Equipment used on end-user lines or trunk lines and capable of provisioning and connecting them. The distribution frame is the most important component in the management subsystem, and it is the hub to realize the cross-connection of the two subsystems of vertical trunk line and horizontal wiring. Patch panels are usually mounted on cabinets or walls. By installing accessories, the distribution frame can fully meet the needs of UTP, STP, coaxial cable, optical fiber, audio and video. The distribution frames commonly used in network engineering include twisted pair distribution frames and fiber optic distribution frames. According to different places and purposes, it can be divided into two categories: main distribution frame and intermediate distribution frame.