Controlling access to a secure server from a remote computer

Controlling access to a secure server from a remote computer including the steps of transmitting a verification signature and state information containing an authorisation variable to the remote computer. The verification signature and state information are subsequently included in requests for information sent from the remote computer to the secure server. The secure server extracts the authorisation variable from the received state information and either processes the request if the authorisation variable matches the value stored at the server, or transmits a new authorisation variable to the remote server if the received authorisation variable was empty.