Fiber Monitoring System for WDM/OTN Network: Automatic Monitoring and Troubleshooting

Optical fiber serves as the essential physical infrastructure for modern high-capacity communication networks. It carries critical data and connects thousands of residents, enterprises and other industries. Correspondingly, it would have a considerable impact once there is a broken fiber. Thus, how to identify and pinpoint the problems is urgent.

With the ongoing deployment of Optical Transport Networks in long-distance transmission, fiber monitoring is a well-established strategy to mitigate risks and safeguard assets.

Why Need Fiber Monitoring?

Fibers are vulnerable. They spread all over the planet, and people have tried to protect them as much as possible by upgrading the outer sheath and exploring methods of fiber cable laying. However, animals, construction work, natural disasters, extreme weather, and fiber aging are threats to fiber optics.

In long-haul transmissions and connections among buildings, campuses or cities, fiber damage can lead to costly disruptions in data flow. Locating and restoring these issues may take several hours, days, or even weeks.

To guarantee transmission quality, the maintenance of network infrastructure is important. With automatic fiber monitoring, fault localization, and dispatching in a fiber monitoring system, the efficiency is considerably improved. On the one hand, the system can monitor the operational status of the network, detecting degradation trends ahead of time to prevent potential issues. On the other hand, when fiber breaks happen, rapid response and accurate localization can shorten the duration of disruptions. Extensive data related to construction, splicing, and maintenance activities can be recorded, processed, and queried in the system, which can reduce fiber faults, improve efficiency and alleviate the workload of personnel.

Figure 1: Cable Testing

Understanding of FMT Series Fiber Monitoring System

On account of the urgency of cable monitoring, FS recommends the FMT Series Fiber Monitoring Solution. This solution monitors the WDM/OTN System, helps facilitate non-disruptive fiber optic network monitoring, and provides real-time network diagnostics.

Figure 2: The Topology of FS Fiber Monitoring Solution

Working Principle

The Fiber Optic Monitoring System supports service providers to oversee and diagnose issues in WDM/OTN networks from a centralized location. It applies Optical-time-domain-reflectometer (OTDR) technology to test the fibers and locate the breaks. The system automatically switches to different links with Optical Switches and monitors the optical signals.

Taking the point-to-point network topology as an illustration, initial optical signals from Site A are divided by a PLC, with around 1% transmitted to the OPD for optical power monitoring. The remaining signal passes through the FWDM to reach Site B. Regularly, the OTDR conducts tests to ensure link functionality. The OPD reports power data to the online system, which generates alerts for any irregular signals. In case of anomalies, the OTDR is activated again to pinpoint the fault location. Relevant personnel are informed through SMS, phone calls, emails, or other means.

Key Components

As the brief introduction above, the solution comprises a suite of products, including OTDR, OSW, OPD, FWDM Filter.

Figure 3: The Products List

• Optical Power Detection: The OPD carries on high-precision optical power detection. It supports 4/8/16 channels at 1310±20nm/1550nm±20nm wavelengths.

• FWDM Filter: The filter works as an optical coupler, separating light to be tested at different wavelengths.

• Optical Switches: OSW is a kind of optical path control equipment that connects multiple fibers under test. Based on thin film filter technology, it can transmit lights to the selected channel.

• Optical-time-domain-reflectometer: OTDR is designed for remote fault detection and isolation, fiber level fault monitoring, span level fault monitoring and long span monitoring. It

Besides the products mentioned, the FMT Series Chassis is also indispensable. The items are plug-in modules, which should be installed in FMT Series Chassis and controlled by the Network Management Unit.

The Key Values of FS Fiber Monitoring Solution

Remote and Online Monitoring System

The fiber optic monitoring system operates over a remote and online platform (FMT Series Optical Cable Monitoring Software). Operators can monitor from a centralized location, check important data, alarms and reports remotely, and ensure faster decision-making. The platform supports digital records and queries, which enhance data management efficiency.

Proactive Monitoring and Rapid Alerts

OPD reports to the monitoring center, and operators can view the status of all the monitored cables at any time via the online platform. The OTDR routinely monitors fiber performance, reducing the impact of unexpected faults on operations. Once there is an anomaly, users will receive alarms, which enables real-time fault warnings, faster issue resolution, and improves network reliability.

Figure 4: Cable Measurement

Accurate and Quick Fault Location

In Fiber Monitoring System, OPD measures the optical power and OTDR calculates the link length, link loss, ORL and fiber attenuation to test the whole links and locate breaks accurately. It greatly shortens the time of troubleshooting. Service providers can dispatch repair teams immediately to greatly reduce network downtime.

Compact and Highly Integrated Platform

FS offers a wide selection of 1U, 2U and 4U rackmount chassis that accommodate the monitoring cards. Each has 4 slots, 8 slots and 16 slots to realize high-density structure. As a part of the FMT Series, the monitoring cards can share the chassis with optical-layer and electrical-layer cards. Operators can manage OEO transponder, EDFA amplifier, OLP, OTDR, OPD, etc., in one chassis, which minimizes rack space and simplifies the deployment.

Flexible Application

The fiber optic monitoring system monitors up to 16 fibers and operates standalone over dark fibers or lit fibers. It can not only work with FS optical transmission equipment (FMT Series, MS8100 Series, M Series or D7000 Series) but also integrates with one from the third party, troubleshooting for P2P, P2MP or mesh networks. The device monitors the entire DWDM C-band spectrum and a section of CWDM wavelength, which can satisfy the monitoring needs of most optical networking.

Conclusion

As the deployment of fiber networks continues to progress, a fiber monitoring system is greatly helpful to ensure network quality and reliability. The fiber optic system is growing based on your application and budget, and FS will always develop cost-effective and innovative fiber optic solutions with customer-oriented principles. Contact us for more information.