An accountable privacy-preserving scheme for public information sharing systems

Abstract

Due to the emergence of data externalization technologies, as cloud and fog computing, setting up public information-sharing applications has become much easier. Yet, many concerns related to information security need to be addressed. While sharing information, privacy is without any doubt one of the major concerns for all users. Several proposals in the literature treated privacy issues using existing anonymization techniques, but few of them considered accountability service. Whereas, when security systems do not adopt accountability mechanisms, full anonymity may encourage users to act maliciously. In this paper, we propose a novel accountable privacy-preserving solution for public information sharing in data externalization platforms. Based on signatures, our scheme allows externalization servers to authenticate any user in the system without violating its privacy. In case of misbehavior, our solution allows to trace malicious users thanks to an authority. Moreover, our solution ensures privacy-preserving and accountability services in a completely distributed manner, without a permanent resort to the authority. Finally, we show through experimentation that our solution outperforms existing accountable privacy-preserving solutions.