A1 is a bend-insensitive single-mode optical fiber engineered specifically for access networks and FTTH deployments. Fully backward compatible with legacy G. D infrastructure, it supports full-band transmission from 1260nm to 1625nm. 652, which describes its characteristics, has been adapted to this experience. The experience with the installation and operation of single-mode fibre and. Bending losses are a function of the fiber type (SM or MM), fiber design (core diameter and NA), transmission wavelength (longer wavelengths are more sensitive to stress) and cable design. Among these, commonly used standards are G.