Cold isn't the real threat: The glass strands rarely freeze, but moisture that seeps into connectors can freeze and cause damage. Optical fiber must be robust enough to cope with being run between communications masts for telecoms links, across freezing ground for television outside broadcasts, and alongside roads to carry video from traffic cameras. One specific problem is how the fibers and connectors cope with sub-zero. While the fibers themselves are protected by an acrylic layer, the connectors joining each fiber can be vulnerable in harsh environments. The actual glass or plastic inside the cable that transmits the data is not affected by cold temperatures. The wide application of fiber-to-the-home (FTTH) has promoted the rise of fiber optic fast connectors/cold connectors.
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