Imagine steering a car at night through a gloomy forest with all the headlights switched off. Surely, it won’t be long before the inevitable happens and you wind up in a ditch. Now, picture yourself switching on the lights just in time to see a tree and swerve out of its path. It sounds like an unrealistic scenario yet it’s remarkably similar to a service provider operating without proactive fiber monitoring. They drive their networks without lighting the fiber with a test signal. Hence, they have no way of identifying degradations or locating fiber damage in real time.

By relying on post-failure trouble management, they put their network and the services they provide at risk. Mission-critical and revenue-generating services can get disrupted, often with significant negative customer impact. Lack of fiber integrity information can also increase operational cost, as service teams waste valuable time on failure analysis and frequently enter dead-end roads as repair attempts turn out to be unsuccessful.

There is a simple way to solve this problem. Proactive fiber monitoring systems evaluate the integrity of a fiber link by coupling an optical test signal into the fiber and analyzing the reflected signal. Yes, this is similar to OTDR test equipment. However, there is a smarter way to design such systems using the latest photonic technology. The ADVA ALM is an advanced link monitoring solution for in-service, proactive fiber monitoring with very different economics compared to legacy OTDR test equipment.

Advanced link monitoring detects fiber degradation, enabling network operators to initiate counter-action even before network performance is affected, resulting in better service quality and higher service revenues. In case of fiber failures, the location of the breakage is immediately identified in real time and expensive failure analysis is avoided. This reduces repair times and maintenance cost.

Dark fiber providers face the challenge of service teams being triggered by many false alarms. It often turns out that the failure is not even with the fiber plant but caused by a pulled connector or a broken network interface. Again, proactive fiber monitoring allows failure isolation before money is wasted with unsuccessful repair attempts.

You might ask why such a valuable assurance tool is not already implemented in all networks. The reason is that there is a wrong perception that fiber breaks can be handled at a higher network layer. As complexity increases with higher network layers, multi-layer management tools are powerful but complex and difficult to operate. Despite the complexity, those multi-layer systems are not able to differentiate between interface defects, fiber breaks, degraded splices or accidentally pulled connectors. The information about a link failure is deeply buried within the complexity of the management tool and it requires considerable skill and training to understand the root cause of a problem. What’s more, access to such management systems is frequently not granted to maintenance teams responsible for the fiber infrastructure.

Today, service providers have a choice. They can now apply a cost-efficient, in-service fiber monitoring system to control fiber integrity and identify link failures at the lowest network layer in full isolation from higher layers. As service providers implement assurance functions at each network layer, they eliminate cost-creating operational doubt about the root cause of a problem. This reduces the negative impact on service quality and helps decrease downtime.

What’s more, independent monitoring systems are easy to implement and simple to operate, making them ideal for the operational requirements of a workforce responsible for maintaining the fiber plant.

Thanks to advanced fiber link monitoring, the whole idea of starting to track down a problem with an OTDR after it has occurred will be a distant memory. Full visibility of any incident or degradation, even before it hits service quality, puts service providers in the driving seat of network operations. As more service providers discover the benefits, it surely can’t be long before they all turn on the headlights and take this route to greater efficiency.