Abstract: Method and system for securing a data system (1) that is connected to other systems by communication means (5) and exchanges data with these other systems via said communication means. The most recently exchanged data is continuously buffered in buffer devices (2, 3). The normal operation of the data system is monitored by a monitoring device (6) that in the event of an abnormality in the operation of the data system activates an output device (7) in order to read out the buffered data from the buffer devices and to make these data available for analysis.

Abstract: A method and system for filtering data in a network is provided. Initially a content type of data is determined, and if the content type is one of a number of predetermined content types, then a series of checks may be made. For example, the content syntax of the data may be determined and the content semantics of the data may be determined. The content syntax may be checked against a predetermined set of syntax rules corresponding to the predetermined content type and the content semantics may be checked against a predetermined set of semantic rules corresponding to the predetermined content type. If the content syntax and the content semantics satisfy the predetermined rules, then the data may be further processed. If the content syntax and the content semantics do no satisfy the predetermined rules, then the data may be discarded.