Abstract: The plugging apparatus, may such be a plug and/or a socket has a plurality of terminals or plug contact sockets. These serve for the transmission of electrical energy and include light wave conductors integrated therein for the transmission of optical information signals via one and the same plugging apparatus.

Abstract: In order to determine the identity and authorization of a key which is inserted into a cylinder lock, the key is provided with an information carrier with elements which are magnetically passive and inductively readable and yield permanently stored information. The carrier is fixed to the key blade. A reading head mounted in the lock reads the carrier as the key is moved into or out of the lock. An electronic evaluation circuit uses a micro-processor to interpret the information. The carrier is so designed that alterations made in it after it is coded are immediately detected by the evaluation circuit. A particular relationship of the reading head to the information carrier is described for a particular pattern of loop-shaped information elements on the carrier.