Abstract: For an Elliptic Curve Scalar Multiplication (ECSM) operation to be performed on a scalar and a base point, a given previous set of parameters that was used to split the scalar for a previous ECSM operation and a selected random integer are used to determine a new set of parameters for splitting the scalar. By basing the new set of parameters on the previous set of parameters, repeated use of the scalar to determine key-splitting parameters is avoided and susceptibility to a Differential Power Analysis Side Channel attack is minimized.

Abstract: When multiplicative splitting is used to hide a scalar in an Elliptic Curve scalar Multiplication ECSM operation, the associated modular division operation employs the known Almost Montgomery Inversion algorithm. By including dummy operations in some of the branches of the main iteration loop of the Almost Montgomery Inversion algorithm, all branches of the algorithm may be viewed, from the perspective of a Power Analysis-based attack, as equivalent and, accordingly, devoid of information useful in determining the value of the scalar, which may be a cryptographic private key.

Abstract: A public key for an Elliptic Curve Cryptosystem is generated in a manner that acts as a countermeasure to power analysis attacks. In particular, a known scalar multiplication method is enhanced by, in one aspect, performing a right shift on the private key. The fixed-sequence window method includes creation and handling of a translated private key. Conveniently, as a result of the right shift, the handling of the translated private key is made easier and more efficient.