Identity Wallet in a Hostile Environment: Privacy and Trust By-Design

• Applicant: Dr.-Ing. Lucjan Hanzlik
• Subject Area: Security and Dependability, Operating-, Communication- and Distributed Systems
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 545066907

The project's primary objective is to design and conduct a theoretical security analysis of cryptographic protocols tailored to a practical identity ecosystem incorporating advanced features, notably one-time tokens. This identity system must uphold principles of trustworthiness, distribution, and privacy preservation, placing control in the hands of data subjects—the individuals to whom the processed data pertains. A key ambition is to establish end-to-end (E2E) security and privacy, even in the absence of trust in any protocol component or actor, including users and devices operating on the black box principle. This endeavor addresses crucial questions emerging from the impending eIDAS 2 Regulation, particularly examining the feasibility of the regulation's underlying concepts. The project will actively design cryptographic components essential for meeting the requirements outlined by the eIDAS regulation. The project is concentrated on the concept of the European Identity Wallet, certificates of attributes, privacy and security by-design, and verifiability. The project aims to develop cryptographic protocols solving the following key issues: Issue 1: finding lightweight solutions for one-time anonymous tokens. These tokens are issued for users with specific attributes known by the issuer and spent by users anonymously elsewhere. The challenge lies in creating solutions that ensure double-spending preventions and non-shareability of tokens while at the same time not requiring service providers to keep a shared state or use specialized and central identity infrastructure servers. Issue 2: address the threat to identity and attribute verification posed by malicious black box components. These components can covertly transmit data, establishing a malicious shadow ecosystem violating eIDAS and GDPR. The project aims to devise detection mechanisms and verifiability for key functionalities within the eIDAS framework. Issue 3: distributing the operations between different components – thereby replacing a single element (and a single-point-of failure) with a group of components executing multiparty protocol and resilient to failures of some of them. Issue 4: develop a theoretical model for a trust infrastructure, considering local sources of attributes, direct exchange of certificates by users, and enriching the framework of blind signatures and anonymous tokens. The main focus is on the formulation of "protocol complexity" as a model capturing bounds for implementability – just as the classical space, time, and communication complexity theory for the design of algorithms.

• DFG Programme: Research Grants
• International Connection: Poland
• Cooperation Partner: Professor Miroslaw Kutylowski