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In the Internet of Things (IoT) context, the massive proliferation of wireless devices implies dense networks that require cooperation for the multihop transmission of the sensor data to central units. The altruistic user behavior and the isolation of malicious users are fundamental requirements for the proper operation of any cooperative network. However, the introduction of new communication techniques that improve the cooperative performance (e.g., network coding) hinders the application of traditional schemes on malicious users detection, which are mainly based on packet overhearing. In this paper, we introduce a non-parametric statistical approach, based on the Kruskal-Wallis method, for the detection of user misbehavior in network coding scenarios. The proposed method is shown to effectively handle attacks in the network, even when malicious users adopt a smart probabilistic misbehavior. ; Grant numbers : This work has been supported by the research projects CellFive (TEC2014-60130-P) and AGAUR the Catalan Government (2014-SGR-1551).© 2016 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.

The present paper studies fair sharing possibilities of stored renewable energy (RE) in densely populated areas among multiple mobile network operators (MNOs). The main objective is to enable MNOs, who already share their infrastructure in terms of a green network operation, to further reduce their power consumption by fairly sharing (i) the solar power harvested during daylight and (ii) the harvested energy that is stored in storage devices, e.g. batteries, during night hours. To this end, a bankruptcy game is designed so as to capture the energy sharing interactions among MNOs. Taking into consideration the energy deficits of each MNO for a studied period of time, Shapley Value (SV) is employed to fairly determine the amounts of energy to be allocated to each MNO. Focusing on night hours, it is shown that the proposed scheme provides all cooperative MNOs with long store-energy-based network operation during night in comparison to baseline schemes. Moreover, we display that the proposed scheme outperforms its counterparts in terms of needed grid support and allocation fairness among the cooperative MNOs for different MNO traffic patterns and volumes. ; Grant numbers : This work was supported by the Catalan Government (2014-SGR-1551), and CellFive (TEC2014-60130-P).© 2017 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.

The anticipated explosion in the total data traffic load will impose to mobile network operators (MNOs) the necessity to densify their networks to provide coverage. At the same time, since MNOs plan their networks according to their high-peak traffic load, base station (BS) underutilization during the low traffic hours raises the issue of unnecessary power consumption and excessive cost. In this paper, we plan to study the energy and cost efficiency of a heterogeneous network (HetNet) that is a cooperation result of many MNOs. Each MNO is owner of a HetNet, composed of eNodeBs and small cells and they cooperate by sharing their infrastructure and by switching off a part of it. BS type and traffic load constitute switching off criteria and a roaming-cost-based user association scheme is used to roam traffic to neighboring BSs. We assess the cost alterations created by the possible MNO coalitions and we propose a bankruptcy game to allocate the obtained cost to the cooperative MNOs and to motivate them thus to maintain their sharing agreement instead of following a non-cooperative tactic. The bankruptcy game uses Shapley Value to portray each MNO's contribution to cost savings. The MNOs' satisfaction from their payoffs (i.e., the allocated cost) and the overall fairness of the method are evaluated. According to the extracted results, the proposed switching off scheme achieves significant improvement of energy efficiency for the studied network, while the proposed bankruptcy game achieves a balanced and satisfactory cost allocation for different MNO traffic loads. ; Grant numbers : This work has been funded by the Catalan Government (2014-SGR-1551), CellFive (TEC2014-60130-P).© 2017 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted ...

The fifth generation wireless networks are expected to offer high capacity and accommodate numerous over-the-top applications, relying on users' Internet connectivity, thus involving different stakeholders, that is, network service providers and over-the-top service providers. For the efficient management of over-the-top application flows, the implementation of service functions and their interconnection in service chains, namely network service chaining, should consider the over-the-top service providers' performance goals and user management strategies. However, in current wireless network deployments, the network service providers have full control of network service chaining. Considering that user satisfaction from the offered services is a common interest for both types of stakeholders, the over-the-top service providers need to participate in network service chaining, and apply QoS and user prioritization policies to network service chain resource management, which involves users connected at different network points, in a distributed manner. In this article, we describe 5G network management architectures and propose virtualization components that enable over-the-top service-provider- oriented network service. We also outline the arising issues for over-the-top service providers in network service chaining and introduce a distributed prioritization network service chain management scheme for over-the-top application flows, based on matching theory. The evaluation results indicate the performance gains in over-the-top service providers' service levels that stem from the proposed scheme, demonstrating the benefits of introducing prioritization in network service chain deployment. ; Grant numbers : This work has been funded by the Catalan Government (2014-SGR-1551), CellFive (TEC2014-60130-P).© 2017 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or ...

The reduction of energy consumption and the people's well-being, in smart buildings, rely on an accurate monitoring of the air quality. Thereby, herein an experimental platform is proposed to achieve this aim, which is inspired on an Internet of Things paradigm. The proposed approach is characterized by its scalability and its energy efficiency. Moreover, it is an end-to-end platform, as it permits to take measurements of the air quality, to store and process the information in a fusion center and to display in real-time the air quality in the Internet users' devices. ; Grant numbers : This work has been partially supported by the Generalitat de Catalunya (2014 SGR 1551) and the Spanish Government under project CellFive (TEC2014-60130-P).© 2017 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.

The latest impressive technological advancements in the telecommunications domain have entailed the involvement of new network operators and over-the-top (OTT) providers that offer their services over the existing networks. This entry of new stakeholders has changed the Internet dynamics and triggered a long-standing conversation on whether different types of data in the network should be prioritized, also known as the network neutrality debate. On the one hand, OTT providers benefit from the current neutral Internet policy of not discriminating against any application or content in order to transfer their data for free, whereas network providers would like to seize the business opportunity and create revenues by supporting the prioritized delivery of data. In this article, we want to shed light on the emerging Internet ecosystem and the conflicting interests of its stakeholders. To that end, we first identify the different Internet players and describe their interrelationships. Furthermore, in an effort to offer a new perspective on the network neutrality debate, we propose two novel econometric models that employ recent financial data to capture the relationship between the OTT revenues and the financial gains and investments of the telecommunication operators. Our empirical results provide tangible answers to fundamental questions that had not been answered before, showcasing that OTT and telecommunication providers have aligned interests and their collaboration could be beneficial to both parties. ; Grant numbers : This work has been supported by the Catalan Government (2014-SGR-1551) and CellFive (TEC2014-60130-P).© 2017 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.

Wireless network virtualization enables efficient network sharing in Long Term Evolution Advanced (LTE-A) networks. For the accommodation of ever-increasing user demands, Mobile Virtual Network Operators (MVNOs) can lease and operate virtual resources in network infrastructure that belongs to Mobile Network Operators (MNOs). The coexistence of multiple MVNOs that serve users with different Quality of Service (QoS) requirements and spatial distribution in an LTE-A cell further complicates the arising resource allocation problem. Moreover, the MVNOs aim to satisfy the QoS demands for the maximum possible number of users with the minimum possible cost. This multifaceted context renders centralized optimization approaches for virtual resource allocation in shared LTE-A networks unsuitable. As an alternative, the framework of matching theory, thanks to its distributed nature, can achieve a proper allocation through a stable matching between resources and MVNOs. In this context, we introduce a matching-theoretic formulation for the virtual resource allocation problem and propose a distributed algorithm that properly matches the MVNOs with the available resources. Our simulation results show that the proposed algorithm reaches a stable matching that satisfies the QoS demands for more users in comparison with other approaches. ; Grant numbers : This work has been funded by the Research Project CellFive (TEC2014-60130-P), AGAUR the Catalan Government (2014-SGR-1551).© 2016 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.

Smart Grid (SG) is considered as the future of the electrical power distribution system, where Advanced Metering Infrastructure (AMI) will let utilities to acquire and analyze the consumption data and access and control several home appliances for power balancing purposes through special devices, known as Smart Meters (SMs). Long Term Evolution (LTE) appears as a promising solution to handle the SMs traffic due to its high bandwidth and flexibility. However, given that SMs need to periodically send measurements to the eNodeB (eNB), the network uplink could be a potential bottleneck, thus affecting the users running real-time applications, such as voice calls. To overcome this problem, in this paper, we present a scheduling policy that jointly considers the channel quality, the traffic prioritization and the AMI Packet Delay Budget (PDB) in order to provide the SMs with the required resources and reduce the impact on the real-time traffic. Extensive simulation experiments have been carried out, indicating the smooth coexistence between the SMs and the voice users, since the proposed scheduler achieves higher percentage of served users compared to widely employed schedulers. ; Grant number : This work has been partially supported by the Catalan Government 2014-SGR-1551.© 2015 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.

In this paper, we propose a novel policy for device caching that facilitates popular content exchange through high-rate device-to-device (D2D) millimeter-wave (mmWave) communication. The D2D-aware caching policy splits the cacheable content into two content groups and distributes it randomly to the user equipment devices, with the goal to enable D2D connections. By exploiting the high bandwidth availability and directionality of mmWaves, we ensure high rates for the D2D transmissions, while mitigating the co-channel interference that limits the throughput gains of the D2D communication in the sub-6-GHz bands. Furthermore, based on a stochastic-geometry modeling of the network topology, we analytically derive the offloading gain that is achieved by the proposed policy and the distribution of the content retrieval delay considering both half- and full-duplex modes for the D2D communication. The accuracy of the proposed analytical framework is validated through Monte Carlo simulations. In addition, for a wide range of a content popularity indicator, the results show that the proposed policy achieves higher offloading and lower content-retrieval delays than existing state-of-the-art approaches. ; Grant numbers : This work has been funded by the Catalan Government (2014-SGR-1551), CellFive (TEC2014-60130-P).© 2017 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.

The emerging traffic demand has triggered an impressive deployment of network infrastructure, including macro Base Stations (BSs) and Small Cells (SCs), leading to increased energy consumption and expenditures. However, the network underutilization during low traffic periods (e.g., night zone) enables the Mobile Network Operators (MNOs) to save energy by having their traffic served by third-party SCs, thus being able to switch off their BSs. In this paper, we propose a novel market approach to foster the opportunistic utilization of unexploited SCs capacity, where the MNOs lease the resources of third-party SCs and deactivate their BSs. Motivated by the conflicting interests of the MNOs and the restricted capacity of the SCs that is not adequate to carry the whole traffic in multi-operator scenarios, we introduce a combinatorial auction framework, which includes: i) a bidding strategy, ii) a resource allocation scheme, and iii) a pricing rule. We propose a multiobjective framework to provide an energy efficient solution for the resource allocation problem and we provide extensive analytical and experimental results to estimate the potential energy savings. ; Grant numbers : This work has been funded by the Research Projects AGAUR the Catalan Government 2014-SGR-1551 (2014-SGR-1551) and Cell-Five (TEC2014-60130-P).© 2016 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.

The emerging data traffic demand has caused a massive deployment of network infrastructure, including Base Stations (BSs) and Small Cells (SCs), leading to increased energy consumption and expenditures. However, the network underutilization during low traffic periods enables the Mobile Network Operators (MNOs) to save energy by having their traffic served by third party SCs, thus being able to switch off their BSs. In this paper, we propose a novel market approach to foster the opportunistic utilization of the unexploited SCs capacity, where the MNOs, instead of requesting the maximum capacity to meet their highest traffic expectations, offer a set of bids requesting different resources from the third party SCs at lower costs. Motivated by the conflicting financial interests of the MNOs and the third party, the restricted capacity of the SCs that is not adequate to carry the whole traffic in multi-operator scenarios, and the necessity for energy efficient solutions, we introduce a combinatorial auction framework, which includes i) a bidding strategy, ii) a resource allocation scheme, and iii) a pricing rule. We propose a multiobjective framework as an energy and cost efficient solution for the resource allocation problem, and we provide extensive analytical and experimental results to estimate the potential energy and cost savings that can be achieved. In addition, we investigate the conditions under which the MNOs and the third party companies should take part in the proposed auction. ; Grant numbers : This work was supported in part by the Research Projects AGAUR the Catalan Government (2014-SGR-1551) CellFive (TEC2014-60130-P).© 2016 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.

The introduction of fourth-generation wireless technologies has fueled the rapid development of cellular networks, significantly increasing the energy consumption and the expenditures of mobile network operators (MNOs). In addition, network underutilization during low-traffic periods (e.g., night zone) has motivated a new business model, namely, infrastructure sharing, which allows the MNOs to have their traffic served by other MNOs in the same geographic area, thus enabling them to switch off part of their network. In this paper, we propose a novel infrastructure-sharing algorithm for multioperator environments, which enables the deactivation of underutilized base stations during low-traffic periods. Motivated by the conflicting interests of the MNOs and the necessity for effective solutions, we introduce a game-theoretic framework that enables the MNOs to individually estimate the switching-off probabilities that reduce their expected financial cost. Our approach reaches dominant strategy equilibrium, which is the strategy that minimizes the cost of each player. Finally, we provide extensive analytical and experimental results to estimate the potential energy and cost savings that can be achieved in multioperator environments, incentivizing the MNOs to apply the proposed scheme. ; Grant numbers : This work has been partially funded by AGAUR the Catalan Government (2014 SGR 1551) and the Research Projects CellFive (TEC2014-60130-P).© 2016 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.

Full-Duplex (FD) wireless and Device-to-Device (D2D) communication are two promising technologies that aspire to enhance the spectrum and energy efficiency of wireless networks, thus fulfilling key requirements of the 5th generation (5G) of mobile networks. Both technologies, however, generate excessive interference, which, if not managed effectively, threatens to compromise system performance. To this direction, we propose two transmission policies that enhance the communication of two interfering FD-enabled D2D pairs, derived from game theory and optimization theory. The game-theoretic policy allows the pairs to choose their transmission modes independently and the optimal policy to maximize their throughput, achieving significant gains when the pairs interfere strongly with each other. ; Grant numbers : This work has been funded by the Research Projects AGAUR the Catalan Government 2014-SGR-1551, CellFive (TEC2014-60130-P).

Target detection wireless sensor networks (WSNs), where binary decisions are transmitted to declare the presence or absence of a given target, are expected to have a fundamental role in the Internet of Things era. However, their simplicity makes these networks very susceptible to malicious attacks, while the problem is aggravated in the presence of intelligent malicious nodes that adapt their strategy depending on the behavior of other nodes in the network. In this paper, first, we analytically demonstrate that dependent and independent malicious nodes have the same impact on the overall performance of target detection WSNs in terms of detection and false alarm rates. Then, taking into account that dependent malicious users cannot be detected by conventional algorithms, we introduce an effective algorithm that detects malicious nodes in the network regardless of their type and number. Finally, theoretical and simulation results are provided to show the effects of dependent malicious nodes and analyze the performance of the proposed algorithm compared with the existing state-of-the-art works. ; Grant numbers : This work is funded by CellFive (TEC2014-60130-P) and by the Catalan Government 2014-SGR-1551.© 2016 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.

Harvesting energy in the human environment has been identified as an effective way to charge the body sensor nodes in wireless body area networks (WBANs). In such networks, the capability of the nodes to detect events is of vital importance and complements the stringent quality of service (QoS) demands in terms of delay, throughput, and packet loss. However, the scarce energy collected by human motions, along with the strict requirements of vital health signals in terms of QoS, raises important challenges for WBANs and stresses the need for new integrated QoS-aware energy management schemes. In this paper, we propose a joint power-QoS (PEH-QoS) control scheme, composed of three modules that interact in order to make optimal use of energy and achieve the best possible QoS. The proposed scheme ensures that a sensor node is able to detect the medical events and transmit the respective data packets efficiently. Extensive simulations, conducted for different human activities (i.e., relaxing, walking, running, and cycling), have shown that the application of PEH-QoS in a medical node increases the detection efficiency, the throughput, and the energy efficiency of the system. ; Grant numbers : This work has been partially funded by the Research Projects AGAUR the Catalan Government 2014-SGR-1551.© 2016 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.