D2D group communications security

Proximity Services (ProSe) discovery or communications using LTE-based Device-to-Device (D2D) communications have been recently in the heart of the discussions about the advent of 5G networks. Meanwhile, their related security aspects are of a major concern especially when dealing with direct radio communications and large-scale deployment of D2D groups. As the security features of short radio communications are much less robust than those used in public cellular systems, they would not be adequate for major public services and they would be unsuitable for public safety (PS-ProSe) applications proposed by D2D. Yet, existing security algorithms and solutions are not adapted to these emerging new types of communications and group formation. The goal of this paper is focused on D2D communications´ security issues in both ProSe discovery and communication phases. First, we address the global security stakes and challenges in group communications. Then, we propose a Group Key Management (GKM) mechanism to secure the exchanged D2D messages during the discovery and communication phases. The proposed solution is discussed and compared to similar solutions for GKM near to our D2D use cases (i.e. ad-hoc). Moreover, the implemented solution results indicate an efficient key management system for our D2D group communication.