Patent ID: 8688996

Claim:
A method for encrypting a plaintext message, the method comprising: (a) encrypting a message using a first key associated with a first party or a first device, to obtain a first encrypted message; (b) sending, by the first device the first encrypted message to a second party or a second device; (c) receiving a second encrypted message that has been encrypted using a second key associated with the second party or the second device, wherein the second encrypted message has been encrypted using both the first and second keys; (d) decrypting the second encrypted message using the first key to obtain a third encrypted message that has been encrypted using the second key; (e) encrypting the third encrypted message using a third key associated with the first party or the first device to obtain a fourth encrypted message that has been encrypted using the second and third keys; (f) sending the fourth encrypted message to the second party or the second device; (g) receiving a fifth encrypted message that has been decrypted using the second key and encrypted by a fourth key associated with the second party or the second device, wherein the fifth encrypted message has been encrypted using the third and fourth keys; (h) decrypting the fifth encrypted message using the third key associated with the first party or the first device, to obtain a sixth encrypted message encrypted by the fourth key associated with the second party or the second device; (i) sending the encrypted plaintext message encrypted by the fourth key to the second party or the second device for decryption using the fourth key to obtain the plaintext message.