The Automated Cryptanalysis of DFT-Based Speech Scramblers

摘要

An automated method for cryptanalysis of DFT-based analog speech scramblers is presented through statis- tical estimation treatments. In the proposed system, the cipher- text only attack is formulated as a combinatorial optimization problem leading to a search for the most likely key estimate. For greater efficiency, we also explore the benefits of genetic algo- rithm to develop an estimation method which takes into account the doubly stochastic characteristics of the underlying keyspace.