Punchdown Tools
If you have ever looked in a network closet, you have probably seen a distribution block, more commonly called a patch panel. A patch panel is a freestanding or wall-mounted unit with a number of port connections on the front. In a way, it looks like a wall-mounted hub without the light-emitting diodes (LEDs). The patch panel provides a connection point between network equipment such as hubs and switches and the ports to which PCs are connected, which are normally distributed throughout a building.
Behind each of the individual RJ-45 jacks on the patch panel are connectors to which are attached the eight wires from a piece of twisted-pair cable. These wires are commonly attached to the patch panel by using a tool called a punchdown tool. To use the punchdown tool, you place the wires from the cable into the appropriate slots in the back of the patch panel, and then use the tool push the wires firmly down into the slots. The insulation is stripped, and the wire becomes firmly embedded into the connector. Because the connector strips the insulation on the wire, it is known rather grandiosely as an insulation displacement connector (IDC).