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Verification of theoretical analysis is a vital step in the development of an application or a protocol for wireless networks. Most proposals are evaluated through mathematical analysis followed by either simulation or experimental validation campaigns. In this article, we analyze a large set of statistics in articles published (674 papers in total) in the top representative ad hoc and wireless sensor networks related conferences (i.e., ACM/ IEEE IPSN, ACM MobiCom, ACM MobiHoc, and ACM SenSys) during the period 2008?2013. We focus on the evaluation methodologies provided by researchers. More specifically, our goal is to explore the role of simulators and testbeds in the theoretical analysis of a model throughout the protocol development procedure. We show that there is a tendency for more and more researchers to rely on custom or open testbeds in order to evaluate the performance of their proposals. Simulators indeed fail to reproduce actual environmental conditions of deployed systems. Experimentation with real hardware allows our research community to mind the gaps between simulation and real deployment. Still, as the experimental apFproach through custom testbeds results in a low reproducibility level (i.e., 16.5 percent), we investigate to what extent such performance evaluation methods will be able to bridge those gaps. We finally discuss experimental testbeds and their potential to replace simulators as the cornerstone of performance evaluation procedures. [ABSTRACT FROM PUBLISHER]

This is Part 2 of a Feature Topic (FT) series covering the convergence of communications, caching, and computing for next generation wireless mobile networks. The design and engineering philosophy of modern wireless networks is witnessing a fundamental shift from being "connection-centric" to being "content-centric". This FT aims to provide a comprehensive overview of recent progress in the theoretical foundation, architectural advances, modeling/analytics, protocol engineering, and prototyping of content-centric mobile networks. The response to our Call for Papers was overwhelming, with a total of 54 articles submitted by leading researchers and practitioners from around the world. Following a rigorous review process, Part 1 of this FT series, containing 12 articles, appeared in the August issue of IEEE Communications Magazine. The following additional six papers are selected to be included in Part 2 of the series. [ABSTRACT FROM PUBLISHER]

Research in ad hoc and sensor networks has produced a plethora of papers, and very interesting work is still being published in this area, evolving in parallel with technological innovation, and intersecting with novel areas, particularly the Internet of Things, and more established areas such as wildlife monitoring. [ABSTRACT FROM PUBLISHER]

With ever growing popularity and widespread adoption of mobile social applications, the traffic handled by mobile networks and the Internet has grown significantly. While researchers have been making advances in the study of social networks and independently in the area of next generation wireless networks, very little attention has been given to the interplay between the two, and their impact on each other and society. The challenge of the interplay between social networks and mobile networks is compounded by the fact that advances in smart handheld devices and those in wireless technologies have paved the way for increasing bandwidth catering to very high data rates. Sophisticated social applications such as Second Life, and those involving 3D and real-time data can take advantage of such advances. It is entirely likely that such advances in turn could lead to novel social applications not yet thought of. For example, new social applications could emerge in the area of social health or social games with new forms of massively multi-player, multimedia, 3D, and role playing games. [ABSTRACT FROM PUBLISHER]

The seven papers included in this special section focus on Cognitive radio ad hoc networks (CRAHNS). CRAHNs are equipped with the intrinsic capabilities of cognition and self-organization, providing a flexible spectrum- aware communication paradigm in wireless networks. Since available spectrum mostly manifests as several discontinuous frequency ranges, CRAHNs should be able to operate on multiple frequency channels. Multi-channel CRAHNs can alleviate interference and improve the spectrum utilization with greater fl exibility for channel access. The promising applications of multi-channel CRAHNs include large-scale machine-to-machine (M2M) communication, the Internet of Things (IoTs), high-density Wi-Fi, and unmanned aerial vehicle (UAV) swarms. Multi-channel CRAHNs impose unique challenges due to the distributed dynamic network topology and the temporal or spatial variations in spectrum availability. To overcome these challenges, fundamental problems in multi-channel CRAHNs have to be carefully resolved with respect to spectrum sensing, convention resolution, network topology maintenance, and application support. [ABSTRACT FROM AUTHOR]

Modern tactical operations have complex communication and computing requirements, often involving different coalition teams, that cannot be supported by today's mobile ad hoc networks. To this end, the emerging software defined networking (SDN) paradigm has the potential to enable the redesign and successful deployment of these systems. In this article, we propose a set of novel architecture designs for SDN-enabled mobile ad hoc networks in the tactical field. We discuss in detail the challenges raised by the ad hoc and coalition network environment, and we present specific solutions to address them. The proposed approaches build on evidence from experimental evaluation of such architectures and leverage recent theoretical results from SDN deployments in large backbone networks. [ABSTRACT FROM AUTHOR]

The terahertz band, 0.1-10 THz, has sufficient resources not only to satisfy the 5G requirements of 10 Gb/s peak data rate but to enable a number of tempting rate-greedy applications. However, the terahertz band brings novel challenges, never addressed at lower frequencies. Among others, the scattering of terahertz waves from any object, including walls and furniture, and ultra-wideband highly directional links lead to fundamentally new propagation and interference structures. In this article, we review the recent progress in terahertz propagation modeling, and antenna and testbed designs, and propose a step-by-step roadmap for wireless terahertz Ethernet extension for indoor environments. As a side effect, the described concept provides a second life to the currently underutilized Ethernet infrastructure by using it as a universally available backbone. By applying real terahertz band propagation, reflection, and scattering measurements as well as ray-tracing simulations of a typical office, we analyze two representative scenarios at 300 GHz and 1.25 THz frequencies, illustrating that extremely high rates can be achieved with realistic system parameters at room scales. [ABSTRACT FROM AUTHOR]

We propose a fog-cloud hybrid architecture that can support a massive ad hoc crowd composed of a massive social network and distributed IoT nodes around a smart city environment. The fog computing framework is introduced to support energy efficiency by incorporating IoT nodes that act as an interface to the ad hoc crowd, is aware of user contexts within its vicinity, can do real-time processing of user requests, supports a constrained amount of data offloading, and pass the geo-tagged multimedia data available from the subset of the ad hoc crowd to the big data repository in the cloud. The framework leverages a sustainable crowdsourcing incentive model for both the ad hoc crowd and the IoT infrastructure provider. The proposed sustainable framework can potentially support context-aware smart city services such as finding a lost person within the crowd, showing green and health risk prone zones, semantic and location-aware notifications of events of interest, semantic IoT-based routing, and dealing with emergency situations. We present a communication architecture between mobile users and fog nodes, and between fog nodes and the cloud, a sustainability and energy efficiency model, and massive geo-tagged, multimedia big data architecture. [ABSTRACT FROM PUBLISHER]

The increasing popularity of wireless services and devices necessitates high bandwidth requirements; however, spectrum resources are not only limited but also heavily underutilized. Multiple license channels that support the same levels of QoS are desirable to resolve the problems posed by the scarcity and inefficient use of spectrum resources in multi-channel cognitive radio networks (MCRNs). One reason is that multimedia services and applications have distinct, stringent QoS requirements. However, due to a lack of coordination between primary and secondary users, identifying the QoS levels supported over available licensed channels has proven to be problematic and has yet to be attempted. This article presents a novel Bayesian non-parametric channel clustering scheme, which identifies the QoS levels supported over available license channels. The proposed scheme employs the infinite Gaussian mixture model and collapsed Gibbs sampler to identify the QoS levels from the feature space of the bit rate, packet delivery ratio, and packet delay variation of licensed channels. Moreover, the real measurements of wireless data traces and comparisons with baseline clustering schemes are used to evaluate the performance of the proposed scheme. [ABSTRACT FROM AUTHOR]

In this article, the channel hopping (CH) method for the rendezvous process of secondary users in multi-channel CRAHNs is overviewed. With the evolution of the Internet of Things, design criteria of CH sequences targeting these applications are discussed. While channel collision among CH sequences is inherent in realistic CRAHNs, most prior works focused on sequence designs without addressing the channel collision problem. Hence, the concept of contention resolution in CRAHNs is introduced in this article, and a "multi-round" contention resolution mechanism is studied. To quantify the performance, the RS rate of the mechanism is presented and validated with computer simulation. Finally, the rendezvous time savings, which, in turn, can enhance data throughput, of the multi-round mechanism over a single-round one are investigated. [ABSTRACT FROM AUTHOR]

Ad hoc networks rely on the mutual cooperation of stations. As such, they are susceptible to selfish attacks that abuse network mechanisms. Class-based QoS provisioning mechanisms, such as the EDCA function of IEEE 802.11, are particularly prone to traffic remapping attacks, which may bring an attacker better QoS without exposing it to easy detection. Such attacks have been studied in wireless LANs, whereas their impact in multihop settings is less known. We provide a definition of traffic remapping attacks, highlighting their ease of execution, and analyze their impact in multihop networks. Suitable detection methods and defense measures are also discussed and evaluated. [ABSTRACT FROM AUTHOR]

This article addresses one of the key challenges of engaging a massive ad hoc crowd by providing sustainable incentives. The incentive model is based on a context-aware cyber-physical spatio-temporal serious game with the help of a mobile crowd sensing mechanism. To this end, this article describes a framework that can create an ad hoc social network of millions of people and provide context-aware serious-game services as an incentive. While interacting with different services, the massive crowd shares a rich trail of geo-tagged multimedia data, which acts as a crowdsourcing eco-system. The incentive model has been tested on the mass crowd at the Hajj since 2014. From our observations, we conclude that the framework provides a sustainable incentive mechanism that can solve many real-life problems such as reaching a person in a crowd within the shortest possible time, isolating significant events, finding lost individuals, handling emergency situations, helping pilgrims to perform ritual events based on location and time, and sharing geo-tagged multimedia resources among a community of interest within the crowd. The framework allows an ad hoc social network to be formed within a very large crowd, a community of interests to be created for each person, and information to be shared with the right community of interests. We present the communication paradigm of the framework, the serious game incentive model, and cloud-based massive geo-tagged social network architecture. [ABSTRACT FROM PUBLISHER]

Mobile crowdsensing (MCS) enables collective data harvesting actions by coordinating citizens willing to contribute data collected via their sensor-rich smartphones that represent sources of valuable sensing information in urban environments nowadays. One of the biggest challenges in a real long-running MCS system lies in the capacity not only to attract new volunteers, but also, and most importantly, to leverage existing social ties between volunteers to keep them involved to build long-lasting MCS communities. In addition, the advent of high-performing devices and ad hoc communication technologies can help to further amplify the effect of sensing actions in proximity of the volunteer devices. This article originally describes how to exploit these socio-technical networking aspects to increase the performance of MCS campaigns in the ParticipAct living laboratory, an ongoing MCS real-world experiment that involved about 170 students of the University of Bologna for more than two years. The article also reports some significant experimental results to quantify the effectiveness of the proposed techniques. [ABSTRACT FROM PUBLISHER]

Since 2012, 3GPP Release 12 (the beyond fourth generation (B4G) network) has been adopted as the next generation public safety network to be deployed in 2015. In addition to conventional high data rate transmissions in LTE-A, a public safety network is required to further support communications for users out of base station (BS) coverage. Avoiding any signal relay via BSs, direct data exchanges among users, known as deviceto- device (D2D) communications, have consequently emerged as the most crucial innovation and the mandatory technology for a public safety network. However, due to the tight schedule for standardization, a special form of "broadcasting" communications has been adopted by D2D communications in Release 12. To fully comprehend such an unprecedented technology in cellular networks, this article provides a comprehensive overview of D2D operations in Release 12. From the system architecture to the radio interface, the provided insights boost the knowledge to practice D2D communications over cellular networks. [ABSTRACT FROM AUTHOR]

The influence of social interactions among mobile devices and network components in wireless networks has attracted substantial attention due to its potential impact on resource allocation of spectrum and power in particular. We present an organized social graphical view on resource allocation and then extend to multi-objective resource allocation of wireless networks. We subsequently consider taking advantage of multi-dimensional resources, including radio resource, user behavior, and content characteristics, such that we can successfully integrate caching capability, interest similarity, and content popularity and distribution into wireless network design. As an illustration, device-to-device communications is utilized to form pairs and clusters of mobile devices regarding optimal resource matching via a bipartite graph. This socially enabled methodology highlights new potential to design wireless networks and 5G mobile communications. [ABSTRACT FROM PUBLISHER]

Cellular networks are confronted with unprecedented pressure to accommodate the dramatically increasing demands of mobile Internet. This phenomenon is principally due to the restricted spectrum resource and low-efficiency spectrum management. Recently, cognitive radio technology has been corroborated to significantly improve spectrum utilization efficiency. In order to enhance the spectrum management efficiency in cellular networks, the concept of ?cognitive cellular networks? was introduced. It has been realized that the network architecture, algorithms, and protocols cannot be simply designed without considering the socio-economic aspects involved. In this article, we consider the economic issues in cognitive cellular networks from the perspectives of game theoretic modeling and mechanism design. Specifically, both the simultaneous and sequential dynamic spectrum access games are investigated, respectively. The mechanism design related issues (i.e., spectrum auction, pricing, and contract) to ensure desired outcomes are introduced with detailed applications in cognitive cellular networks. The goal of this article is to provide an overview to understand the motivation, problem formulation, methodology, and solutions of the economic issues in cognitive cellular networks. [ABSTRACT FROM PUBLISHER]

In this article we focus on a special case of user-centric networks, spontaneous smartvphone-based networks, SSNs, where the role of the end-user devices is played by smartphones that are "evolutionary" and more active in supporting communication services. SSNs present key features like spontaneity in the creation of the network and redefinition of the devices? role in order to make them continuously adaptive to both network and user requirements. This work is devoted to identifying the potential advantages of SSNs by also providing a clear definition of the challenges and issues that need to be faced in order to make this emerging paradigm effective and practically deployable. [ABSTRACT FROM PUBLISHER]

An introduction is presented in which the editors discuss wireless bandwidth resources in mobile crowdsensing, incentive mechanisms including auctions, lotteries and trust; and game services.

Presents the President's message for this issue of the publication. [ABSTRACT FROM PUBLISHER]

Recent advances in mobile and wireless technology have affected many areas of our lives, including the way we communicate, and how we interact and collaborate. Along with this, we have also witnessed a rapid increase in the mobility of people, thanks to faster transportation methods, simplified connections, and shorter commute times. These developments mean that studying the technological impact of mobile ad hoc and sensor networking now also requires studying aspects of social and human mobility. Mobile and wireless networking now involves people with networked sensors, mobile devices, and sensing context. The performance of each system then also depends on how people interact with these systems. [ABSTRACT FROM PUBLISHER]

Provides a notice of upcoming conference events of interest to practitioners and researchers. [ABSTRACT FROM PUBLISHER]

Iser-centric networks (UCNs) can be seen as a recent architectural trend of self-organizing autonomic networks where the Internet end user cooperates by sharing network services and resources. UCNs are characterized by spontaneous and grassroots deployments of wireless architectures, where users on such environments roam frequently and are also owners of networking equipment. Common to UCNs is a social behavior that heavily impacts network operation from an end-to-end perspective. [ABSTRACT FROM PUBLISHER]