119 research outputs found
Performance of constrained wireless devices in the Internet of Things
The Internet of Things is an emerging concept where every device, regardless of size, have their own connection to the Internet. This thesis examines what possible limitations are imposed on the functionality of resource constrained, wireless devices. Several different technologies are evaluated and compared, before a set of them is chosen for inclusion in an implementation, for example: IEEE 802.15.4, 6LoWPAN and CoAP. The implementation uses the Contiki operating system, and runs on a Texas Instruments CC2530 SoC. We then examine several different performance aspects of our implementation: the amount of data sent, memory usage and energy consumption. The results are discussed together with security aspects applicable to the Internet of things. The memory usage and power consumption were found to be severe issues. Due to the small amount of memory on the chip, all features could not be used at the same time. In addition, the power consumption was found to be too high for battery-powered usage, giving a lifetime of only 27 hours using a button cell battery. The conclusion is that hardware with more memory, and lower power consumption is required. New protocols for radio power-saving should also be developed and implemented in software.Internet of Things â sakernas internet â Ă€r ett framvĂ€xande koncept dĂ€r varje enhet, oavsett storlek, har en anslutning till Internet. Detta examensarbete undersöker vilka möjliga begrĂ€nsningar i funktionalitet detta fĂ„r pĂ„ trĂ„dlösa enheter med begrĂ€nsade resurser. Flera olika teknologier undersöks och jĂ€mförs, innan ett antal vĂ€ljs ut för att ingĂ„ i en implementation, till exempel: IEEE 802.15.4, 6LoWPAN och CoAP. Implementationen anvĂ€nder operativsystemet Contiki och körs pĂ„ ett Texas Instruments CC2530 SoC. Flera prestandaaspekter undersöks: mĂ€ngden skickad data, minnesanvĂ€ndning och energiförbrukning. Resultaten diskuteras tillsammans med sĂ€kerhetsaspekter att ta hĂ€nsyn till i Internet of Things. MinnesanvĂ€ndningen och energiförbrukningen Ă€r de mest problematiska omrĂ„dena. PĂ„ grund av chippets begrĂ€nsade mĂ€ngd minne kan inte all funktionalitet anvĂ€ndas samtidigt. Dessutom Ă€r energiförbrukningen för hög för lĂ€ngre tids strömförsörjning med batteri, vilket ger en livslĂ€ngd pĂ„ enbart 27 timmar med ett knappcellsbatteri. Slutsatsen Ă€r att hĂ„rdvara med mer minne och lĂ€gre energiförbrukning behövs. Nya protokoll för energibesparande radioanvĂ€ndning behöver ocksĂ„ utvecklas och implementeras i mjukvara
Improved Greedy Nonrandomness Detectors for Stream Ciphers
We consider the problem of designing distinguishers and nonrandomness detectors for stream ciphers using the maximum degree monomial test. We construct an improved algorithm to determine the subset of key and IV-bits used in the test. The algorithm is generic, and can be applied to any stream cipher. In addition to this, the algorithm is highly tweakable, and can be adapted depending on the desired computational complexity. We test the algorithm on the stream ciphers Grain-128a and Grain-128, and achieve significantly better results compared to an earlier greedy approach
Using TPM Secure Storage in Trusted High Availability Systems
We consider the problem of providing trusted computing functionality in high availability systems. We consider the case where data is required to be encrypted with a TPM protected key. For redundancy, and to facilitate high availability, the same TPM key is stored in multiple computational units, each one ready to take over if the main unit breaks down. This requires the TPM key to be migratable. We show how such systems can be realized using the secure storage of the TPM. Hundreds of millions TPM 1.2 chips have been shipped but with the recent introduction of TPM 2.0, more manufacturers are expected to start shipping this newer TPM. Thus, a migration from TPM 1.2 to TPM 2.0 will likely be seen in the next few years. To address this issue, we also provide an API that allows a smooth upgrade from TPM 1.2 to TPM 2.0 without having to redesign the communication protocol involving the dierent entities. The API has been implemented for both TPM 1.2 and TPM 2.0
eavesROP: Listening for ROP Payloads in Data Streams (preliminary full version)
We consider the problem of detecting exploits based on return-oriented programming. In contrast to previous works we investigate to which extent we can detect ROP payloads by only analysing streaming data, i.e., we do not assume any modifications to the target machine, its kernel or its libraries. Neither do we attempt to execute any potentially malicious code in order to determine if it is an attack. While such a scenario has its limitations, we show that using a layered approach with a filtering mechanism together with the Fast Fourier Transform, it is possible to detect ROP payloads even in the presence of noise and assuming that the target system employs ASLR. Our approach, denoted eavesROP, thus provides a very lightweight and easily deployable mitigation against certain ROP attacks. It also provides the added merit of detecting the presence of a brute-force attack on ASLR since library base addresses are not assumed to be known by eavesROP
'Triple wins' or 'triple faults'? Analysing policy discourse on climate-smart agriculture (CSA)
This paper aims to unpack the equity implications of âclimate-smart agricultureâ (CSA). The
CSA approach has gained considerable traction in recent years, but remains highly contested.
One of the principal areas of contestation relates to CSAâs contribution to social equity, yet
equity is rarely defined in the CSA literature. To fill this gap, we apply an equity framework
to four discourses that are commonly encountered in debates on the challenges and
opportunities for applying CSA in different contexts and for different purposes. From this, we
identify three important equity issues: First, distributive equity implies a need to acknowledge
how CSA may transfer the burden of responsibility for climate change mitigation to
marginalized producers and resource managers. Second, a procedural equity perspective
reveals how CSA discourses generally fail to confront entrenched power relations that may
constrain or block the emergence of more âpro-poorâ forms of agricultural development,
adaptation to climate change, or carbon sequestration and storage. Third, to improve CSA
outcomes, a focus on contextual equity means the need to pay more attention to the
institutions that underpin the bargaining power of the poorest and most vulnerable groups, as
well as a deeper acknowledgement of the political nature of transformations that are needed to
address challenges around the agricultural sector in a changing climate
Prosessorientering ved universiteter i Norge En fler-casestudie av erfaringer ved tre norske universiteter
Masteroppgave informasjonssystemer- Universitetet i Agder, 2015Kommunal- og moderniseringsminister Jan Tore Sanner har uttalt at regjeringen vil fjerne tidstyver i offentlig sektor. Universitet er en type organisasjoner i offentlig sektor som har interesse av Ä eliminere tidstyver. Prosessorientering er en styringsdisiplin som ved Ä fokusere pÄ prosesser fremfor funksjonelle og hierarkiske strukturer, muliggjÞr blant annet Þkt effektivitet og Þkt kvalitet. Det er utfÞrt lite forskning pÄ prosessorientering ved universiteter. Hensikten med vÄr masteroppgave er derfor Ä frembringe forstÄelse og ny innsikt i hvilke effekter norske universiteter kan oppnÄ ved Ä innfÞre prosessorientering.
Dette er en utforskende, kvalitativ fler-casestudie basert pÄ et fortolkende forskningsperspektiv. Vi har gjennom semi-strukturerte intervjuer samlet inn data om prosessorienteringstiltak ved tre norske universiteter. De tre universitetene er Universitetet i Nordland, Universitetet i Agder og Universitetet i TromsÞ.
VÄre funn indikerer at effekter av prosessorientering som er identifisert i tidligere litteratur, i stor grad gjelder for norske universiteter. Vi har videre identifisert to nye effekter av prosessorientering som ikke er omtalt i tidligere litteratur. Disse effektene er mer tid til de rette tingene og redusert sÄrbarhet i prosesser. Mer tid til de rette tingene innebÊrer at ressurser kan frigjÞres og tilfÞres undervisning og forskning, hvilket bidrar til at universitetene i stÞrre grad kan oppfylle sin samfunnsoppgave. Redusert sÄrbarhet i prosesser innebÊrer at universitetene i mindre grad er avhengige av nÞkkelpersoner for Ä gjennomfÞre sine prosesser. Det tredje funnet er at universitetene som deltok i studien ikke har utnyttet mulighetsrommet ved Ä bruke informasjonsteknologi for Ä understÞtte arbeidet med Ä forbedre prosesser.
Det kan anses som en begrensning i studien at to av tre case er fra universiteter som kun har arbeidet med Ă„ bli prosessorientert i en kort periode. Det kan tenkes at de identifiserte effektene av prosessorientering ikke nĂždvendigvis er sammenlignbare med universitetet som har arbeidet med prosessorientering i lengre tid. Videre kan det anses som en potensiell begrensning at respondentene som ble intervjuet i stor grad ble valgt av personer som jobber med prosessorienteringstiltakene ved de tre universitetene.
Gjennom litteratursÞk har vi ikke vÊrt i stand til Ä finne forskning som omhandler prosessorientering ved norske universiteter. VÄr studie bidrar til Ä utvide kunnskapsbasen pÄ et fenomen hvor det tidligere ikke er utfÞrt mye forskning. Videre belyser vi viktigheten av prosessorientering, og at prosessorientering kan vÊre like aktuelt og relevant for norske universiteter som virksomheter i privat sektor
âTriple winsâ or âtriple faultsâ? Analysing the equity implications of policy discourses on climate-smart agriculture (CSA)
This paper analyses contrasting discourses of âclimate-smart agricultureâ (CSA) for their implications on control over and access to changing resources in agriculture. One of the principal areas of contestation around CSA relates to equity, including who wins and who loses, who is able to participate, and whose knowledge and perspectives count in the process. Yet to date, the equity implications of CSA remain an under-researched area. We apply an equity framework centred on procedure, distribution and recognition, to four different discourses. Depending on which discourses are mobilised, the analysis helps to illuminate: (1) how CSA may transfer the burden of responsibility for climate change mitigation to marginalised producers and resource managers (distributive equity); (2) how CSA discourses generally fail to confront entrenched power relations that may constrain or block the emergence of more âpro-poorâ forms of agricultural development, adaptation to climate change, or carbon sequestration and storage (procedural equity); (3) how CSA discourses can have tangible implications for the bargaining power of the poorest and most vulnerable groups (recognition). The paper contributes to work showing the need for deeper acknowledgement of the political nature of the transformations necessary to address the challenges caused by a changing climate for the agricultural sector
The societal costs of dementia in Sweden 2012 â relevance and methodological challenges in valuing informal care
FörbÀttring av lagerhantering : Case: Oy Flexo-Power Ab
Detta examensarbete gjordes pÄ bestÀllning av Oy Flexo-Power Ab. Företaget Àr grun-dat 1994 och har en omsÀttning pÄ 2 miljoner euro, personalen bestÄr av 6 personer. Syf-tet med arbetet var att utreda vilka fördelar ett företag inom en teknisk bransch kan uppnÄ vid uppdatering av sitt lagerhanteringssystem. Företaget Flexo-Power Àr en Äter-försÀljare av smÄmaskiner och till alla maskiner de sÀljer erbjuder de ocksÄ service samt reservdelar. DÄ det finns omkring 5000 olika reservdelar i lagret krÀver det ett fungerande lagerhanteringssystem. Ett bra lagerhanteringssystem skall ha reda pÄ vad som finns i lager, var i lagret och i vilket lager produkterna finns. Systemet bör meddela nÀr en produkt börjar vara slut i lagret och dessutom eventuellt automatiskt bestÀlla pÄfyll-ning. Företaget har anvÀnt sig av manuella Excel-tabeller för att ha koll pÄ vad som finns i lagret. Problemet med de manuella Excel-tabellerna var att de inte uppdaterades tillrÀckligt ofta och informationen var dÀrför inte tillförlitlig. Företaget bestÀmde sig för att ta i bruk KoneFutur, ett specialverktyg för smÄmaskinsbranschen. Ibruktagningen av KoneFutur krÀvde att företagets datorer samt betalkortavlÀsarna uppdaterades, efter det kunde mjukvaran installeras och en utbildnings-dag pÄbörjas. För att sedan koppla systemet till lagret var det viktigt att börja gÄ igenom lagret och mata in produktkoderna till KoneFutur. En stor del av produkterna kommer utan nÄgon streckkod, vilket innebÀr att alla produkter skulle förses med streckkoder för att förenkla samt effektivisera för-sÀljningen. KoneFutur togs i bruk under vÄren 2017 och har nu varit i anvÀndning ett Är. För att komma fram till resultatet om vilka fördelar företaget har uppnÄtt vid uppdateringen av lagerhanteringssystemet har kvalitativa intervjuer anvÀnts. Resultaten var positiva, de tvÄ respondenterna vid intervjuerna Àr de tvÄ försÀljare som startat företaget. Det att man nu vet vad man har i lagret och hur mÄnga exemplar var den huvudsakliga förbÀttringen som uppdateringen medförde
Mining peasants and pig-iron merchants. Perspectives om industrialization 1810 - 1900
This thesis studies the preconditions for the industrialization of the Swedish iron industry in Lekebergslagen in the county of NĂ€rke. It focuses on the Bergsman and the ironworks, and on the division of production between these two, which was imposed by the government from the 17th century onto the early 19th century. The Bergsman and his household were mining peasants. They had special privileges, for example the mining peasants had exclusive property rights to their land during a long period of time. In return they had to produce pig-iron for the Swedish state. The pig-iron was transformed into bar-iron at the ironworks. By the year of 1810 the mining peasants lost these exclusive property rights. The purpose of this study is to analyze the consequences of this development. Which were the consequences of the land reform for the traditional division of production between the ironworks and the mining peasants? Two concepts central to this study are economic stratification and penetration. These concepts were previously discussed in the research of the Western European proto-industrialization. The researchers considered the industrialization a long process where groups of capitalists and a proletariat evolved through socio-economic stratification, and the small-scale commodity production was penetrated by the capitalists, who finally transferred all production into factories. In conjunction, those two processes constituted the foundation for the industrial breakthrough. Previous research often studies one of these three aspects, but this thesis studies the relationship between penetration, differentiation and industrialization.
The iron industry gradually evolved during the 19th century, and by the end of the century it was centralized, that is, industrialized. This study shows that the industrialization process was far from linear. The industrialization of the iron production in Lekebergslagen was preceded by complicated interaction between several operators as well as between different types of capital. The mining peasants of Lekebergslagen were gradually involved in a production system that was mainly controlled by others because of a credit system. The mining peasants in Lekebergslagen were exploited by local creditors within or linked to the mining peasant community, or by the ironworks. A group of capitalists eventually appeared in the local society. We might even say that the mining peasants in Lekebergslagen were gradually proletarianized during the first half of the 19th century. This proletariat was not set free until the mortgage banks were established in the mid 19th century, and when the iron production was centralized. The mining peasants then got the opportunity to emancipate from the local usurers and to invest in agriculture instead of iron production; in the eyes of the ironworks, exploitation of the mining peasants was no longer the most cost-efficient production solution
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