A complete Classification of Quantum Public-key Encryption Protocols
This work provides a foundational classification for researchers in quantum cryptography, identifying feasible and impossible protocol types to guide future research.
The authors tackled the problem of classifying quantum public-key encryption protocols by categorizing them into 64 types based on whether elements like plaintext or keys are quantum or classical, finding that 8 types are constructed, 52 are impossible, and 4 remain unproposed.
We present a classification of quantum public-key encryption protocols. There are six elements in quantum public-key encryption: plaintext, ciphertext, public-key, private-key, encryption algorithm and decryption algorithm. According to the property of each element which is either quantum or classical, the quantum public-key encryption protocols can be divided into 64 kinds. Among 64 kinds of protocols, 8 kinds have already been constructed, 52 kinds can be proved to be impossible to construct and the remaining 4 kinds have not been presented effectively yet. This indicates that the research on quantum public-key encryption protocol should be focus on the existed kinds and the unproposed kinds.