System and method for restricting access to a terminal

A method for authenticating data comprising the steps of: providing data to a first device having at least two initial cryptographic keys; generating authentication information required to authenticate the data utilizing the at least two initial cryptographic keys; sending the data and authentication data to a second device having paired cryptographic keys wherein each paired cryptographic key is associated to one of the at least two initial cryptographic keys; and authenticating the data in the second device utilizing the paired cryptographic keys.