Abstract: A method for providing publicly verifiable translation certificates comprising the steps of receiving an input encryption having a first secret key; outputting an output re-encryption of the input encryption, the output re-encryption having a second secret key; and generating a translation certificate that proves the input encryption and the output re-encryption are encryptions of an identical message, wherein the first secret key and the second secret key do not need to be, but are allowed to be, equal. This method and system for generating translation certificates in quorum controlled asymmetric proxy encryptions has uses, including but not limited to, Internet applications and specifically to E-mail systems.

Abstract: A method of forwarding an encrypted message sent to a primary recipient having a secret key to at least one secondary recipient comprising the steps of sharing portions of the secret key among a predetermined threshold number of proxy servers greater than one, upon receipt of an encrypted message by the predetermined threshold number of proxy servers, each of the predetermined threshold number of proxy servers modifying the message by applying the key portion to the encrypted message, the result of the modification comprising a message secret to the predetermined threshold number of proxy servers but decryptable by at least one secondary recipient, and forwarding the resultant message to at least one secondary recipient. This method and system for quorum controlled asymmetric proxy encryption has uses ranging from efficient key distribution for pay-tv, to methods for distributively maintaining databases.