Techniques for authenticating the identity and validating the profile of an individual (“a presenter”) who presents him or herself to another party (“an acceptor”) as having a certain identity and having certain corresponding profile data are described. The invention can be advantageously used in Internet transactions where such authentication and validation is difficult to perform. The techniques of the present invention allow the trusted party to give a definitive answer regarding the authentication of identity and validity of profile data. Other services such as profile data provisioning and profile data updating can also be performed.