Note the fibres are all straight lines between "events", as splices and connectors are called in OTDR jargon. Markers for loss measurements should always be set far enough on either side of an event to be on the straight part of the fibre trace. OTDR (Optical Time Domain Reflectometer) testing is a vital technique for characterizing and troubleshooting optical fiber networks. For municipal utilities, which are increasingly building and operating their own fiber optic infrastructures, the professional implementation of OTDR measurements is becoming a decisive success. If some critical fiber links exceed the application's loss budget, however, you'll need to troubleshoot. However, without knowing how to perform an OTDR test correctly, you risk getting inaccurate dB readings, leading to project delays.
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