报告时间：8月21日 周二 下午3:00
报告人：张佳瑜 博士 （美国波士顿大学）
报告题目： Quantum Computation Delegation and KDM Security in Quantum Random Oracle Model
In this paper, we construct a new scheme for delegating a large circuit family, which we call "C+P circuits". "C+P" circuits are the circuits composed of Toffoli gates and diagonal gates. Our scheme has some different properties from the previous schemes based on quantum one time pad. Our scheme is non-interactive, only requires small quantum resources on the client side, and can be proved secure in quantum random oracle model, without relying on additional assumptions, for example, the LWE assumption. In practice the random oracle can be replaced by some plausibly candidates for appropriate hash functions, for example, SHA-3, AES.
This protocol allows a client to delegate the most expensive part of some quantum algorithms, for example, Shor's algorithm, while classical delegation protocols are not sufficient to delegate Toffoli gates on quantum state. The quantum resources required on the client side is less than that when it runs Shor's algorithm locally.
As part of our analysis, we study the key dependent message (KDM) security in quantum random oracle model(quantum ROM). We define the quantum KDM security, and construct a quantum KDM secure encryption scheme that encrypt quantum data using classical keys. We prove the security of our scheme in quantum ROM. KDM security was not previously studied in quantum settings.