A system for securing a transaction comprises an authentication unit capable of processing an input and generating a dynamic card transaction code/virtual card code which is valid for a single transaction upon authentication; and a RFID generator capable of generating at least a dynamic RFID key for a predefined limited time period by using the dynamic card transaction code for the single transaction. The authentication of the input is performed locally with the authentication unit through an encrypted and unique RFID communication between the authentication unit and a third party by using a challenge response protocol. The authentication unit is capable of working alone and as a plug-in with at least any one of a personal digital assistant (PDA), a hand-held remote control, a cellular telephone, a fax machine, and a printer is used for securing the transaction.