This document outlines the specifications for a single-mode optical fiber and cable designed for use around the 1310 nm zero-dispersion wavelength, suitable for both the 1310 nm and 1550 nm regions, and compatible with analogue and digital transmission. 652 fiber is the most commonly used. Whether it is a long-distance network, local network, or access network, it is the absolute protagonist, accounting for more than 95% of its overall. The ITU-T G. This is the latest revision of a Recommendation that was first created in 1984 and deals with some relatively minor modifications.
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