MASTERÂ Assignment
Unification of the framework of cross-user leakage in SSE
Type : Master M-CS
Period: March, 2024 - August, 2024
Student : Kampen, V. (Victor, Student M-CS)
Date Final project: August 28, 2024
Supervisors:
Abstract:
This thesis addresses the challenge of comparing security definitions for searchable symmetric encryption (SSE) which is when a party outsources the storage of his data to another party in an encrypted manner whilst still being able to search over it. It focuses on cross-user leakage, where the actions of one user leak information about the actions of or the data available to another user. We systematically review and clarify the implementations from four influential papers, introducing unified symbols and terminology to standardise protocols and security definitions. Key contributions include the development of a unified framework, the reformulation of security definitions, a new simulation-based security definition for the multi-key setting, and the proof that semantic security is equivalent to indistinguishability in the multi-key setting. The result of our work is a comprehensive unification of the SSE framework in the context of cross-user leakage, providing a clearer and more consistent foundation for future research.