The present invention prevents a connection defect of a connector. The presence of another copy of the data item is determined, at least in part, based on an identifier for the data item, the identifier having been computed using all of the data in the data item and only the data in the data item, wherein two identical data items in the data processing system will have identical identifiers. Each CAM device of the serial cascade arrangement receives a portion of the search word. Moreover, the connection-oriented protocol can be the Transport Control Protocol, whereas the connectionless protocol can be the Universal Datagram Protocol.