Skip to main content

The Achilles Heel of Fiber Optic Networks

By Don Allard, AFL, Test and Inspection Commercial Manager


heel


Society is increasingly reliant on fiber optic networks which serve as the backbone of the modern world. They connect data centers, cell towers and more carrying critical business information, phone calls, text messages, Internet traffic and all-consuming social media. Technological innovations continually improve the quality of fiber optic networks while easing building and testing. Yet one nemesis remains to trouble technicians.

What troublesome nemesis has technology not eliminated? Dirt, oils and other contaminants. How can this be? Simple, single-mode fiber transmits signals over an optical glass fiber with a nominal core diameter of nine microns. For a perspective, human hairs typically range from 75 to 100 microns in diameter. A micron is one-millionth of a meter. If you were able to lay nine micron single-mode fiber cores side by side, it would take 111,111 cores to span a meter.

Dust and dirt particles are, in comparison, quite large. There is also an abundant supply of dust and dirt in this world. This is why contamination continues to plague fiber optic technicians. Network connection points use specialized connectors. When connected, they are closed and sealed. No problem.

connector end-face

The problem arises at initial build time. No matter how clean an environment fiber optic connectors were manufactured in, installation occurs in the field, which can be up a utility pole, down in a manhole, in a basement or a variety of other common (unclean) places. The technician must remove protective packaging and expose the pristine connector end-face to open air in order to connect it to the adjoining connector. This can be enough to attract dirt particles which will block the optical signal (light) from passing through the connector junction, the same as a dirty windshield blocks visibility from the driver’s seat.

Network maintenance also provides an opportunity for contamination of connectors. Any time connectors are disconnected and then reconnected, dust and dirt can migrate to the core area of the connector end-face. This simple action of disconnecting and reconnecting a fiber can “break” a network by introducing enough attenuation to drop the signal level at the far end below the receiver’s acceptable level.

Fortunately, good tools exist for technicians to clean and inspect fiber optic connectors. New cleaners like the One-Click® Cleaner operate by simply pushing the cleaning nozzle against the fiber until the cleaner makes an audible “click.” It’s a quick and simple tool designed to help technicians quickly remove contamination with minimal effort or technique.

one-click cleaner

Due to the small physical size of the fiber optic core, verifying connector integrity is performed via microscope. Technological innovation replaced manually operated scopes with new wiz-bang fast scopes like AFL’s FOCIS Flex inspection tool which automatically focuses on the end-face, centers the image and performs a “Pass/Fail” analysis of end-face integrity, then uploads the image and test results via Bluetooth® to your phone or other device. Like the One-Click Cleaner, FOCIS Flex is fast and simple to operate.

flexscan and focis flex

Fast and simple is key. Most people don’t like to take time to clean, especially when working on a tight schedule. Fiber optic technicians are no different. However, proper network hygiene is a critical part of building and maintaining reliable networks. Taking the time upfront to clean and inspect fiber optic connectors prior to connecting minimizes troubleshooting time and hassle.

Next time you send a text message, check your email, stream a movie, etc. remember that the information traveled at least part of its journey over a glass fiber smaller than one of your hairs. Hopefully, the connectors were properly cleaned!