Optical fiber cables for indoor cabling are used for the construction of horizontal subsystem and SCS building backbone cabling subsytems. They differ from cables used for outdoor cabling by two key parameters.

Indoor fiber optic cable is tight buffer design, usually they consist of the following components inside the cable, the FRP which is non-metallic strengthen member, the tight buffer optical fiber, the Kevlar which is used to further strength the cable structure, making it resist high tension, and the cable outer jacket. The trend is to use LSZH or other RoHS compliant PVC materials to make the cable jacket; this will help protect the environment and the health of the end users.