Cost-Effective and Practical Countermeasure against the Template Side Channel Attack

One of the most efficient attacks for exploiting the secret key is a template attack. Recent researches show that regular countermeasures against these attacks are costly. Randomized shuffling in the time domain is known as a cost-effective countermeasures against side-channel attacks are widely used. In this article, we implemented a real template attack and proposed an efficient countermeasure against it. We practically evaluated security improvement with this method in the AES algorithm on a template attack and reported the analysis results of our countermeasure. According to these results, template attack will be hardened significantly after the proposed protection such that the grade of the key recovery increases from 1 with 350K traces in unprotected design to 2
¹⁰⁰
with 700K traces in the protected circuit. This security improvement gains in the cost of about 7% delay overhead.