Abstract: A variable resistor, a nonvolatile memory device and methods of fabricating the same are provided. The variable resistor includes an anode electrode and a cathode electrode, a variable resistive layer including CdS nanoscale particles provided between the anode electrode and the cathode electrode, and an initial metal atom diffusion layer within the variable resistive layer. The variable resistor is a bipolar switching element and configured to be in a reset state when a positive voltage relative to a cathode electrode is applied to the anode electrode, and configured to be in a set state when a negative voltage relative to the cathode electrode is applied to the anode electrode.

Abstract: A system and method for authenticating a resource-constrained client are provided. The method includes transmitting, by the server, a query message including a first modified secret key to the client, wherein the first modified secret key is generated using a first secret key and a first blinding value; receiving, from the client, a response message including a response value, wherein the response value is generated using the first blinding value, a second secret key, and an error value; calculating the error value from the response value; and determining, based on the error value, whether authentication of the client is successful.