ABSTRACT
In the context of Federated Learning, it is essential to authenticate the incoming messages from various entities. Many works have utilized Certificateless Public Key Cryptography (CL-PKC) and Signature Schemes. These recent developments focus on the existence of a single Trusted Authority (TA) that can issue partial private signatures truthfully without any malicious intent. This assumption is not pragmatic when multiple competing entities with some assets are involved. Additionally, dependence on a single TA introduces a single point of failure and a center of malice. In this work, we first propose a mechanism for partial key exchange for CL-PKC employing Traceable Ring Signatures. Furthermore, we utilize the existing blockchain or logging infrastructure to extend our model to provide accountability and disincentivization for malicious TAs. The cryptographic tools used in this work can be parallelized to get more efficiency out of these trusted nodes. To evaluate our protocol, we also simulate it to argue for the communication and computation costs.
