Performance of optical fiber connectors can be quantified by insertion loss and return loss. Whether you're planning an FTTH deployment, upgrading a data center, or working in telecom infrastructure, this guide will help you make informed decisions when choosing fiber connectors. Ensures low return loss (minimal light reflection back into. Selecting the right fiber optic connector in accordance with current IEC standards is crucial to the performance, reliability and future-proofing of a fiber optic infrastructure. Each day new devices, software apps and applications are brought to the market which produce even more data. Structured inspection (end-face microscopy), testing (IL/RL, continuity), and proper cable management.