Patent ID: 6948067
Filing Date: 2005-09-20
Classification: H04L

Abstract:
1. A method for encrypting and authenticating data as a single entity, comprising: arranging data into a plurality of plaintext blocks, each sized according to a cipher block size; specifying at least one cleartext position for which at least one ciphertext block will be the same as a corresponding plaintext block; determining a plurality of noise blocks using a nonce value and a first key; determining a plurality of intermediate ciphertext blocks, wherein the first intermediate ciphertext block corresponds to an encryption of the nonce, and the remaining intermediate ciphertexts are determined by: determining a plurality of ciphertext blocks, wherein the plurality of ciphertext blocks are determined by: determining a plurality of authentication blocks, wherein the plurality of authentication blocks are determined by: computing an authentication tag by combining all of the plurality of authentication blocks with a noise block and then encrypting the combined result; and appending the authentication tag to the plurality of ciphertext blocks.