Three-party semi-quantum dialogue enhanced with Grover’s algorithm based encoding and hypergraph access control

We introduce a new three-party semi-quantum dialogue (3P-SQD) protocol that combines GHZ-state-based semi-quantum communication, a Grover’s algorithm-driven 2-bit encoding scheme, and hypergraph-based access control. In each round, the fully quantum participant Alice sends two bits, whereas the semi-quantum participants Bob and Charlie, restricted to semi-quantum operations such as measurements in the computational basis and reflection, each transmit one bit. The protocol incorporates probe state checking, Grover’s algorithm-based encoding, and hypergraph-based authorization. It achieves information-theoretic security and controlled access, while preserving high message throughput and imposing no additional requirements on the semi-quantum users.