Secure Three-Party Semi-quantum Summation Using Single Photons

We first propose a three-party semi-quantum summation protocol with an almost-dishonest third party (TP) using single photons. TP who has full quantum power helps three classical users compute the summation of their private bit strings while the privacy of their inputs is preserved. For a particle from TP, three users’ operations are limited either to (1) reflect the particle without disturbance back to TP or to (2) measure the particle in the Z basis and resend the measured particle back to TP. We also show that our protocol is secure against both outside and participant attacks.