Method of secure anonymous query by electronic messages transported via a public network and method of response

摘要

A method for secure anonymous querying by a user of an information provider by electronic mail and for obtaining a reply uses a public key of the provider to form an electronic encrypted query package containing information including a query, a generated random number sequence, a hash of the query, a generated public key of the user, and an identification of a public bulletin board. The query package is preferably sent to the provider via a network from a public terminal. At the information provider the query package is received and decrypted. If the result of hashing the decrypted query is equal to the decrypted hash, a response R is formulated. A response package is formed therefrom by using a generated symmetric key of the information provider and the public key of the user. The response package is posted to the public bulletin board along with the random number sequence. The public bulletin board is accessed by the user in an anonymous manner and the response package, which is identified by the random number sequence, is downloaded and decrypted to obtain response R.