Abstract: Techniques are described for managing master keys for token requestors to use in generating cryptograms such as TAVVs. A processor computer generates a first master key for a token requestor, the first master key being generated based on (a) a second master key managed by the processor computer and (b) an identifier of the token requestor. The processor computer transmits, to a token requestor computer corresponding to the token requestor, the first master key. The processor computer receives, from the token requestor computer, a request for a token. Responsive to receiving the request for the token, the processor computer transmits the token to the token requestor computer; and receives, from the token requestor computer, an authorization request message comprising the token and a cryptogram generated by the token requestor computer using the first master key and the token.

Abstract: Techniques are described for managing master keys for token requestors to use in generating cryptograms such as TAVVs. A processor computer generates a first master key for a token requestor, the first master key being generated based on (a) a second master key managed by the processor computer and (b) an identifier of the token requestor. The processor computer transmits, to a token requestor computer corresponding to the token requestor, the first master key. The processor computer receives, from the token requestor computer, a request for a token. Responsive to receiving the request for the token, the processor computer transmits the token to the token requestor computer; and receives, from the token requestor computer, an authorization request message comprising the token and a cryptogram generated by the token requestor computer using the first master key and the token.

Abstract: A method for displaying images on a display having backlight is disclosed, where the images is updated periodically with a period. The method comprises the steps of: generating a signal with a pulse pattern for each period depending on the contents of an image to be displayed in that period; and activating backlight in accordance with the signal. Further, a display (100) comprising a display panel (102) and a backlight unit, wherein the backlight unit comprises a controller (104) and a lighting device is disclosed. The controller (104) is arranged to generate a control signal, and the lighting device is arranged to provide backlight to the display panel (102) according to the control signal, wherein the control signal comprises a pulse pattern depending on contents of displayed images.