Dynamic Social Trust Associations over D2D Communications: An Implementation Perspective

Network-assisted device-to-device (D2D) connectivity is a next-generation wireless technology that facilitates direct user contacts in physical proximity while taking advantage of the flexible and ubiquitous control coming from the cellular infrastructure. This novel type of user interactions creates challenges in constructing meaningful proximity-based applications and services that would enjoy high levels of user adoption. Accordingly, to enable such adoption a comprehensive understanding of user sociality and trust factors is required together with respective technology enablers for secure D2D communications, especially when cellular control is not available at all times. In this paper, we study an important aspect of secure communications over proximity-based direct links, with a primary emphasis on developing the corresponding proof-of-concept implementation. Our developed prototype offers rich functionality for dynamic management of security functions in proximate devices, whenever a new device joins the secure group of users or an existing one leaves it. To evaluate the behavior of our implemented application, we characterize its performance in terms of computation and transmission delays from the user perspective.