A system and method for authenticating an authentication requesting device (ARD) is disclosed. The system is configured to provide validation encryptions (VEs) for each given device of devices, each given encryption of the VEs being encrypted using an encryption function (EF) using a derived key (DK) generated from a currently used root key (RK) of the respective given device using a derivation function (DF) designed to generate a different derivation for identical data for each execution; obtain an authentication encryption (AE) generated by the ARD and a timestamp indicative of a time of creation of the AE, the AE being encrypted using the EF using an ARD DK generated from the currently used ARD RK, and wherein the ARD DK is generated using the DF; and authenticating the ARD only if one of the VEs matches the AE and the timestamp is within an allowed time window.