Distribution Frames and Cabinets
The main distribution frame (MDF) is the interface between the subscriber cables coming in from all directions and the switching system. The subscriber cables and the system cables are all led and connected to the main distribution frame. The connection between both cable sides is implemented by jumpering. In addition to connecting and organizing all cables, the main distribution frame also provides protection against overvoltage and overcurrent for service technicians and the switching system itself. Subscriber and system cables can be both checked and disconnected in the main distribution frame; xDSL splitters for data transmission can be installed as well.
Main distribution frames are used wherever a large number of subscribers needs to be connected with the switching system, for example in networks of telecommunications providers or in large buildings such as banks, insurance companies and worldwide headquarters.