d-Functions in Vk(F2) and self-decimation of m-sequences
With the purpose of generating, by the help of a single clock-controlled LFSR, a large class of binary sequences strong enough for cryptographic application, an extension class of key-specifiable transfer functions is proposed and analyzed. When tapped as feedforward networks to the LFSR under consideration, these functions will control the stepping of the latter in such a way that its output signals will be decimated pseudo-randomly at a pre-assigned rate. The decimation rate and the length of the LFSR are then suitably selected so that the resulting sequence will have, among others, a large prime period and a linear complexity comparable in order of magnitude to the period. Some conclusions concerning the average and maximal implementable decimation rates are also given.
KeywordsBinary Sequence Linear Complexity Output Sequence Delay Element Prime Period
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