In this research work, we analyze the problem of spectrum trading in virtualized multi-tenant 5G networks using principles from matching theory. More specifically, we deal with the matching problem among the Mobile Network Operators (MNOs) and the Mobile Virtual Network Operators (MVNOs) and we propose a matching scheme that takes into account the preferences of each entity in terms of different utility variables. Our proposal includes a many-to-many matching scheme, that is an extension of the deferred acceptance algorithm, where each MNO and MVNO can cooperate with one or more MVNOs and MNOs, respectively. The performance of our proposed scheme is finally investigated by comparing it with various schemes and some useful conclusions are drawn.

Abstract. The expected huge increase of mobile devices and user data demand by 2020 will stress the current mobile network in an unprecedented way. The future mobile networks must meet several strong requirements regarding the data rate, latency, quality of service and experience, mobility, spectrum and energy efficiency. Therefore, efforts for more efficient mobile network solutions have been recently initiated. To this direction, load balancing has attracted much attention as a promising solution for higher resource utilization, improved system performance and decreased operational cost. It is an effective method for balancing the traffic and alleviating the congestion among heterogeneous networks in the upcoming 5G networks. In this paper, we focus on an offloading scenario for load balancing among LTE and Wi-Fi networks. Additionally, network graphs methodology and its abstracted parameters are investigated in order to better manage wireless resource allocation among multiple connections. The COHERENT architectural framework, which consists of two main control components, makes use of such abstracted network graphs for controlling or managing various tasks such as traffic steering, load balancing, spectrum sharing and RAN sharing. As a result, the COHERENT project eventually develops a unified programmable control framework used to efficiently coordinate the underlying heterogeneous mobile networks as a whole.

The scope of this paper is to present contemporary communication aspects regarding the employment in future of smart grid as a wireless ecosystem. A wide rigorous survey on wireless access and network technologies ideal for smart grid networks is conducted, and we present applicable technologies like Internet of Things (IoT) and Machine-to-Machine (M2M) communications. Moreover, we present key topics of security, privacy and cryptography. Indeed, multimedia services will be provided in a wireless communications environment of a smart grid, while Quality of Service (QoS) as well as security audit shall always be crucial dimensions during a communication network modelling and planning. More specifically, the objective of our work is concentrated on the study of smart grid communications topics and security evaluation using a simulation environment and to demonstrate some interesting results.

Abstract. Global data traffic explosion is expected to set stringent requirements for next generation networks in the next decades. Besides, very low latencies will have to be guaranteed for enabling new delay critical services. However, current Software Defined Networking (SDN) solutions have limitations in terms of separating both data and control planes among tenants/operators, and the capability to adapt to new or changing requirements. Moreover, some virtualization schemes do not ensure isolation of resources and do not guarantee bandwidth across the entities. While some others fail to provide flexibility to the slices to customize the resource allocation across the users. Therefore, novel SDN and virtualization techniques should be implemented to realize the upcoming 5G network that will facilitate at least efficient resource allocation and multi-tenancy among the plethora of different requirements.

This research work describes the role of the Central Controller and Coordinator (C3) entity and its potential techno-economic gain when implemented in the upcoming 5G networks. We investigate how viable could be for a C3 Producer and for a cellular network Operator to produce and implement respectively the C3 entity in its network. The performance of techno-economic analysis is estimated by considering various key parameters and some useful conclusions are drawn.