Patent attributes
An order-preserving tokenization (OPT) method receives a plaintext and generates a token as the ciphertext which preserves the sort order of the plaintext by using stored legacy plaintext-to-ciphertext mapping data and a tail bounded probability distribution sampler to sample a random order preserving function. More specifically, the OPT method uses a mapping table to store plaintext-to-ciphertext mapping for previously generated ciphertexts. The mapping table enables efficient searching of the ciphertext space as the OPT method only needs to look for ciphertext in the space that most likely will have the desired plaintext. In this manner, the order-preserving tokenization method of the present invention realizes a fast algorithm that is also more computational efficient. In one embodiment, the OPT method uses a tail bounded hypergeometric distribution sampler as the probability distribution sampler.
