Patent ID: 7418100

Claim:
A data communication method, comprising the computer-implemented steps of: receiving, over an electronic digital telecommunication link that couples a sender and receiver to one another, a first message comprising input plaintext data; separating the plaintext data into a first plaintext data segment and a second plaintext data segment; encrypting the first plaintext data segment using block cipher encryption and a first key, resulting in creating a first encrypted segment; applying an exclusive OR operation to the first encrypted segment and a hash of the second plaintext data segment and an associated data element based on a second key, resulting in creating a first intermediate result datum; applying an encryption operation to the first intermediate result datum and a third key, resulting in creating an encryption output; applying an exclusive OR operation to the encryption output and the second plaintext data segment, resulting in creating a second intermediate result datum; applying an exclusive OR operation to the first intermediate result datum and a hash of the second intermediate result and the associated data element using a fourth key, resulting in creating a third intermediate result datum; and creating, as an output ciphertext, a concatenation of the second intermediate result datum and a decryption of third intermediate result datum using a fifth key; sending the output ciphertext to the receiver over the link in a second message; wherein each of the plaintext data, segments, intermediate result data, associated data, and ciphertext is a digital value stored in an electronic digital memory device; wherein the separating, encrypting, applying, and creating operations are performed in an electronic digital data processing apparatus coupled to the electronic digital memory device and interacting with the digital data values.