Secure Wire Shuffling in the Probing Model

. In this paper we describe the first improvement of the wire shuffling countermeasure against side-channel attacks described by Ishai, Sahai and Wagner at Crypto 2003. More precisely, we show how to get worst case statistical security against t probes with running time O ( t ) instead of O ( t log t ) ; our construction is also much simpler. Recall that the classical masking countermeasure achieves perfect security but with running time O ( t 2 ) . We also describe a practical implementation for AES that outperforms the masking countermeasure for t ≥ 6 000 .