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In recent years, the amount of traffic requests that Internet users generate on a daily basis has increased exponentially, mostly due to the worldwide success of video streaming services, such as Netflix and YouTube. While Content-Delivery Networks (CDNs) are the de-facto standard used nowadays to serve the ever increasing users' demands, the scientific community has formulated proposals known under the name of Content-Centric Networks (CCN) to change the network protocol stack in order to turn the network into a content distribution infrastructure. In this context this Ph.D. thesis studies efficient techniques to foster content distribution taking into account three complementary problems:1) We consider the scenario of a wireless heterogeneous network, and we formulate a novel mechanism to motivate wireless access point owners to lease their unexploited bandwidth and cache storage, in exchange for an economic incentive.2) We study the centralized network planning problem and (I) we analyze the migration to CCN; (II) we compare the performance bounds for a CDN with those of a CCN, and (III) we take into account a virtualized CDN and study the stochastic planning problem for one such architecture.3) We investigate the security properties on access control and trackability and formulate ConfTrack-CCN: a CCN extension to enforce confidentiality, trackability and access policy evolution in the presence of distributed caches. ; Au cours de ces dernières années, la quantité de trafic que les utilisateurs Internet produisent sur une base quotidienne a augmenté de façon exponentielle, principalement en raison du succès des services de streaming vidéo, tels que Netflix et YouTube. Alors que les réseaux de diffusion de contenu (Content-Delivery Networks, CDN) sont la technique standard utilisée actuellement pour servir les demandes des utilisateurs, la communauté scientifique a formulé des propositions connues sous le nom de Content-Centric Networks (CCN) pour changer la pile de protocoles réseau afin de transformer Internet en une infrastructure de distribution de contenu. Dans ce contexte, cette thèse de doctorat étudie des techniques efficaces pour la distribution de contenu numérique en tenant compte de trois problèmes complémentaires : 1) Nous considérons le scénario d'un réseau hétérogène sans fil, et nous formulons un mécanisme pour motiver les propriétaires des points d'accès à partager leur capacité WiFi et stockage cache inutilisés, en échange d'une contribution économique.2) Nous étudions le problème centralisé de planification du réseau en présence de caches distribuées et (I) nous analysons la migration optimale du réseau à CCN; (II) nous comparons les bornes de performance d'un réseau CDN avec ceux d'un CCN, et (III) nous considérons un réseau CDN virtualisé et étudions le problème stochastique de planification d'une telle infrastructure.3) Nous considérons les implications de sécurité sur le contrôle d'accès et la traçabilité, et nous formulons ConfTrack-CCN, une extension deCCN utilisée pour garantir la confidentialité, traçabilité et l'évolution de la politique d'accès, en présence de caches distribuées.

Water quality has an impact on the fishing and aquaculture industry of a community. Tubay Bay is one of the main sources of coastal products of nearby cities like Butuan and Cabadbaran and also serves as the navigation routes of hauling ships of mining companies. Of the Water Quality Index (WQI), the Environmental Management Bureau (EMB) water quality data shows that the pH levels exceeded the limit. This paper presents the initial outputs in the development of a low-cost wireless sensor network (WSN) system using open-source hardware platforms to monitor the pH of the water bodies at Tubay, Agusan del Norte, Philippines. The proposed system is devised to be highly scalable in terms of the type of sensors, the number of sensor nodes, and the technology applied for each node. This is well suited for a wider coverage of monitoring the WQIs of Tubay Bay. Results of this study showed a good transmission performance of real-time water quality data in any areas where GSM signal is present. The established platform and database of this study could provide valuable information that could support or contradict claims by the local government units (LGUs) on the effects of mining activities to the agro-fishing activities in the area and provide insights on which water quality parameters or water condition that are highly correlated to pH must be closely monitored. This demonstrates the use of WSN in establishing a low cost but effective monitoring tool that can be replicated in other areas that need extensive monitoring.

Cover -- Content -- Introduction -- Tech Barons Dream of a Better World - Without the Rest of Us -- Digital Sovereignty -- Algorithmic Sovereignty beyond the Leviathan and the Wicker Man -- Out of Balance. The Impact of Digitalization on Social Cohesion -- Digital Capitalism's Crises of Sovereign -- Agency for All, Privacy for None -- The State. A Key Actor in Shaping Data Infrastructure Space -- At the End of the World, Plant a Tree. Considerations for the End of Human Time -- Building Collective Sovereignty -- Sovereign Imaginaries. How Corporate Digital Imaginaries are endangering our Political Practices -- Geofilters. Vertical Sight and the Tropikós Turn -- Postdigital -- Talk to Me. A Multilingual Installation as a boundary Object for Inclusion in Digital and Public Participation -- Why Feminist Digital Policy Matters -- Researchers Gone Wild. Origins and Endpoints of Image Training Datasets Created "In the Wild" -- Digital Sovereignty in the Pandemic City -- WannaScry! An Interview with Danja Vasiliev -- Digitalization of Art Exhibitions in Times of COVID-19 . Three case studies in China -- a.username? - A Profile Without Qualities. Exploring Amazon through Art and Literature -- Prototyping Digital Sovereignty. Experimenting with Community Wireless Networking Technology -- Viruses as Phenomena of De Facto Destabilization and Potential Subversion -- Authors and Editors.

AbstractBackgroundReal-life community mobility (CM) measures for older adults, especially those with Parkinson's disease (PD), are important tools when helping individuals maintain optimal function and quality of life. This is one of the first studies to compare an objective global positioning system (GPS) sensor and subjective self-report CM measures in an older clinical population.MethodsOver 14 days, 54 people in Ontario, Canada with early to mid-stage PD (mean age = 67.5 ± 6.3 years; 47 men; 46 retired) wore a wireless inertial measurement unit with GPS (WIMU-GPS), and completed the Life Space Assessment and mobility diaries. We assessed the convergent validity, reliability and agreement on mobility outcomes using Spearman's correlation, intraclass correlation coefficient, and Bland-Altman analyses, respectively.ResultsConvergent validity was attained by the WIMU-GPS for trip frequency (rs = .69, 95% confidence interval [CI] = 0.52–0.81) and duration outside (rs = .43, 95% CI = 0.18–0.62), but not for life space size (rs = .39, 95% CI = 0.14–0.60). The Life Space Assessment exhibited floor and ceiling effects. Moderate agreements were observed between WIMU-GPS and diary for trip frequency and duration (intraclass correlation coefficients = 0.71, 95% CI = 0.51–0.82; 0.67, 95% CI = 0.42–0.82, respectively). Disagreement was more common among nonretired individuals.ConclusionsWIMU-GPS could replace diaries for trip frequency and duration assessments in older adults with PD. Both assessments are best used for retired persons. However, the Life Space Assessment may not reflect actual mobility.

"This book focuses on the creation of Sliding Mode Technique & Technology (SM T&T) based on some fundamental advantages of Sliding Mode in the Internet for increasing efficiency of managing and controlling processes in non-engineering systems. It explores topics such as discontinuous control & setting adjustment and the global digital community"--

How hacking cultures drive contemporary capitalism and the future of innovation. In Resistance to the Current, Johan Söderberg and Maxigas examine four historical case studies of hacker movements and their roles in shaping the twenty-first-century's network society. Based on decades of field work and analysis, this intervention into current debates situates an exploding variety of hacking practices within the contradictions of capitalism. Depoliticized accounts of computing cultures and collaborative production miss their core driver, write Söderberg and Maxigas: the articulation of critique and its recuperation into innovations. Drawing on accounts of building, developing, and running community wireless networks, 3D printers, hackerspaces, and chat protocols, the authors develop a theoretical framework of critique and recuperation to examine how hackers—who have long held a reputation for being underground rebels—transform their outputs from communal, underground experiments to commercial products that benefit the state and capital. This framework allows a dialectical understanding of contemporary social conflicts around technology and innovation. Hackers' critiques of contemporary norms spur innovation, while recuperation turns these innovations into commodified products and services. Recuperation threatens the autonomy of hacker collectives, harnessing their outputs for the benefit of a capitalist system. With significant practical implications, this sophisticated multidisciplinary account of technology-oriented movements that seek to challenge capitalism will appeal to science and technology readers interested in innovation studies, user studies, cultural studies, and media and communications.

The network topology used in the Rumbuk village office is a star topology, where every PC / computer in each room is connected using a UTP cable. While all mobile phones are connected wirelessly (without cable) through the access point on the modem. The problem with this network infrastructure is in managing hotspots, monitoring, and network security. From these problems, the author recommends developing by implementing a proxy in building network infrastructure at the Rumbuk village office in the Sakra sub-district. The purpose of this research is to assist the village government in managing the network by monitoring, managing bandwidth, and improving the network security system using a proxy. So that the village government can improve services for the community in the field of information technology optimally. The development of network topology and hotspots is needed to make it easy for village governments to access networks, not only wired networks but also wireless networks. By implementing proxy in this network infrastructure to control all equipment and network users who are allowed to enter or not. Bandwidth settings for all network users are tailored to their individual needs. And the security system contained in the proxy is safe enough because the proxy can limit the access rights of every user who enters the network.DOI : 10.29408/jit.v3i2.2350 ; The network topology used in the Rumbuk village office is a star topology, where every PC / computer in each room is connected using a UTP cable. While all mobile phones are connected wirelessly (without cable) through the access point on the modem. The problem with this network infrastructure is in managing hotspots, monitoring, and network security. From these problems, the author recommends developing by implementing a proxy in building network infrastructure at the Rumbuk village office in the Sakra sub-district. The purpose of this research is to assist the village government in managing the network by monitoring, managing bandwidth, and improving the network security system using a proxy. So that the village government can improve services for the community in the field of information technology optimally. The development of network topology and hotspots is needed to make it easy for village governments to access networks, not only wired networks but also wireless networks. By implementing proxy in this network infrastructure to control all equipment and network users who are allowed to enter or not. Bandwidth settings for all network users are tailored to their individual needs. And the security system contained in the proxy is safe enough because the proxy can limit the access rights of every user who enters the network.

The future of military wireless networks is changing dramatically along with the commercial wireless communication systems. During the last few years, the mobile wireless industry is spending considerable effort to enhance the technical characteristics of existing second generation systems in the goal of upgrading their service provision capabilities and of promoting effective integration with data transport networks (such as GPRS and UMTS). After giving an overview of GPRS and UMTS technologies, the paper proceed to present a set of generic GPRS and UMTS - based architectures, which can be used as migration steps toward third-generation tactical military networks.

Wireless Body Area Networks (WBANs) have increased the attention of the research community for the next generation wireless medical devices. Among others, Wireless Capsule Endoscopy (WCE) aims to transmit better quality images. For this, the Ultra Wideband (UWB) frequency band is becoming a good alternative to currently allocated frequencies for in-body networks, allowing higher data rate and having a low power transmission. Common channel characterization in WBANs are performed in frequency domain, i.e., analyzing the received power as a function of frequency. Nevertheless, indepth studies in delay domain analyzing the impulse response of the channel are barely considered in current literature. In this paper, an initial study in delay domain, i.e., the Power Delay Profile (PDP) characteristics, is performed. Moreover, a comparison between the channel response in frequency and delay domain is performed. This work gives an insightful view of the impulse response of the channel for in-body to on-body communications. For that, an extensive campaign of phantom measurements and software simulations are conducted. ; This work was supported by the European Union's H2020:MSCA:ITN program for the "Wireless In-body Environment Communication- WiBEC" project under the grant agreement no. 675353. This work was also funded by by the European Union's H2020: MSCA: ITN program for the "mmWave Communications in the Built Environments - WaveComBE" project under the grant agreement no. 766231. ; Pérez-Simbor, S.; Garcia-Pardo, C.; Cardona Marcet, N. (2019). Initial Delay Domain UWB Channel Characterization for In-body Area Networks. IEEE. 1-5. https://doi.org/10.1109/ISMICT.2019.8743767 ; S ; 1 ; 5

Network slicing is one of the key enabling technologies for 5G networks. It allows infrastructure owners to assign resources to service providers (tenants), which will afterwards use them to satisfy their end-user demands. This paradigm, which changes the way networks have been traditionally managed, was initially proposed in the wired realm (core networks). More recently, the scientific community has paid attention to the integration of network slicing in wireless cellular technologies (LTE). However, there are not many works addressing the challenges that appear when trying to exploit slicing techniques over WiFi networks, in spite of their growing relevance. In this paper we propose a novel method of proportionally distributing resources in WiFi networks, by means of the airtime. We develop an analytical model, which shed light on how such resources could be split. The validity of the proposed model is assessed by means of simulation-based evaluation over the ns-3 framework. ; This work has been supported in part by the European Commission and the Spanish Government (Fondo Europeo de desarrollo Regional, FEDER) by means of the EU H2020 NECOS (777067) and ADVICE (TEC2015-71329) projects, respectively.

In Law No. 31 of 2009 concerning Meteorology, Climatology and Geophysics and Government Regulation No. 11 of 2016 concerning Meteorology, Climatology and Geophysics Services related to BMKG, government institutions, and aid provider institutions Better as routine or as early. Problems related to the challenges in providing quality services and service information about weather and related interests do not only occur in Indonesia, but also in other countries. This is due to limited resources needed by this country. This problem was then carried out by BMKG to find alternative solutions to improve service information and complexity. The alternative that can be done is by partnering with the private sector or community. This study answers the questions and needs stated above, namely by making a prototype. Portable devices for easy use BMKG can use easy and simple. Thus many people and the private sector can use the prototype and related information and can be provided easily and simply. The technique used in taking measurement parameters is not expensive and the climate uses sensors installed in the NodeMCU v3 microcontroller. 5 weather and climate measurement parameters are used, namely air temperature & humidity, air pressure, wind speed, sunlight intensity and rainfall. The use of solar panels and dry batteries functioned as a power supply from this prototype design. The measurement results from the sensor by the microcontroller, then sent every 1 minute to the Raspberry Pi available in the operating room via a LAN connection and then recorded by history data. Then the data from the Raspberry is sent to the Web DB & Server Server every 1 hour via a VPN internet connection. Users can use weather information from the measurement results by accessing the Web Server via a VPN internet connection using a username & password that was previously registered. Keywords: Portable, Sensor, Microcontroller, Wireless, VPN

Building networks in rural areas is difficult because of the tough rural environments and low return to the service operators on investment. Rural networking and their applications in education, health, community development, and business development are essential to the daily life for both inhabitants and visitors. They further bring opportunities in job and business which play a key role in developing most underdeveloped rural areas. Moreover, rural communication will grow with the initial investment in rural networking. It will become the major communication market and generate large profits to service operators and equipment manufacturers. Wireless networking is generally considered a solution to these difficulties in rural conditions. Compared with the wireline construction, setting up wireless networks is faster, more flexible, and less expensive. In addition, many new and advanced wireless technologies have enabled universal communication to rural and remote areas in a profitable manner. Yet special technological requirements need to be met for wireless networking to become feasible in rural areas.

Rapid climate change is exposing subsistence farmers to enormous challenges, especially in Sub-Saharan Africa. Several foreign aid programs have been set up to cope with these issues, many of which have focused on technical solutions. However, there seems to be a large gap between scientific research and the needs of local communities. Besides focusing on new ways to improve the resilience of local food production, there is also an urgent need to adapt available knowledge to the local context. Based on experiences from a project to co-create community networks in Togo in 2020, we aim to empower local stakeholders, including farmers and scientists, to adapt existing knowledge of sustainable crop farming to current practices. New modes of knowledge exchange can be established with the help of participatory design. These methods may help to foster a collective approach to learning that enables people to cope with global challenges on a local level, all while valuing the traditional practices of local farmers and enriching them with scientific knowledge.

The ability to perform traffic differentiation is a promising feature of the current Medium Access Control (MAC) in Wireless Local Area Networks (WLANs). The Enhanced Distributed Channel Access (EDCA) protocol for WLANs proposes up to four Access Categories (AC) that can be mapped to different traffic priorities. High priority ACs are allowed to transmit more often than low priority ACs, providing a way of prioritising delay sensitive traffic like voice calls or video streaming. Further, EDCA also considers the intricacies related to the management of multiple queues, virtual collisions and traffic differentiation. Nevertheless, EDCA falls short in efficiency when performing in dense WLAN scenarios. Its collision-prone contention mechanism degrades the overall throughput to the point of starving low priority ACs, and produce priority inversions at high number of contenders. Carrier Sense Multiple Access with Enhanced Collision Avoidance (CSMA/ECA) is a compatible MAC protocol for WLANs which is also capable of providing traffic differentiation. Contrary to EDCA, CSMA/ECA uses a contention mechanism with a deterministic backoff technique which is capable of constructing collision-free schedules for many nodes with multiple active ACs, extending the network capacity without starving low priority ACs, as experienced in EDCA. This work analyses traffic differentiation with CSMA/ECA by describing the mechanisms used to construct collision-free schedules with multiple queues. Additionally, evaluates the performance under different traffic conditions and a growing number of contenders. Furthermore, it introduces a way to eliminate Virtual Collisions (VC), which also contributes to the throughput degradation in EDCA WLANs. Simulation tests are performed using voice and video packet sources that emulate commonly used codecs. Results show CSMA/ECA outperforming EDCA in different commonly-found scenarios with high number of users, including when both MAC protocols coexist in the same WLAN. ; This work was partially supported by the Spanish Government / FEDER under project CISNETS (TEC2012-32354), Catalan Government (2017-SGR-1188), and by a Gift from the Cisco University Research Program (CG#890107, Towards Deterministic Channel Access in High-Density WLANs) Fund, a corporate advised fund of Silicon Valley Community Foundation.

Intro -- Cover Page -- Title Page -- Copyright Page -- Contents -- Preface -- Acknowledgments -- Introduction -- 1. Sacred Cities, Stubborn People -- 2. Voices in the West -- 3. God Is Wireless -- 4. Ethical Dilemmas and Technical Obstacles: Navigating Early Television -- 5. Distance and Discipline: Television, Home, and Family -- 6. Drawing Borders: Zion Online -- 7. Community Here, Community Hereafter -- Conclusion: Control and Compromise -- Notes -- Index -- About the Author -- Back Cover.