The Critical Role of Automated Testing for Data Center Interconnects

As the demand for data center capacity grows, hyperscale operators are quickly expanding their facilities. It’s crucial for these operators to have strong interconnects that allow them to effortlessly extend their rack space throughout a campus, without affecting current services or network reconfiguration. Typically, these interconnections are made using high-density fiber placed in underground channels between data halls. To ensure a smooth expansion of your data center infrastructure, validating the performance of these interconnects with effective testing methods is essential.

Leveraging Trunk Cables with MPO Connectors

To facilitate fast, plug-and-play style connections between new and existing data halls, hyperscale providers are turning to pre-terminated trunk fiber cables. These high-density cables utilize multi-fiber push-on (MPO) connectors, which can mate multiple fibers at once. This allows operators to swiftly install networks using factory-terminated cable assemblies.

The Importance of OTDR Testing

For short-distance in-hall links, basic insertion loss testing with an Optical Loss Test Set (OLTS) may be sufficient. However, longer stretches across campuses or between buildings often require more detailed tier 2 testing which utilizes Optical Time Domain Reflectometers (OTDRs). As these hyperscale interconnects grow in capacity and distance, having optimised OTDR testing workflows is indispensable. Often you will find other methods lack in the features you need.

While OLTS testing only measures total end-to-end loss, OTDR testing provides comprehensive characterisation of the fiber span. Light pulses are sent through the fiber, analyzing the reflected signatures. This effectively maps the precise locations of events such as splices, breaks, bends and connectors along the line.

For Data Center Interconnects using pre-terminated cables, OTDRs allow operators to qualify manufacturer specifications, detect any shipping damage and certify installation practices. OTDR trace analysis also validates uniformity of multi-fiber links, identifying any strand with degraded performance.

The Challenges of Manual Testing

While OTDR testing provides invaluable data, it can be extremely cumbersome and time consuming if the technology does not support automated testing of MPO-terminated links.,

Manually connecting and configuring OTDRs to test each fiber within an MPO via fan-out cables adds time and risk of human error. Scaling manual OTDR testing methods to meet hyperscale interconnect demands on the face of things can appear impractical due to the time and expense involved.

Optimizing Testing Workflows Through Automation

This is where AFL’s experience and breadth of available technology portfolio offers transformative improvements to OTDR testing. By leveraging our OTDR testing solutions in conjunction with MPO switching and some clever control commands, technicians can configure the test set-up once, which streamlines and automates sequential testing across the entire array of fibers in an interconnect. Tests are performed rapidly with uniform parameters across all fibers in the MPO connector.

Automating the repetitive tasks not only improves speed and reduces labor requirements, it also reduces risks of human error and inconsistency. All resulting data can then be stored centrally for convenient monitoring and documentation. Testing workflows are optimised end-to-end.

As hyperscale interconnect capacities continue to accelerate, rapid testing will become critical. Partnering with companies such as AFL to deliver innovative solutions that speed up testing will empower operators to scale efficiently. This ensures fiber infrastructure is validated, problems are prevented proactively, and the highest standards of performance, reliability and availability are maintained.