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. All three fiber types are characterized as “ low‑water peak ”, meaning the maximum attenuation requirement at 1383 nm is equivalent to the maximum attenuation specified at 1310 nm. It details the fiber's geometrical, optical. ic system. Fiber optic testing of a newly installed system not only verifies that the system meets its design requirements, but also creates a performance baseline for all future testing and troubleshooting of t at system. It can be used in all cable constructions, including loose tube, tight buffered, ribbon, and.