Efficient Countermeasure for Securing the Eta Pairing Computation over Binary Fields

Pairing based cryptosystems have became suitable for use on constrained devices with small resources. Recently, It has shown that side channel attacks are a serious threat for such cryptographic applications. In order to secure the pairing based cryptosystems against the side channel attacks, many countermeasures have been proposed but their cost is proved to be highly expensive. In this paper, we propose a new technique for securing the eta pairing ηT over binary fields K = F2m . The main idea of the proposed countermeasure is the use of the randomized values x+ fi(r), where x is a variable involved in the computation of eta pairing, fi is a polynomial function, and r is a random integer in F2m . The overhead cost of the proposed countermeasure is only (m + 1)/2 field multiplications which makes it the most efficient known countermeasure for securing eta pairing against the side channel attacks over binary fields.