Patent ID: 7218733

Claim:
A digital encryption method which uses an encryption algorithm for executing data processing, the method comprising: providing initial values to be applied in the encryption algorithm; inputting a common key K and a plaintext P; generating an internal key related to and based on the common key K; providing plaintext information comprising processed plaintext P data or the plaintext P; generating a primary ciphertext E 1 for the plaintext P by performing a first exclusive OR operation between the plaintext information and the internal key; generating a secondary ciphertext E 2 for the plaintext P by performing a second exclusive OR operation between the primary ciphertext E 1 and data V for secondary encryption; defining a group of data to be handled with the encryption algorithm comprising the common key K, the plaintext P and the initial values or the common key K, the plaintext P and data generated by processing the initial values, and providing the group of data as a virtual data space, wherein the second exclusive OR operation is recognized as a vector directional component designating data in the virtual data space, and wherein the data designated by the vector directional component is recognized as a vector quantitative component; performing a logical operation for the vector quantitative component for generating vector data; and using the vector data as the data V for secondary encryption.