21 research outputs found
Secure Communication in Disaster Scenarios
WĂ€hrend Naturkatastrophen oder terroristischer AnschlĂ€ge ist die bestehende Kommunikationsinfrastruktur hĂ€ufig ĂŒberlastet oder fĂ€llt komplett aus. In diesen Situationen können mobile GerĂ€te mithilfe von drahtloser ad-hoc- und unterbrechungstoleranter Vernetzung miteinander verbunden werden, um ein Notfall-Kommunikationssystem fĂŒr Zivilisten und Rettungsdienste einzurichten. Falls verfĂŒgbar, kann eine Verbindung zu Cloud-Diensten im Internet eine wertvolle Hilfe im Krisen- und Katastrophenmanagement sein.
Solche Kommunikationssysteme bergen jedoch ernsthafte Sicherheitsrisiken, da Angreifer versuchen könnten, vertrauliche Daten zu stehlen, gefĂ€lschte Benachrichtigungen von Notfalldiensten einzuspeisen oder Denial-of-Service (DoS) Angriffe durchzufĂŒhren. Diese Dissertation schlĂ€gt neue AnsĂ€tze zur Kommunikation in Notfallnetzen von mobilen GerĂ€ten vor, die von der Kommunikation zwischen MobilfunkgerĂ€ten bis zu Cloud-Diensten auf Servern im Internet reichen. Durch die Nutzung dieser AnsĂ€tze werden die Sicherheit der GerĂ€te-zu-GerĂ€te-Kommunikation, die Sicherheit von Notfall-Apps auf mobilen GerĂ€ten und die Sicherheit von Server-Systemen fĂŒr Cloud-Dienste verbessert
iOS Technologies & Frameworks
Appleâs mobile platform â iOS â currently generates the largest amount of revenue out of all mobile app stores. The majority of iDevices run the latest major iOS version (iOS 10) due to Apple usersâ tendency to update their devices. Consequently, iOS developers are pressured into keeping their apps up to date.
Advantages to updating apps consist of new features and adapting apps to the platformâs hardware and software evolution. However, this does not always happen. There are apps, some popular (with many users), which either receive slow updates, or not at all. The main consequence of developers not updating to the latest tendencies (i.e. user interface or API changes) is the degradation of their appsâ user experience. This subpar user experience leads to a decrease in the number of installs (and sales) and a search for alternatives that have been updated to support the latest firmware iteration fully.
We identified a common pattern amongst ten apps which have subpar reviews on the App Store: excessive battery consumption and lack of user onboarding were just a few of the ssues. Above all, almost all those apps belong to the top 1% of apps (which generate 94% of the App Storeâs revenue), so the lack of focus on the user experience is unfortunate considering their massive user bases.
We listed the available resources for those wanting to develop or improve iOS apps. Given these requisites, we studied the possibility of developing a mobile app that adopted good engineering practices and, above all, focused on delivering an excellent user experience in a given timeframe of six months.
The appâs idea consisted of a wish list management app called Snapwish that allows the user to take photos of objects they want, create wish lists, and share them with family and friends. The app allows for offline usage, with data syncing automatically (in real-time) without user intervention when the appâs Internet connection is present.
We tested Snapwish thoroughly to measure the quality of its implementation. Profiling helped assert that core metrics like CPU and memory usage, network data requests and energy consumption were within acceptable values while unit and user interface tests served to validate our code functionally. Furthermore, our team of five beta testers provided valuable feedback and suggestions.
Ultimately, the six-month timeframe proved to be insufficient in regards to a release on the App Store, as Snapwish remains in the latter beta stages at the time of writing. This delay is mostly attributed to a lengthy testing process. Thus, we plan on releasing it in the first trimester of 2017.Hoje em dia, a plataforma mĂłvel da Apple â iOS â Ă© a que tem maior revenue em aplicaçÔes mĂłveis. A maior parte dos dispositivos mĂłveis iOS corre a versĂŁo mais atual (iOS 10), devido Ă tendĂȘncia dos seus utilizadores em atualizar o sistema operativo com frequĂȘncia. Consequentemente, os desenvolvedores da plataforma sĂŁo pressionados para manterem as suas apps atualizadas.
Algumas das vantagens das atualizaçÔes consiste em adicionar novas funcionalidades e adaptar as apps Ă evolução do hardware e do software da plataforma. Contudo, isto nem sempre e verifica. Existem muitas apps, algumas âpopularesâ (com muitas instalaçÔes) cuja atualização demora ou nĂŁo acontece. A principal consequĂȘncia da nĂŁo atualização das apps Ă s tendĂȘncias atuais, quer em termos de interação, quer em termos de mecanismos de proteção de dados, consumo de bateria e outros, Ă© a degradação da experiĂȘncia de quem as utiliza, consequentemente, a diminuição do nĂșmero de instalaçÔes (e vendas) e a crescente procura de alternativas que tenham estes princĂpios em conta.
Foi identificado um padrĂŁo comum em dez aplicaçÔes cujas classificaçÔes na App Store sĂŁo medĂocres: um consumo exagerado de bateria e falta de user onboarding foram apenas alguns dos problemas. Acima de tudo, quase todas pertencem ao 1% de aplicaçÔes que geram 94% das receitas da App Store. A falta de foco na experiĂȘncia do utilizador Ă© infeliz considerando as enormes bases de utilizadores dessas aplicaçÔes.
Foram listados os recursos disponĂveis para quem pretende desenvolver ou melhorar uma aplicação iOS. Dadas essas premissas, foi estudada a possibilidade de desenvolver uma aplicação mĂłvel que adote boas prĂĄticas de engenharia e, acima de tudo, foque na experiĂȘncia do utilizador, num perĂodo de seis meses.
A ideia para a aplicação consistiu num gestor de listas de desejos designada Snapwish que permite tirar fotos de objetos que o utilizador deseja, criar listas, e partilhå-las com amigos e familiares. Além disso, a app permite o uso offline e os dados são sincronizados em tempo real sem intervenção do utilizador quando a app dispÔe de uma conexão à Internet.
A nossa aplicação foi testada extensivamente para medir o nĂvel de qualidade da sua implementação.
O profiling ajudou em constatar que métricas fundamentais como o consumo de CPU e memória, pedidos de dados de rede e de consumo de energia (bateria) estavam dentro dos parùmetros aceitåveis. Além disso, uma equipa de cinco beta-testers contribuiu com comentårios e sugestÔes de grande valor.
Em Ășltima anĂĄlise, o prazo de seis meses revelou-se insuficiente em relação ao lançamento da app na App Store. O Snapwish permanece numa fase beta avançada (no momento da escrita desta tese). Este atraso Ă© principalmente atribuĂdo a um extenso processo de testes.
Assim, pretendemos lançar a aplicação no primeiro trimestre de 2017
Cloud Services Brokerage for Mobile Ubiquitous Computing
Recently, companies are adopting Mobile Cloud Computing (MCC) to efficiently deliver enterprise services to users (or consumers) on their personalized devices. MCC is the facilitation of mobile devices (e.g., smartphones, tablets, notebooks, and smart watches) to access virtualized services such as software applications, servers, storage, and network services over the Internet. With the advancement and diversity of the mobile landscape, there has been a growing trend in consumer attitude where a single user owns multiple mobile devices. This paradigm of supporting a single user or consumer to access multiple services from n-devices is referred to as the Ubiquitous Cloud Computing (UCC) or the Personal Cloud Computing.
In the UCC era, consumers expect to have application and data consistency across their multiple devices and in real time. However, this expectation can be hindered by the intermittent loss of connectivity in wireless networks, user mobility, and peak load demands.
Hence, this dissertation presents an architectural framework called, Cloud Services Brokerage for Mobile
Ubiquitous Cloud Computing (CSB-UCC), which ensures soft real-time and reliable services consumption on multiple devices of users. The CSB-UCC acts as an application middleware broker that connects the n-devices of users to the multi-cloud services. The designed system determines the multi-cloud services based on the user's subscriptions and the n-devices are determined through device registration on the broker. The preliminary evaluations of the designed system shows that the following are achieved: 1) high scalability through the adoption of a distributed architecture of the brokerage service, 2) providing soft real-time application synchronization for consistent user experience through an enhanced mobile-to-cloud proximity-based access technique, 3) reliable error recovery from system failure through transactional services re-assignment to active nodes, and 4) transparent audit trail through access-level and context-centric provenance
Static Web content distribution and request routing in a P2P overlay
The significance of collaboration over the Internet has become a corner-stone of modern computing, as the essence of information processing and content management has shifted to networked and Webbased systems. As a result, the effective and reliable access to networked resources has become a critical commodity in any modern infrastructure.
In order to cope with the limitations introduced by the traditional client-server networking model, most of the popular Web-based services have employed separate Content Delivery Networks (CDN) to distribute the server-side resource consumption. Since the Web applications are often latency-critical, the CDNs are additionally being adopted for optimizing the content delivery latencies perceived by the Web clients. Because of the prevalent connection model, the Web content delivery has grown to a notable industry. The rapid growth in the amount of mobile devices further contributes to the amount of resources required from the originating server, as the content is also accessible on the go.
While the Web has become one of the most utilized sources of information and digital content, the openness of the Internet is simultaneously being reduced by organizations and governments preventing access to any undesired resources. The access to information may be regulated or altered to suit any political interests or organizational benefits, thus conflicting with the initial design principle of an unrestricted and independent information network.
This thesis contributes to the development of more efficient and open Internet by combining a feasibility study and a preliminary design of a peer-to-peer based Web content distribution and request routing mechanism. The suggested design addresses both the challenges related to effectiveness of current client-server networking model and the openness of information distributed over the Internet. Based on the properties of existing peer-to-peer implementations, the suggested overlay design is intended to provide low-latency access to any Web content without sacrificing the end-user privacy. The overlay is additionally designed to increase the cost of censorship by forcing a successful blockade to isolate the censored network from the rest of the Internet
XML Messaging for Mobile Devices
In recent years, XML has been widely adopted as a universal format for structured data. A variety of XML-based systems have emerged, most prominently SOAP for Web services, XMPP for instant messaging, and RSS and Atom for content syndication. This popularity is helped by the excellent support for XML processing in many programming languages and by the variety of XML-based technologies for more complex needs of applications.
Concurrently with this rise of XML, there has also been a qualitative expansion of the Internet's scope. Namely, mobile devices are becoming capable enough to be full-fledged members of various distributed systems. Such devices are battery-powered, their network connections are based on wireless technologies, and their processing capabilities are typically much lower than those of stationary computers.
This dissertation presents work performed to try to reconcile these two developments. XML as a highly redundant text-based format is not obviously suitable for mobile devices that need to avoid extraneous processing and communication. Furthermore, the protocols and systems commonly used in XML messaging are often designed for fixed networks and may make assumptions that do not hold in wireless environments.
This work identifies four areas of improvement in XML messaging systems: the programming interfaces to the system itself and to XML processing, the serialization format used for the messages, and the protocol used to transmit the messages. We show a complete system that improves the overall performance of XML messaging through consideration of these areas.
The work is centered on actually implementing the proposals in a form usable on real mobile devices. The experimentation is performed on actual devices and real networks using the messaging system implemented as a part of this work. The experimentation is extensive and, due to using several different devices, also provides a glimpse of what the performance of these systems may look like in the future.Matkapuhelimien ja muiden mobiililaitteiden mÀÀrÀ on kasvanut erittÀin nopeasti viime vuosina. Laitteiden pieni koko, niiden tarjoamat ohjelmointimahdollisuudet ja langattomat verkkoyhteydet mahdollistavat Internet- ja muiden verkkosovellusten kÀytön kaikkialla. Akusta johtuva rajallinen kÀyttöaika, heikko suoritusteho ja verkkokÀytön vaatima virta ja aika toimivat kuitenkin selkeinÀ rajoitteina mobiililaitteiden mahdollisuuksille, ja jotta mobiilimaailma ei joutuisi kokonaan tulevaisuuden Internetin ulkopuolelle, jÀrjestelmien ja sovellusten suunnittelussa on otettava sen erityispiirteet huomioon.
Tulevaisuuden verkkosovelluksissa suoran pÀÀtelaitteiden vÀlisen viestinnÀn odotetaan olevan keskeinen osa sovelluksen toimintaa. Nyky-InternetissÀ tÀllaisessa viestinnÀssÀ kÀytetÀÀn yhÀ useammin XML-kieltÀ, joka laajennettavuutensa ja helppokÀyttöisyytensÀ ansiosta vÀhentÀÀ sovelluskehittÀjÀn taakkaa. XML-kielen ongelmina ovat kuitenkin sen vaatimat suuret tiedonsiirto- ja kÀsittelyajat, jotka ovat olleet esteenÀ XML:n laajalle kÀytölle mobiiliympÀristöissÀ.
VÀitöskirja tutkii XML-pohjaisen laitteiden vÀlisen viestinnÀn perusedellytyksiÀ mobiililaitteilla langattomissa verkoissa. Keskeiset tutkimuskohteet ovat tiivis ja tehokkaasti kÀsiteltÀvÀ XML-esitysmuoto, XML:n kÀsittelyyn paremmin sopivat ohjelmointirajapinnat ja mobiiliympÀristön viestiprotokollat.
Työn tuloksena on syntynyt mobiililaitteille suunniteltu XML-pohjainen viestintÀjÀrjestelmÀ, joka on sellaisenaan kÀytettÀvissÀ verkkosovellusten perustana. JÀrjestelmÀlle on suoritettu kattavat mittaukset, jotka osoittavat jÀrjestelmÀn sopivuuden kÀyttötarkoitukseensa. Tulosten analyysissa otetaan myös huomioon, miten jÀrjestelmÀn eri ominaisuudet sopivat kuhunkin mobiililaitteiden tukemaan ympÀristöön, sekÀ tarkastellaan, miltÀ tulevaisuuden mobiililaitteiden suorituskyky saattaisi nÀyttÀÀ
Intelligent Sensor Networks
In the last decade, wireless or wired sensor networks have attracted much attention. However, most designs target general sensor network issues including protocol stack (routing, MAC, etc.) and security issues. This book focuses on the close integration of sensing, networking, and smart signal processing via machine learning. Based on their world-class research, the authors present the fundamentals of intelligent sensor networks. They cover sensing and sampling, distributed signal processing, and intelligent signal learning. In addition, they present cutting-edge research results from leading experts
AFFORDABLE WATER QUALITY ANALYSIS: A PROPOSED FRAMEWORK FOR THE DEVELOPMENT AND REGULATION OF LOW-COST WATER QUALITY MONITORING DEVICES
Access to adequate supplies of potable water is a key driver of human health. Physical and chemical treatment processes are frequently necessary to make water safe to drink. Monitoring of water before, during, and after treatment is an essential component of the provision of potable water, and most aspects of water quality monitoring require electronic devices to augment human senses. Every nation sets rules governing the treatment and monitoring of drinking water, in an attempt to continuously ensure potability of drinking water supplies. Presently, however, the regulations governing the design of common electronic devices for water quality monitoring are developed and published by just two organizations â the US Environmental Protection Agency (EPA) and the International Organization for Standardization (ISO). The implications of this regulatory situation on drinking water quality monitoring, particularly in low-resource settings, are largely (perhaps completely) unaddressed in existing literature.
Turbidity, which may be summarized as cloudiness in a body of liquid due to the scattering of light by particles suspended in that body, is internationally recognized as a simple and useful monitoring parameter for drinking water treatment. Using turbidity as an exemplar, this dissertation examines the structure of regulations governing the design of water quality monitoring devices, and the potential impact that regulatory structure has on the design, fabrication, and marketing of water quality monitoring devices, including both closed-source and open-source technology. National turbidity monitoring requirements for several nations, and the turbidity guidelines promulgated by the World Health Organization, are compared. The EPA and ISO turbidimeter regulations are also examined in relation to these national and international turbidity monitoring requirements. Design variables and requirements are identified which are generally necessary to ensure a properly functioning turbidimeter, but which are not explicitly stated in EPA and ISO turbidimeter regulations.
Aspects of the commercial turbidimeter market, and EPA and ISO turbidimeter regulations, which are likely burdensome for water quality monitoring efforts in low-resource settings (such as rural communities in developing countries), are explored â perhaps chief among these being cost. While production of open-source turbidimeter designs provides a potential solution for turbidity monitoring in low-resource settings, open-source turbidimeter design efforts are currently far from able to meet global needs.
To provide supplementary regulatory requirements for EPA and ISO turbidimeter standards, and to spur the development of market-ready open-source turbidimeter designs, a framework titled the Affordable Water Quality Analysis (AWQUA) device development is proposed. It consists of a turbidity-specific regulatory section, and a general water quality monitoring device development guidance section. Proper use of this guidance section is intended to strengthen open-source water quality monitoring device development efforts and encourage the production of device documentation suitable to demonstrate compliance with the regulatory section.
An important contribution of this dissertation effort is the development and detailed description of four different examples of novel, low-cost, open-source water quality monitoring devices that motivated the proposed supplementary framework, informed its design, and serve to illustrate its application. First, a low-cost, open-source handheld turbidimeter based on a simple digital light detection sensor is detailed and discussed. The design, fabrication, and testing of this device served as a motivator for the development of the proposed supplementary turbidimeter development guidelines proposed. The turbidimeter nearly meets international regulatory guidelines, was fully described in a peer-reviewed publication, and is believed to be the most detailed open-source design of a digital turbidimeter publicly available (at the time of this writing) and yet contains several subtle but critical design flaws that are unaddressed in current national and international turbidimeter regulations. This prototype thus motivated and informed the design of the proposed new regulatory framework. Subsequently, three other promising open-source water quality monitoring designs were developed, fabricated, and evaluated under the AWQUA Framework: (1) a second low-cost open-source handheld turbidimeter, based on a highly precise light-to-voltage analog sensing setup; (2) a highly compact low-cost open-source inline turbidimeter, designed for continuous immersive monitoring of turbidity in surface waters; and (3) a low-cost open-source jar tester â a device used to evaluate certain physical and chemical treatments employed in drinking water treatment to reduce turbidity. These designs and the associated framework that grew from them are contributions toward the provision of âAffordable Water Quality Analysisâ (AWQUA) capabilities for communities in low-resource settings