Since the conception of the Internet of things (IoT), a large number of promising applications and technologies have been developed, which will change different aspects in our daily life. This paper explores the key characteristics of the forthcoming IEEE 802.11ah specification. This future IEEE 802.11 standard aims to amend the IEEE 802.11 legacy specification to support IoT requirements. We present a thorough evaluation of the foregoing amendment in comparison to the most notable IEEE 802.11 standards. In addition, we expose the capabilities of future IEEE 802.11ah in supporting different IoT applications. Also, we provide a brief overview of the technology contenders that are competing to cover the IoT communications framework. Numerical results are presented showing how the future IEEE 802.11ah specification offers the features required by IoT communications, thus putting forward IEEE 802.11ah as a technology to cater the needs of the Internet of Things paradigm.
Afaqui, M.; Garcia-Villegas, E.; Lopez-Aguilera, E.; Campus, D. IEEE International Conference on Communications p. 1-7 DOI: 10.1109/ICC.2016.7511025 Data de presentació: 2016-05 Presentació treball a congrés
Afaqui, M.; Garcia-Villegas, E.; Lopez-Aguilera, E. IEEE Wireless Communications and Networking Conference p. 1-6 DOI: 10.1109/WCNC.2016.7565005 Data de presentació: 2016-04 Presentació treball a congrés
The need for higher data rates and improved coverage has led to massive and uncoordinated deployments
of IEEE 802.11 based WLAN Access Points in geographically limited areas that has resulted in increased interference
with reduced area throughput. Recently, the IEEE 802.11 working group has continued efforts to cater the
aforementioned problems by creating the IEEE 802.11ax Task Group, TGax (which aims to improve performance in
dense environments). TGax has been actively involved in the design of Clear Channel Access (CCA) modification
schemes, where Dynamic Sensitivity Control (DSC) algorithm has been proposed as one of the key innovative
technologies to increase the spectral reuse. However, DSC scheme has drawbacks: increase in frame collisions as
well as hidden node count. In this paper, we propose the combined usage of DSC along with an intelligent mechanism
to enable RTS/CTS on selected stations within densely deployed WLAN network. We present methods to select
stations for 4-way handshake and indicate considerable gains (up to 60%) when a network utilizing the aforementioned
method is compared with legacy IEEE 802.11 operation.
The vision of future 5G networks encompasses a heterogeneous communication landscape in which existing Radio Access Technologies (RATs) will be integrated with evolving wireless technologies and systems, software-design network architectures and cloud-enabled services. Effectively harnessing the potential of all these innovative and heterogeneous features and providing a programmable multi-tenant network architectural framework will be the key to the success of 5G, and will be the main objective of the 5G-AURA project. Instead of focusing separately on the optimization of the diverse technological and architectural components, our efforts will be concentrated on providing a unifying framework that will sustain the coexistence and coordination of networking, software and cloud technologies, ensure network programmability and efficient resource orchestration, minimize control and signalling overhead, support multi-tenancy and scalability, and promote the development of new business models for emerging services. To efficiently achieve these objectives, 5G-AURA has identified 12 specific research challenges which have been mapped to 14 individual projects that will be carried out by 14 recruited ESRs. The project’s consortium, formed by four academic institutions and four industrial partners, has the necessary expertise and available infrastructures to form a high quality training network across multiple disciplines, sectors and countries. Considering that 5G is currently in an early development state and there are multiple open issues on 5G protocols, network architectures and technologies and standardization efforts, the timing of 5G-AURA is perfect, and the project has a strong potential to have significant impact on academia and industry and enhance the European innovation capacity in terms of technical contributions, intersectoral training of scientists and professional and novel business opportunities.
The proliferation of IEEE 802.11 networks has made them an easy and attractive target for malicious devices/adversaries which intend to misuse the available network. In this paper, we introduce a novel malicious entity detection method for IEEE 802.11 networks. We propose a new metric, the Beacon Access Time (BAT), which is employed in the detection process and inherits its characteristics from the fact that beacon frames are always given preference in IEEE 802.11 networks. An analytical model to define the aforementioned metric is presented and evaluated with experiments and simulations. Furthermore, we evaluate the adversary detection capabilities of our scheme by means of simulations and experiments over a real testbed. The simulation and experimental results indicate consistency and both are found to follow the trends indicated in the analytical model. Measurement results indicate that our scheme is able to correctly detect a malicious entity at a distance of, at least, 120 m. Analytical, simulation and experimental results signify the validity of our scheme and highlight the fact that our scheme is both efficient and successful in detecting an adversary (either a jammer or a cheating device). As a proof of concept, we developed an application that when deployed at the IEEE 802.11 Access Point, is able to effectively detect an adversary. (C) 2015 Elsevier B.V. All rights reserved.
Camps, D.; Garcia-Villegas, E.; Lopez-Aguilera, E.; Loureiro, P.; Lambert, P.; Raissinia, A. IEEE Wireless communications Vol. 22, num. 2, p. 118-125 DOI: 10.1109/MWC.2015.7096294 Data de publicació: 2015-04-01 Article en revista
There is untapped potential in the WiFi radios embedded in our smartphone and tablet devices. In this article we introduce the WiFi Neighbor Awareness Networking technology being standardized in the WiFi Alliance (R), which leverages this potential by allowing handheld devices to continuously discover other interesting services and devices while operating in the background in an energy-efficient way. In addition, we present a thorough performance evaluation based on packet-level simulations that illustrates the performance of WiFi NAN to be expected in realistic scenarios.
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.”
Afaqui, M.; Garcia-Villegas, E.; Lopez-Aguilera, E.; Smith, G.; Camps, D. IEEE Wireless Communications and Networking Conference p. 1060-1065 DOI: 10.1109/WCNC.2015.7127616 Data de presentació: 2015-03-11 Presentació treball a congrés
The explosive growth in the usage of IEEE 802.11 network has resulted in dense deployments in diverse environments. Most recently, the IEEE working group has triggered the IEEE 802.11ax project, which aims to amend the current IEEE 802.11 standard to improve efficiency of dense WLANs. In this paper, we evaluate the Dynamic Sensitivity Control (DSC) Algorithm proposed for IEEE 802.11ax. This algorithm dynamically adjusts the Carrier Sense Threshold (CST) based on the average received signal strength. We show that the aggregate throughput of a dense network utilizing DSC is considerably improved (i.e. up to 20%) when compared with the IEEE 802.11 legacy network.
Today, the vast majority of personal communication devices, such as laptops, smartphones, and logically wireless fidelity (Wi-Fi) access points feature IEEE 802.11 chipsets. In turn, wake-up radio (WuR) systems are used to reduce the significant energy waste that wireless devices cause during their idle communication mode. A novel WuR system is introduced that enables any IEEE 802.11-enabled device to be used as a WuR transmitter without requiring any hardware modification. The corresponding developed WuR receiver achieves a remarkably low power consumption of 10.8 µW and operates in the Wi-Fi 2.4 GHz band. By means of thorough physical tests, it is shown that the proposed IEEE 802.11-based WuR system enables important energy savings.
Wireless Local Area Networks have been increasingly deployed and become very popular. They offer important advantages such as the higher flexibility and user mobility, however, this kind of networks also present some security concerns due to its broadcast nature. Security mechanisms can be classified into two groups: user authentication and data confidentiality.; The IEEE 802.11i specification presents RSNA authentication mechanism, which allows user authentication employing IEEE 802.1x protocol and EAP methods. Authentication mechanisms consist in an important step of the handoff process, which occurs when a mobile node leaves the coverage area of an access point and performs association with another. Handoff results in a critical function for IEEE 802.11 MAC operation due to important delay restrictions. Thus, pre-authentication and IEEE 802.11r mechanisms have been presented to allow important latency reduction, which provide interesting results in real time communications.; Besides, usually, WLAN users employ mobile devices, which provide limited capabilities in terms of energy management.; In this way, in this paper, we evaluate authentication latency and battery consumption by means of an analytical model that we have developed for this purpose. The analysis also includes the influence of transmission errors, which allows the evaluation of authentication mechanisms in error-prone scenarios. (C) 2014 Elsevier B.V. All rights reserved.
Vivimos completamente rodeados por una miríada de dispositivos electrónicos interconectados, que a su vez originan nuevos servicios y nuevas formas de entender y establecer las relaciones sociales. Nuevas palabras y conceptos acompañan inexorablemente dichos avances. Un progreso que, en muchas ocasiones, implica profundas reflexiones y ciertas dosis de incomprensión: ¿Cómo funcionan tales dispositivos? ¿Cómo es posible la conexión con las antípodas de forma tan simple? Este libro pretende dar respuestas a tales cuestiones, utilizando conceptos básicos de las telecomunicaciones y desafiando al lector a afrontar los retos tecnológicos de las comunicaciones.
Garcia-Villegas, E.; Gomez, M.; Lopez-Aguilera, E.; Casademont, J. International Wireless Communications and Mobile Computing Conference p. 57-61 DOI: 10.1145/1815396.1815410 Presentació treball a congrés
IEEE 802.11 Wireless LANs (WLANs) are highly sensitive to Denial of Service (DoS) attacks carried out with jamming devices. In this paper we focus on 2.4GHz wideband constant jammers. The interest in the wideband jammer lies in the fact that it beats all
possible channels at the same time, leaving no possible escape following traditional channel-switching defenses. After studying
and developing an effective detection mechanism, we propose the implementation of a load balancing technique based on cell
breathing for mitigating the harmful effects of the jammer over an IEEE 802.11 WLAN. Cell breathing is achieved by dynamically tuning the transmission power to adjust the size of a WLAN cell.
Lopez-Aguilera, E.; Heusse, M.; Grunenberger, Y.; Rousseau, F.; Duda, A.; Casademont, J. IEEE transactions on mobile computing Vol. 7, num. 10, p. 1213-1227 Data de publicació: 2008-10 Article en revista
Since the advent of the first IEEE 802.11 standard, several papers have proposed means of providing QoS to IEEE 802.11 networks and evaluate various traffic-prioritization mechanisms. Nevertheless, studies on the assignment of AIFS times defined in IEEE 802.11e reveal that the various priority levels work in a synchronized manner. The studies show that, under large loads of high-priority traffic, EDCA starves low-priority frames, which is undesirable. We argue that QoS traffic needs to be prioritized, but users sending best-effort frames should also obtain the expected service. High-priority traffic can also suffer performance degradation when using EDCA because of heavy loads of low-priority frames. Thus, we have proposed a mechanism based on desynchronizing the IEEE 802.11e working procedure. It prevents stations that belong to different priority classes from attempting simultaneous transmission, prioritizes independent collision groups and achieves better short-term and long-term channel access fairness. We have evaluated the proposal based on extensive analytical and simulation results. It prevents the strangulation of low-priority traffic, and, moreover, reduces the degradation of high-priority traffic with the increased presence of low-priority frames.
Lopez-Aguilera, E.; Casademont, J.; Cotrina, J.; Rojas, A. IEEE International Symposium on Personal Indoor and Mobile Radio Communications p. 1463-1467 Data de presentació: 2005-09-01 Presentació treball a congrés
Lopez-Aguilera, E.; Casademont, J.; Rojas, A.; Cotrina, J. The IASTED International Conference on Wireless Networks and Emerging Technologies Data de presentació: 2005-07-01 Presentació treball a congrés
Casademont, J.; Lopez-Aguilera, E.; Paradells, J.; Rojas, A.; Calveras, A.; Barcelo, F.; Cotrina, J. Computers and geosciences Vol. 30, num. 6, p. 671-682 DOI: 10.1016/j.cageo.2004.02.004 Data de publicació: 2004-07 Article en revista
At present, there is a growing interest in wireless applications, due to the fact that the technology begins to support them at reasonable costs. In this paper, we present the technology currently available for use in wireless environments, focusing on Geographic Information Systems. As an example, we present a newly developed platform for the commercialization of advanced geographical information services for use in portable devices. This platform uses available mobile telephone networks and wireless local area networks, but it is completely scalable to new technologies such as third generation mobile networks. Users access the service using a vector map player that runs on a Personal Digital Assistant with wireless access facilities and a Global Positioning System receiver. Before accessing the information, the player will request authorization from the server and download the requested map from it, if necessary. The platform also includes a system for improving Global Positioning System localization with the Real Time Differential Global Positioning System, which uses short GSM messages as the transmission medium.