Sensing as a Service Model for Smart Cities Supported by Internet of Things

The world population is growing at a rapid pace. Towns and cities are accommodating half of the world's population thereby creating tremendous pressure on every aspect of urban living. Cities are known to have large concentration of resources and facilities. Such environments attract people from rural areas. However, unprecedented attraction has now become an overwhelming issue for city governance and politics. The enormous pressure towards efficient city management has triggered various Smart City initiatives by both government and private sector businesses to invest in ICT to find sustainable solutions to the growing issues. The Internet of Things (IoT) has also gained significant attention over the past decade. IoT envisions to connect billions of sensors to the Internet and expects to use them for efficient and effective resource management in Smart Cities. Today infrastructure, platforms, and software applications are offered as services using cloud technologies. In this paper, we explore the concept of sensing as a service and how it fits with the Internet of Things. Our objective is to investigate the concept of sensing as a service model in technological, economical, and social perspectives and identify the major open challenges and issues.Comment: Transactions on Emerging Telecommunications Technologies 2014 (Accepted for Publication

Link-layer Security in TSCH Networks: Effect on Slot Duration

International audienceThe IEEE802.15.4e-2012 standard is widely used in multi-hop wireless Industrial Internet of Things (IIoT)applications. In the Time-Slotted Channel Hopping (TSCH) mode, nodes are synchronized, and time iscut into timeslots. A schedule orchestrates all communications, resulting in high reliability and low poweroperations. A timeslot must be long enough for a node to send a data frame to its neighbor, and for thatneighbor to send back an acknowledgment. Shorter timeslots enable higher bandwidth and lower latency, yetthe minimal timeslot duration is limited by how long link-layer security operations take. We evaluate theoverhead of link-layer security in TSCH networks in terms of minimal timeslot length, memory footprint,and energy consumption. We implement full link-layer security on a range of hardware platforms, exploringdierent hardware/software implementation strategies. Through an extensive measurement campaign, wequantify the advantage of hardware accelerations for link-layer security, and show how the minimal durationof a timeslot varies between 9 ms and 88 ms for the most common conguration, depending on hardwaresupport. Furthermore, we also highlighted the impact that the timeslot duration has on both high-levelapplication design and energy consumption

Absinthin, an agonist of the bitter taste receptor hTAS2R46, uncovers an ER-to-mitochondria Ca2–shuttling event

Type 2 taste receptors (TAS2R) are G protein-coupled receptors first described in the gustatory system, but have also been shown to have extra-oral localizations, including airway smooth muscle (ASM) cells, in which TAS2R have been reported to induce relaxation. TAS2R46 is an unexplored subtype that responds to its highly specific agonist absinthin. Here, we first demonstrate that, unlike other bitter-taste receptor agonists, absinthin alone (1 μM) in ASM cells does not induce Ca2+ signals, but reduces histamine-induced cytosolic Ca2+ increases. To investigate this mechanism, we introduced into ASM cells aequorin-based Ca2+ probes targeted to the cytosol, sub-plasma membrane domain, or the mitochondrial matrix. We show that absinthin reduces cytosolic histamine-induced Ca2+-rises and simultaneously increases Ca2+-influx into mitochondria. We found that this effect is inhibited by the potent human TAS2R46 (hTAS2R46) antagonist 3β-hydroxydihydrocostunolide and is no longer evident in hTAS2R46-silenced ASM cells, indicating that it is hTAS2R46-dependent. Furthermore, these changes were sensitive to the mitochondrial uncoupler carbonyl cyanide p-(trifluoromethoxy)phenyl-hydrazone (FCCP); the mitochondrial calcium uniporter inhibitor KB-R7943 (carbamimidothioic-acid); the cytoskeletal disrupter latrunculin; and an inhibitor of the exchange protein directly activated by cAMP (EPAC), ESI-09. Similarly, the β2 agonist salbutamol also could induce Ca2+ shuttling from cytoplasm to mitochondria, suggesting that this new mechanism might be generalizable. Moreover, forskolin and an EPAC activator mimicked this effect in HeLa cells. Our findings support the hypothesis that plasma membrane receptors can positively regulate mitochondrial Ca2+ uptake, adding a further facet to the ability of cells to encode complex Ca2+ signals

Enabling SDN in VANETs: What is the Impact on Security?

The demand for safe and secure journeys over roads and highways has been growing at a tremendous pace over recent decades. At the same time, the smart city paradigm has emerged to improve citizens’ quality of life by developing the smart mobility concept. Vehicular Ad hoc NETworks (VANETs) are widely recognized to be instrumental in realizing such concept, by enabling appealing safety and infotainment services. Such networks come with their own set of challenges, which range from managing high node mobility to securing data and user privacy. The Software Defined Networking (SDN) paradigm has been identified as a suitable solution for dealing with the dynamic network environment, the increased number of connected devices, and the heterogeneity of applications. While some preliminary investigations have been already conducted to check the applicability of the SDN paradigm to VANETs, and its presumed benefits for managing resources and mobility, it is still unclear what impact SDN will have on security and privacy. Security is a relevant issue in VANETs, because of the impact that threats can have on drivers’ behavior and quality of life. This paper opens a discussion on the security threats that future SDN-enabled VANETs will have to face, and investigates how SDN could be beneficial in building new countermeasures. The analysis is conducted in real use cases (smart parking, smart grid of electric vehicles, platooning, and emergency services), which are expected to be among the vehicular applications that will most benefit from introducing an SDN architecture

Link quality aware channel allocation for multichannel body sensor networks.

Body Sensor Network (BSN) is a typical Internet-of-Things (IoT) application for personalized health care. It consists of economically powered, wireless and implanted medical monitoring sensor nodes, which are designed to continually collect the medical information of the target patients. Multichannel is often used in BSNs to reduce the spectrum competition of the tremendous sensor nodes and the problem of channel assignment has attracted much research attention. The health sensing data in BSNs is often required to be delivered to a sink node (or server) before a certain deadline for real time monitoring or health emergency alarm. Therefore, deadline is of significant importance for multichannel allocation and scheduling. The existing works, though designed to meet the deadline, often overlook the impact of the unreliable wireless links. As a result, the health sensing data can still be overdue because of the scheduled lossy links. Besides, potential collisions in the schedules also incur considerable delay in delivering the sensing data. In this paper, we propose a novel deadline- driven Link quality Aware Channel Assignment scheme (LACA), where link quality, deadlines and collisions are jointly considered. LACA prioritizes links with urgent deadlines and heavy collisions. Besides, LACA allows the exploition of the spare slots for retransmissions on lossy links, which can further reduce the retransmission delay. Extensive simulation experiments show that compared to the existing approaches, LACA can better utilize the wireless spectrum and achieve higher packet delivery ratio before the deadline.N/

Liberalising Deployment of Internet of Things Devices and Services in Large Scale Environments

There is an ongoing enormous expansion of Internet of Things devices andservices in everyday life, notably in novel large scale urban environments called Smart Cities. There, availability and uses of Internet of Things by end users and businesses is mainly palpable subject to prior knowledge of the relevant providers and use of dedicated applications that are associated with them. This current reality can be largely ascribed to the property of ‘‘verticality’’ of autonomous Internet of Things eco-systems in Smart Cities, where Internet of Things devices (e.g. sensor nodes) are connected over a communicationinfrastructure to service-cloud platforms that deliver and process data that isthen presented at the applications level. This paper explains possibilities for revolutionary changes needed towards liberalising deployment and visibility of IoT services and data associated with them. It advocates a conceptual approach termed ‘‘horizontal networking for Internet of Things’’ facilitating a more open and generic presence of Internet of Things through the proposed Internet of Things identification meta-data. The vision is built on needed novel practical features in the current communication setups. The features comprise combinations of the opportunistic and near-match search and discovery model, Internet of Things identification meta-data also reflecting the physical and network-based dimensions of devices’ locations, novel routing and data flow models emerging via Information-Centric Networking and changes required in the elements of the current telecommunicationinfrastructure and the Internet