On the Relationship between Physical and Non-physical Secure Computation Protocols

Reference No.	2023a009
Type/Category	Grant for Young Researchers and Students- Short-term Visiting Researcher
Title of Research Project	On the Relationship between Physical and Non-physical Secure Computation Protocols
Principal Investigator	Kazumasa Shinagawa（Ibaraki University・Assistant Professor）
Research Period	September 19,2023. ～ September 29,2023.
Keyword(s) of Research Fields	Secure computation, Card-based protocols, Private simultaneous messages.
Abstract for Research Report	Secure computation allows multiple players with private inputs to compute a function of their inputs while keeping each player's input hidden from the other players. There are two types of secure computation: physical secure computation, which utilizes physical objects such as cards or envelopes, and non-physical secure computation, which is intended to be implemented on electronic computers and does not rely on physical objects. Until recently, physical and non-physical secure computation were considered separate research fields, and the application of physical secure computation techniques to non-physical secure computation was not well understood. However, in our previous project "On Minimal Construction of Private Simultaneous Messages Protocols," we showed that any card-based protocol, a type of physical secure computation protocol, could be converted to a private simultaneous messages (PSM) protocol, a type of non-physical secure computation protocol. In this project, we aim to further explore the relationship between physical and non-physical secure computation. Specifically, we plan to establish a more rigorous relationship between card-based protocols and PSM protocols by determining the efficiency of conversion and the required conditions for conversion. Furthermore, we intend to generalize our results to identify a class of physical secure computation protocols that can be converted to non-physical secure computation protocols.
Organizing Committee Members (Workshop) Participants (Short-term Joint Usage)	Kazumasa Shinagawa（Ibaraki University・Assistant Professor）
Adviser	Koji Nuida (Kyushu University, IMI / Professor)