Method and apparatus for conducting crypto-ignition processes between thin client devices and server devices over data networks

Abstract

A crypto-ignition process is needed to establish an encrypted communication protocol between two devices connected by an insecure communication link. The present invention introduces a method of creating an identical secret key to two communicating parties is conducted between a thin device and a server computer over an insecure data network. The thin device generally has limited computing power and working memory and the server computer may communicate with a plurality of such thin devices. To ensure the security of the secret key on both sides and reduce traffic in the network, only a pair of public values is exchanged between the thin device and the server computer over the data network. Each side generates its own secret key from a self-generated private value along with the received counterpart's public value according to a commonly used key agreement protocol, such as the Diffie-Hellman key agreement protocol. To ensure that the generated secret keys are identical on both sides, a verification process is followed by exchanging a message encrypted by one of two generated secret keys. The secret keys are proved to be identical and secret when the encrypted message is successfully decrypted by the other secret key. To reduce network traffic, the verification process is piggybacked with a session request from the thin device to establish a secure and authentic communication session with the server computer. The present invention enables the automatic delivery of the secret keys, without requiring significant computing power and working memory, between each of the thin clients respectively with the server computer.