Remote fiber monitoring has emerged as a popular tool for telecom and data center operators to accurately locate physical fiber issues from a distance and tighten resolution times
Fiber optic cables are often described as the live blood of modern connectivity. Stretching across miles of perilous landscapes and turbulent ocean floors, these trans-oceanic systems carry lightspeed internet and telephony around the world. But in a world of wireless connectivity, they are easy to forget. Until connectivity breaks.
Late in December, a cargo ship en route to Israel was seized by authorities in the Gulf of Finland. The ship had damaged a sub-sea cable, slicing it into half as it passed over it.
Incidents like this are in fact quite common. Maritime records are full of big vessels inadvertently breaking fiber-optic cables while voyaging across the sea.
Typically, when a fiber optic cable breaks — whether that’s on land or in sea — the incident is categorized as — accidental, like in the case above, malicious if there’s evidence of tampering, or random, if the cause is a natural incident like fire, earthquake, or just animals.
What is remote fiber monitoring?
Engineers are now using what is called remote fiber monitoring to check fiber health from afar.
Fiber optic cables are not the typical set and forget installations. Whether buried underground or submerged in water, they need to be probed and checked by field crews to ensure health and integrity.
When an underwater line gets sliced by a stranded vessel, or sabotaged by bad actors, everything from the nearby hospitals to houses lose connectivity, which gives engineers a very slim response window to work with.
With traditional methods of inspection relying on on-site technicians, the OPEX is high, and repair times even higher. Remote fiber monitoring allows engineers to keep a finger on the pulse from a distance. The systems perform continuous tests providing full field accuracy remotely — no expensive truck rolls, no time-intensive reworks.
How does it work?
Remote monitoring systems offered by different test and measurement vendors all work slightly differently. The best ones include what is called OTDR or Optical Time-Domain Reflectometer, a widely-used testing device for characterization, certification, and troubleshooting of fiber optics. In this case, the OTDR sends out light pulses through cables and analyzes the feedback for light loss and attenuation. The signal reflections tell whether it’s a full cable cut or partial impairment — and at what distance.
A key feature of remote fiber monitoring systems is continuous testing. The systems are designed to automatically trigger OTDR tests at set cadences via their cloud-based management applications. This allows network operators to continuously collect and analyze metrics, like link loss, link continuity, link quality, and so on.
The feeds are collected, stored, and crunched by algorithms to calculate the attenuation levels, before being sent downstream to a dashboard that serves as the online repository for all test records. When a reading deviates from the baseline performance, engineers are alerted via their preferred channels (email, text, IM, etc.).
The management layer offers engineers capabilities to configure the tests for different fiber types (dark vs lit, point-to-point vs passive optical network fibers), tune the OTDR performance parameters, adjust system sensitivity, and set up alerts and notification systems matching their monitoring needs.
Many new systems also include mapping tools that collect geolocation data to provide full visual representations of the monitored network for the benefit of field technicians.
Depending on the provider, a remote monitoring solution can be a mix of separate test hardware systems and the management software, or an all-in-one platform that orchestrates the entire process with a push of a button.
