A Survey on Socially Aware Device-to-Device Communications

Device-to-device (D2D) communication is continuously evolving and engulfing a wide diversity of proximate services and applications, which is considered as one of the key technologies in the 5G ecosystem. It is argued that direct communications paradigm advantages may not be entirely captured without embracing the concepts of the social-domain. Following the explosion of social networks and smart mobile devices, social-interactions among mobile users enable the promotion of D2D co-operations. In this paper, we first present a systematic overview of the socially unaware technical challenges and the prospective applications to consolidate a background on D2D communications. Next, all the social features utilized in tackling and improving the technical issues and the applications are briefed, respectively. Then, we provide a comprehensive survey on socially aware D2D communications, where various features of social-domain are leveraged, such as ties, community, trust, and selfishness to tackle the D2D technical issues and improve the performance of prospective D2D applications. We categorize state-of-the-art socially aware D2D communications into two main sections. The first section considers technical issues, while the second section pertains to their applications to provide insightful information and motivate more in-depth studies in this area. For each aforementioned section, we overview technical aspects and classify the core contributions based on approaches used and the social features utilized. In the discussion section, we summarize the socially aware D2D communications and present lessons learned. Finally, we highlight the open research challenges in this field and predict future research trends.