Architecting and deploying IoT smart applications: A performance–oriented approach

open7siLayered internet of things (IoT) architectures have been proposed over the last years as they facilitate understanding the roles of different networking, hardware, and software components of smart applications. These are inherently distributed, spanning from devices installed in the field up to a cloud datacenter and further to a user smartphone, passing by intermediary stages at different levels of fog computing infrastructure. However, IoT architectures provide almost no hints on where components should be deployed. IoT Software Platforms derived from the layered architectures are expected to adapt to scenarios with different characteristics, requirements, and constraints from stakeholders and applications. In such a complex environment, a one-size-fits-all approach does not adapt well to varying demands and may hinder the adoption of IoT Smart Applications. In this paper, we propose a 5-layer IoT Architecture and a 5-stage IoT Computing Continuum, as well as provide insights on the mapping of software components of the former into physical locations of the latter. Also, we conduct a performance analysis study with six configurations where components are deployed into different stages. Our results show that different deployment configurations of layered components into staged locations generate bottlenecks that affect system performance and scalability. Based on that, policies for static deployment and dynamic migration of layered components into staged locations can be identified.openZyrianoff I.; Heideker A.; Silva D.; Kleinschmidt J.; Soininen J.-P.; Cinotti T.S.; Kamienski C.Zyrianoff I.; Heideker A.; Silva D.; Kleinschmidt J.; Soininen J.-P.; Cinotti T.S.; Kamienski C

Raamistik mobiilsete asjade veebile

Internet on oma arengus läbi aastate jõudnud järgmisse evolutsioonietappi - asjade internetti (ingl Internet of Things, lüh IoT). IoT ei tähista ühtainsat tehnoloogiat, see võimaldab eri seadmeil - arvutid, mobiiltelefonid, autod, kodumasinad, loomad, virtuaalsensorid, jne - omavahel üle Interneti suhelda, vajamata seejuures pidevat inimesepoolset seadistamist ja juhtimist. Mobiilseadmetest nagu näiteks nutitelefon ja tahvelarvuti on saanud meie igapäevased kaaslased ning oma mitmekülgse võimekusega on nad motiveerinud teadustegevust mobiilse IoT vallas. Nutitelefonid kätkevad endas võimekaid protsessoreid ja 3G/4G tehnoloogiatel põhinevaid internetiühendusi. Kuid kui kasutada seadmeid järjepanu täisvõimekusel, tühjeneb mobiili aku kiirelt. Doktoritöö esitleb energiasäästlikku, kergekaalulist mobiilsete veebiteenuste raamistikku anduriandmete kogumiseks, kasutades kergemaid, energiasäästlikumaid suhtlustprotokolle, mis on IoT keskkonnale sobilikumad. Doktoritöö käsitleb põhjalikult energia kokkuhoidu mobiilteenuste majutamisel. Töö käigus loodud raamistikud on kontseptsiooni tõestamiseks katsetatud mitmetes juhtumiuuringutes päris seadmetega.The Internet has evolved, over the years, from just being the Internet to become the Internet of Things (IoT), the next step in its evolution. IoT is not a single technology and it enables about everything from computers, mobile phones, cars, appliances, animals, virtual sensors, etc. that connect and interact with each other over the Internet to function free from human interaction. Mobile devices like the Smartphone and tablet PC have now become essential to everyday life and with extended capabilities have motivated research related to the mobile Internet of Things. Although, the recently developed Smartphones enjoy the high performance and high speed 3G/4G mobile Internet data transmission services, such high speed performances quickly drain the battery power of the mobile device. This thesis presents an energy efficient lightweight mobile Web service provisioning framework for mobile sensing utilizing the protocols that were designed for the constrained IoT environment. Lightweight protocols provide an energy efficient way of communication. Finally, this thesis highlights the energy conservation of the mobile Web service provisioning, the developed framework, extensively. Several case studies with the use of the proposed framework were implemented on real devices and has been thoroughly tested as a proof-of-concept.https://www.ester.ee/record=b522498

A comparative node evaluation model for highly heterogeneous massive‐scale Internet of Things‐Mist networks

Internet of Things (IoT) is a new technology that is driving the connection of billions of devices around the world. Because these devices are often resource‐constrained and very heterogeneous, this presents unique challenges. To address some of these challenges, new paradigms of Edge and Fog are emerging to bring computational resources of the IoT networks from remote devices like cloud closer to the end‐devices. Mist computing is a new paradigm that attempts to make use of the more resource‐rich nodes that are closer than Edge nodes to end‐users. Since these nodes might have enough resources to host services, execute tasks or even run containers, the utilization of network resources might be improved, and delay reduced by utilizing these nodes. The nodes must, therefore, be assessed to determine which nodes should offer resources to other nodes based on their situation. In this article, a new comparative assessment model for ranking Mist nodes in highly heterogeneous massive‐scale IoT networks in order to discover nodes that can offer their resources is proposed. The Mist nodes are evaluated based on parameters like resources, connections, applications, and environmental parameters to heuristically compare the neighbors with a novel learning‐to‐rank method to predict a suitability score for each node. The most suitable neighbor is then selected based on the score, with load balancing accomplished by a second chance method. When evaluating the performance, the results show that the proposed method succeeds in identifying resource‐rich nodes, while considering the selection of other nodes.publishedVersio

Disturbed weather measurements in atmospheric electricity using an instrumented van

Precipitation currents have been measured using an exposed receiver. Compensation for field currents has been achieved by subtracting the field currents to a probe, suitably amplified, from the total current to the exposed receiver. The potential gradient has been measured using a field mill, the theory of which has been rederived. Wind speed was also measured with a contact cup anemometer. The apparatus was installed in a Land Rover thus providing a mobile observatory. The results obtained led to an analysis of the conditions in quiet rain when the inverse relation is not evident. The slope of the regression line between current and potential gradient is shown to depend upon the phase angle of lag between the current-time and potential gradient-time records. A method for deducing the lag or lead in records when the mirror image effect is not apparent has been evolved from consideration of the Lissajous plots first described by RAMSAY (1960). The method has been used to show some support for the ideas of CHALMERS (1965) concerning the behaviour of records taken beneath approaching and developing cloud systems. Both the approaching and developing situations have been observed. An experiment has been described which conclusively shows the pylon to be the source of negative space charge associated with power lines in mist or fog. An explanation is offered in terms of the different mobilities of free electrons and positive ions which are supposed to be formed by ionisation due to tracking across the damp insulators. The electrons are shown during the negative phase of the line voltage to travel a distance before their capture which is greater than that from which they can be drawn back when the polarity of the alternating voltage changes. Measurements of polar conductivities at two levels, above and below the 0ºC isotherm, have been made during steady snowfall with a Gerdien conductivity chamber. From these measurements the charge separation rate in the melting region has been estimated

Characteristic weather phenomena of California : a regional analysis based on aeronautical weather observations

During the fiscal year beginning July 1, 1928, the Daniel Guggenheim Fund for the Promotion of Aeronautics maintained an experimental meteorological service for the benefit of air transportation between San Francisco and Los Angeles. The system was designed as a first approach toward a model weather reporting organization for air traffic. Its main feature was the gathering of simultaneous weather observations from about 35 stations in Southern and Central California covering an area of, roughly, 65,000 square miles. The observation hours were 6.30 a.m., 8 a.m., 9.30 a.m., 11 a.m., 12.30 p.m., and 3.30 p.m., 120th meridian time. The regular Weather Bureau observations furnished additional data for 5 a.m. and 5 p.m. A description of the organization has been published by E. H. Bowie. Since the service was organized strictly for the purpose of informing airplane pilots of weather conditions over their routes and not with a view of furnishing a fertile field for meteorological investigations, certain instrumental readings which are important in meteorological research were not provided. Thus humidity observations are lacking, except as subsequently obtained from the few but more thoroughly equipped stations of the U. S. Weather Bureau, the U. S. Navy and the University of California. A series of airplane ascents made at the Naval Air Station at San Diego provided pressure, temperature and relative humidity observations from the upper atmosphere for part of the period investigated. Three pilot balloon stations were established by the Fund to supplement those of the Government, so that ample free air wind data are available. Non-professional part-time observers were employed at most of the stations. For this reason, inaccuracies are likely to have lessened the value of the reports. These errors occurred chiefly in the determination of cloud forms. When the uncertainties of cloud classification and the diffculties it presents even to the trained meteorologist are fully appreciated, the errors in these observations are not surprising. It is the opinion of the authors that the cloud forms herein recorded are for all practical purposes correct. During the year in which this service was conducted by the Fund, some interesting data were collected to add to the knowledge of meteorological conditions in California. This applies particularly to the movement of fronts and the development, distribution and dissipation of the persistent and frequent fogs in the area. Some of these results will be presented below

Mobiilse värkvõrgu protsessihaldus

Värkvõrk, ehk Asjade Internet (Internet of Things, lüh IoT) edendab lahendusi nagu nn tark linn, kus meid igapäevaselt ümbritsevad objektid on ühendatud infosüsteemidega ja ka üksteisega. Selliseks näiteks võib olla teekatete seisukorra monitoorimissüsteem. Võrku ühendatud sõidukitelt (nt bussidelt) kogutakse videomaterjali, mida seejärel töödeldakse, et tuvastada löökauke või lume kogunemist. Tavaliselt hõlmab selline lahendus keeruka tsentraalse süsteemi ehitamist. Otsuste langetamiseks (nt milliseid sõidukeid parasjagu protsessi kaasata) vajab keskne süsteem pidevat ühendust kõigi IoT seadmetega. Seadmete hulga kasvades võib keskne lahendus aga muutuda pudelikaelaks. Selliste protsesside disaini, haldust, automatiseerimist ja seiret hõlbustavad märkimisväärselt äriprotsesside halduse (Business Process Management, lüh BPM) valdkonna standardid ja tööriistad. Paraku ei ole BPM tehnoloogiad koheselt kasutatavad uute paradigmadega nagu Udu- ja Servaarvutus, mis tuleviku värkvõrgu jaoks vajalikud on. Nende puhul liigub suur osa otsustustest ja arvutustest üksikutest andmekeskustest servavõrgu seadmetele, mis asuvad lõppkasutajatele ja IoT seadmetele lähemal. Videotöötlust võiks teostada mini-andmekeskustes, mis on paigaldatud üle linna, näiteks bussipeatustesse. Arvestades IoT seadmete üha suurenevat hulka, vähendab selline koormuse jaotamine vähendab riski, et tsentraalne andmekeskust ülekoormamist. Doktoritöö uurib, kuidas mobiilsusega seonduvaid IoT protsesse taoliselt ümber korraldada, kohanedes pidevalt muutlikule, liikuvate seadmetega täidetud servavõrgule. Nimelt on ühendused katkendlikud, mistõttu otsuste langetus ja planeerimine peavad arvestama muuhulgas mobiilseadmete liikumistrajektoore. Töö raames valminud prototüüpe testiti Android seadmetel ja simulatsioonides. Lisaks valmis tööriistakomplekt STEP-ONE, mis võimaldab teadlastel hõlpsalt simuleerida ja analüüsida taolisi probleeme erinevais realistlikes stsenaariumites nagu seda on tark linn.The Internet of Things (IoT) promotes solutions such as a smart city, where everyday objects connect with info systems and each other. One example is a road condition monitoring system, where connected vehicles, such as buses, capture video, which is then processed to detect potholes and snow build-up. Building such a solution typically involves establishing a complex centralised system. The centralised approach may become a bottleneck as the number of IoT devices keeps growing. It relies on constant connectivity to all involved devices to make decisions, such as which vehicles to involve in the process. Designing, automating, managing, and monitoring such processes can greatly be supported using the standards and software systems provided by the field of Business Process Management (BPM). However, BPM techniques are not directly applicable to new computing paradigms, such as Fog Computing and Edge Computing, on which the future of IoT relies. Here, a lot of decision-making and processing is moved from central data-centers to devices in the network edge, near the end-users and IoT sensors. For example, video could be processed in mini-datacenters deployed throughout the city, e.g., at bus stops. This load distribution reduces the risk of the ever-growing number of IoT devices overloading the data center. This thesis studies how to reorganise the process execution in this decentralised fashion, where processes must dynamically adapt to the volatile edge environment filled with moving devices. Namely, connectivity is intermittent, so decision-making and planning need to involve factors such as the movement trajectories of mobile devices. We examined this issue in simulations and with a prototype for Android smartphones. We also showcase the STEP-ONE toolset, allowing researchers to conveniently simulate and analyse these issues in different realistic scenarios, such as those in a smart city.  https://www.ester.ee/record=b552551