Device-to-device (D2D) communication is one of the most promising innovations in the next-generation wireless ecosystem, which improves the degrees of spatial reuse and creates novel social opportunities for users in proximity. As standardization behind network-assisted D2D technology takes shape, it becomes clear that security of direct connectivity is one of the key concerns on the way to its ultimate user adoption. This is especially true when a personal user cluster (that is, a smartphone and associated wearable devices) does not have a reliable connection to the cellular infrastructure. In this paper, we propose a novel framework that embraces security of geographically proximate user clusters. More specifically, we employ game-theoretic mechanisms for appropriate user clustering taking into account both spatial and social notions of proximity. Further, our information security procedures implemented on top of this clustering scheme enable continuous support for secure direct communication even in case of unreliable/unavailable cellular connectivity. Explicitly incorporating the effects of user mobility, we numerically evaluate the proposed framework by confirming that it has the potential to substantially improve the resulting system-wide performance.
The expansion of the service scope of cellular networks to include a wide variety of services such as mobile broadband, Internet of Things, and mission-critical machine-type communications has significantly shaped the evolution towards 5G and beyond systems. All these services impose divergent and often mutually exclusive requirements in terms of data rate, latency, and energy efficiency. To satisfy heterogeneous requirements, 5G systems should have properties such as Quality-of-Experience awareness, adaptability and flexibility, scalability and reliability, support for multiple RATs, and backward compatibility, all at a low CAPEX and OPEX. To this end, software-defined networking and network function virtualization have been envisioned as key enabling technologies for 5G, and represent a major paradigm shift for 5G systems. In recent years, a plethora of software-defined mobile network architectures have been introduced worldwide, each with their unique features and drawbacks. Within this context, this paper introduces a new architecture called ARBAT which has been designed to satisfy and exceed the requirements put forth by 5G. ARBAT is characterized by many innovative features such as the Universal Network Device and Unified Cellular Network concepts, multi-slice modular resource management with the AirHYPE wireless hypervisor, network-user application interaction through the xStream platform, and simplified multi-tenant orchestration through ServiceBRIDGE. The novel features of the ARBAT infrastructure plane, data plane, control plane and Management and Orchestration entity are also explained in the paper in detail. Furthermore, a qualitative evaluation and feature comparison of ARBAT with other state-of-the-art architectures is conducted to demonstrate that ARBAT satisfies the aforementioned objectives of the 5G systems.
As mobile communications technology is completing its fifth-generation (5G) cycle, it becomes increasingly capable of supporting novel usage scenarios with stringent performance requirements. Beyond seamless broadband connectivity for humans, 5G systems are preparing to enable a wide range of machine-type applications, thus advancing the vision of the Internet of Things (IoT). Facilitated by the rapidly converging 5G-IoT ecosystem, next-generation industrial IoT services, however, pose unprecedented research problems, primarily along the lines of providing wireless connectivity with ubiquitous availability, extreme reliability, and ultra-low latency. To this end, the first part of this paper presents a concise update on the novel requirements and challenges in the context of the emerging Industrial Internet infrastructure. In the second part, we introduce and solve a new optimization problem formulation aimed at improving performance reliability for advanced IoT devices equipped with several radio access technologies. We argue that by intelligently leveraging such heterogeneous multi-connectivity, future 5Ggrade IoT applications will be able to improve their levels of operational reliability. Our conclusions are corroborated by rigorous mathematical derivations as well as several realistic numerical examples.