Patent ID: 7206803

Claim:
A computer implemented method for controlling access to protected contents on a server using a mobile security module, the computer implemented method requiring the following components to be present: a) a server; b) a client; c) a reader for a mobile security module; d) a mobile security module associated with the client and having at least one protected area for storing a key; and e) a data line for communications between client and server; and wherein the computer implemented method comprises the following steps: aa) sending to the server of a request to call up protected-access contents; bb) sending from the server to the client of an authentication module to be run in the client; cc) execution of an authentication protocol for authenticating the mobile security module and, where appropriate, its holder by means of the authentication module, wherein the authentication protocol is executed in the followed steps: generation of a random number by the server application when the content requested is access-protected and the requirements for access have not been satisfied, and sending of the random number to the authentication module; sending of the random number from the authentication module to the mobile security module; generation in the mobile security module of a digital signature which takes account of the identity number of the mobile security module, the random number and the key of the mobile security module, wherein the digital signature is generated by means of a symmetrical encryption algorithm with the help of a secret key agreed between client and server, or by means of an asymmetrical encryption algorithm with the help of a private key, the server being in possession of the public key; sending of the digital signature to the server; and checking of the correctness of the digital signature using the securing module of the server; dd) if the authentication in step cc) was successful, addition to the request in step aa) of a session ID which was generated in the course of the communications between the authentication module and the server; ee) sending of the new request to the server application; ff) checking of the session ID in the request to see that it is recorded in the server; gg) processing of the content requested for transmission and searching of the contents for further links to other protected-access contents; hh) addition of the session ID to the links identified; and ii) sending of the content modified as in step hh) to the client.