18. A knowledge-based authentication method performed by a server for restricting access of a user to a restricted resource, comprising the steps of: receiving a plurality of answers from said user during a set-up phase to a set of personal questions, wherein at least one of said answers received from said user encode one or more of historical, inter-relational and contextual information of said user using an encoding scheme defined between said server and said user to signal a fraudulent access attempt; challenging said user with one or more questions from said set of personal questions; receiving a response from said user to said one or more questions from said set; assigning a score to said response, wherein said score is based on said encoded information; and granting access to said restricted resource based on said score, wherein at least one of said steps are performed by at least one hardware device.
18. A knowledge-based authentication method performed by a server for restricting access of a user to a restricted resource, comprising the steps of: receiving a plurality of answers from said user during a set-up phase to a set of personal questions, wherein at least one of said answers received from said user encode one or more of historical, inter-relational and contextual information of said user using an encoding scheme defined between said server and said user to signal a fraudulent access attempt; challenging said user with one or more questions from said set of personal questions; receiving a response from said user to said one or more questions from said set; assigning a score to said response, wherein said score is based on said encoded information; and granting access to said restricted resource based on said score, wherein at least one of said steps are performed by at least one hardware device. 19. The method of claim 18 , further comprising the step of repeating said set-up phase to update one or more of said set of personal questions, said corresponding answers and said encoded historical, inter-relational or contextual information of said user.