Patent ID: 6947560
Filing Date: 2005-09-20
Classification: G06Q,H04L

Abstract:
1. A communication device for calculating an encryption key, K′ c , by manipulating a ciphering key, K c , for use in an encryption algorithm, said device comprising: a memory element for storing one or more polynomials; a plurality of switching elements, each having a first input, a second input and an output, wherein said switching elements first inputs are connected to said memory element; a plurality of delay elements, each having an input and an output, where said output of one of said delay elements is connected to said switching elements second inputs; and a plurality of addition functions, each having a first input, a second input and an output, wherein: the outputs of each of all but one of said delay elements is connected to a corresponding first input of one of the plurality of addition functions, the outputs of each of all but one of said switching elements is connected to a corresponding second input of one of the plurality of addition functions, and the inputs of each of all but one of said delay elements is connected to a corresponding output of one of the plurality of addition functions.