A structural analysis of the A5/1 state transition graph

@inproceedings{Beckmann2012ASA,
  title={A structural analysis of the A5/1 state transition graph},
  author={Andreas Beckmann and Jaroslaw Fedorowicz and J{\"o}rg Keller and Ulrich Meyer},
  booktitle={Conference on Computer Graphics and Interactive Techniques in Australasia and Southeast Asia},
  year={2012}
}
We describe efficient algorithms to analyze the cycle structure of the graph induced by the state transition function of the A5/1 stream cipher used in GSM mobile phones and report on the results of the implementation. [] Key Method This step does not break the overall structure of the graph and keeps at least one node on every cycle. In the third step the nodes of the reduced graph are connected by weighted edges.

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