed on any fibre optic cable – either during initial cable laying or retrospectively. The DFOS unit fires thousands of pulses of light along the cable every second, and backscatter light is returned the DFOS unit.

If a disturbance occurs on or around the telecoms cable, the corresponding anomalies in the backscatter pattern are immediately detected. Fotech’s Helios® interrogator uses pioneering photonics, artificial intelligence and machine learning to perform incredibly sophisticated analyses of each vibrational disturbance, filtering out any false or irrelevant alarms and interpreting the likely cause of the disturbance. This information is transmitted to the Panoptes® server within minutes. Panoptes then alerts you as to the threat and the severity of the threat within just seconds.

Fotech has field tested the Live DETECT II® detection system in live onshore, subsea and remote environments. The tests returned 100% accurate results with no false positives.

Yes. Flashover testing is commonly used to perform manual diagnostic tests on fibre optic cables and co-located cabling. The process can easily cause further damage to the integrity of a fibre optic or co-located cable.

By harnessing DFOS (Distributed Fibre Optic Sensing) technology to automatically monitor fibre optic cable disturbances, repair teams are better equipped to pinpoint both the location and the nature of the disturbance or damage. As well as optimising the repair strategy, this intelligence can greatly reduce the need for multiple flashover tests and therefore reduce the risk of further harming valuable fibre optic networks.

LiveDETECT® II is a modular system that can be fully calibrated, so it can be expanded to monitor the entire length of your fibre optic telecoms cable, whether you are operating a single linear asset or an entire telecoms cable network. This is the case in both onshore and subsea telecoms cable environments.

Yes, LiveDETECT II® can be used to monitor telecoms cables in any location – from smart city centres to remote and hostile onshore terrains, or deep subsea terrains. Of course, being able to monitor the safety and integrity of your telecoms networks remotely has significant commercial and operational advantages. It can greatly reduce – and sometimes eliminate – the cost, time and risk associated with deploying repair teams. It can also detect and immediately warn you of threats to your fibre optics that can easily be missed by traditional monitoring methods.

Because LiveDETECT® II is a highly advanced, modular technology, we build and calibrate every solution to exactly meet the requirements of the individual customer. If you would like to find out more or discuss your requirements, just contact Fotech.

More on Telecoms Monitoring
More on Telecoms Monitoring
Monitoring Subsea Telecoms Cables in a Connectivity Hungry World

Monitoring Subsea Telecoms Cables in a Connectivity Hungry World

Safeguarding telecoms cables against downtime and disaster is a difficult business – but evolving DAS technology plays an important role, as our blog explains.

Solving the Data Dilemma

Solving the Data Dilemma

How Smart Cities Benefit from Fibre Optic Technology

Data, and the sensors and technology used to collect it is central to smart city development. It gives decision-makers valuable insights to efficiently manage assets, resources and services.



Reimagining Full Fibre Roll Outs

Reimagining Full Fibre Roll Outs

Fibre optic cables are no longer limited to internet connectivity. They can also be used in the transition to smart cities.

Finding Subsea Cable Faults Quicker with DAS

Finding Subsea Cable Faults Quicker with DAS

During the pandemic, some countries experienced internet outages due to subsea cable faults. Find out how DAS technology can help detect and pinpoint anomalies faster.

Why Fibre Optic Networks can Form the Backbone of Smart City Projects

Why Fibre Optic Networks can Form the Backbone of Smart City Projects

Fibre optic networks already exist as part of a city's infrastructure, so how can they be used smart-city projects?

This website uses cookies. Click here to learn more. That's Fine