Improved Cryptanalysis of the Self-Shrinking Generator
We propose a new attack on the self-shrinking generator . The attack is based on a backtracking algorithm and will reconstruct the key from a short sequence of known keystream bits. We give both mathematical and empirical evidence for the effectiveness of this attack. The algorithm takes at most O(20.694L) steps, where L is the key length. Thus, our attack is more efficient than previously known key reconstruction algorithms against the self-shrinking generator that operate on short keystream sequences.
KeywordsSearch Tree Stream Cipher Independent Equation Linear Feedback Shift Register Left Child
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