1. A method of erasing a volatile memory requiring refreshment using a refresh circuitry to maintain data storage, the erasure method comprising: controlling the refresh circuitry for preventing the refreshment of the memory at the occurrence of a predefined event, wherein the volatile memory is one or more memory banks of a dynamic random access memory (DRAM) and is connected to a processing unit accessible by multiple users, processes, applications or services; and wherein the predefined event is before switching between a first user, process, application or service and a subsequent user, process, application or service such that any data stored inside the memory by the first user leaks by the effect of the memory refreshment prevention before the subsequent user, process, application or service is provided access to the memory; and the refresh circuitry is a DRAM controller, and wherein the controlling includes: receiving and storing addresses of memory banks, and restricting access operations to these memory banks during a restriction time period that provides sufficient time for allowing leakage of data in the memory banks by preventing the refreshment of the memory, and once the restriction time period is completed, resuming the refreshment of the memory.