Abstract: Method for decreasing the existence of externally detectable revealing signals, so-called {umlaut over (R)}Ö{umlaut over (S)}, from keyboards (1), e.g. for computers, where the keyboard is fed with signals, so-called matrix signals, which are detected for detection of activity regarding the keys (2) of the keyboard, whereby said matrix signals are generated by means of signal devices. The method is especially characterized in that the matrix signals are high-frequency filtered before they are fed to the keyboard.

Abstract: System for administrating at least one electronic document, the system comprising: a communication terminal (105) adapted for communication with a server (115) via a network (110), said server being adapted for communication with a database (120), wherein the electronic document comprises a first information entity and a second information entity, wherein the communication terminal (105) is arranged to display the first and the second information entity in dependence of each other and to provide information to the second information entity, wherein said communication terminal further is arranged to generate a third information entity comprising at least part of the first and second information entity and the provided information by converting means, wherein said communication terminal further is arranged to make the third information entity unique, and wherein said server is adapted to transmit at least a part of the unique third entity to a receiving unit (120; 130).

Abstract: A method and a device for carrying out electronic transactions. A sender produces, under his own full control, a transaction message in a smart card (1) and provides the message with his digital signature in the card for subsequent output and transmission.