28 resultados para IPv6, Denial of Service, Coloured Petri Nets, Risk Analysis, IPv6threats
em Doria (National Library of Finland DSpace Services) - National Library of Finland, Finland
Resumo:
This thesis studies techniques used for detection of distributed denial of service attacks which during last decade became one of the most serious network security threats. To evaluate different detection algorithms and further improve them we need to test their performance under conditions as close to real-life situations as possible. Currently the only feasible solution for large-scale tests is the simulated environment. The thesis describes implementation of recursive non-parametric CUSUM algorithm for detection of distributed denial of service attacks in ns-2 network simulator – a standard de-facto for network simulation.
Resumo:
Palvelukehitystoiminta sitoo huomattavan määrän resursseja ja on pitkäkestoista toimintaa. Innovatiivisuuteen tähtäämällä ja systemaattisella tuotekehitystyöllä yritys parantaa jatkuvuutta omassa liiketoiminnassaan. Alusta-ajattelu tuo uuden ulottuvuuden tuotteiden ja palveluiden kehitykseen. Alustan kehittäminen tukemaan tuote- ja palvelukehitystoimintaa ja yksinkertaistamaan tuote/palvelurakenteita antaa yrityksissä lisäpotentiaalia esimerkiksi lyhentyneiden kehitysaikojen, paremman kompleksisuuden hallinnan ja kustannustehokkuuden nousun myötä. Toimintojen tehostuminen yritystasolla saa aikaan mahdollisuuksien lisääntymisen nykyisillä liiketoimintasektoreilla. Palvelualustan kehityksellä päästään palvelurakenteen mallintamisen kautta parempaan liiketoiminnan hallitsemiseen ja systemaattisempaan tuotekehityksen läpivientiin. Palvelualustan yhtenä tärkeimpänä hyötynä on, että palvelun rakenteellisuus saadaan kuvattua alustaan. Lisäksi on tärkeää määritellä vastuutukset alustan kehityksessä, sekä pystyä mallintamaan informaation kulku (rajapinnat) prosesseissa.
Resumo:
Diplomityössä tarkastellaan palveluoperaattoreiden asemaa Länsi-Euroopan matkapuhelinpalvelumarkkinoilla. Tavoitteena on selvittää, ovatko palveluoperaattorit potentiaalisia asiakkaita tietylle matkapuhelinlisäpalvelujärjestelmien toimittajalle. Lisäksi tavoitteena on rakentaa liiketoimintalaskelmatyökalu, jolla tällaisen järjestelmäinvestoinnin kannattavuus voidaan osoittaa paitsi palveluoperaattorille, myös tämän loppuasiakkaille. Työ aloitetaan matkapuhelinpalvelumarkkinoilla toimivien osapuolten esittelyllä. Eri osapuolten asemaa ja merkitystä matkapuhelinpalvelumarkkinoilla käsitellään. Matkapuhelinpalvelumarkkinoiden kehitystä tarkastellaan uuden teknologian ja erityisesti tulevien palvelujen näkökulmasta. Tarkastelua jatketaan analysoimalla regulaation vaikutusta matkapuhelinpalvelumarkkinoihin. Erityisesti kiinnitetään huomiota regulaation motiiveihin sekä käytännön toteutukseen tietyissä Länsi-Euroopan maissa. Tutkimuksen toteuttamisessa merkittävässä osassa ovat asiantuntijahaastattelut sekä markkina-analyysiraportit.Markkina-analyysissa saatuja tuloksia hyödynnetään liiketoimintalaskelmatyökalun toteutuksessa. Työn tuloksena päädytään myös ratkaisuun palveluoperaattoreiden kiinnostavuudesta asiakassegmenttinä. Tämän lisäksi havaitaan muita potentiaalisia asiakassegmenttejä, joiden tämäntyyppiseen liiketoimintaan soveltuvuutta tutkitaan edelleen.
Resumo:
Tässä työssä on esitetty sen ohjelmiston kehittämisen prosessi, joka on tarkoitettu annettavien palveluiden valvottavaksi käyttäen prototyyppimallia. Raportti sisältää vaatimusten, kohteisiin suunnatun analyysin ja suunnittelun, realisointiprosessien kuvauksen ja prototyypin testauksen. Ohjelmiston käyttöala – antavien palveluiden valvonta. Vaatimukset sovellukselle analysoitiin ohjelmistomarkkinoiden perusteella sekä ohjelmiston engineeringin periaatteiden mukaisesti. Ohjelmiston prototyyppi on realisoitu käyttäen asiakas-/palvelinhybridimallia sekä ralaatiokantaa. Kehitetty ohjelmisto on tarkoitettu venäläisille tietokonekerhoille, jotka erikoistuvat pelipalvelinten antamiseen.
Resumo:
IP-verkkojen hyvin tunnettu haitta on, että nämä eivät pysty takaamaan tiettyä palvelunlaatua (Quality of Service) lähetetyille paketeille. Seuraavat kaksi tekniikkaa pidetään lupaavimpina palvelunlaadun tarjoamiselle: Differentiated Services (DiffServ) ja palvelunlaatureititys (QoS Routing). DiffServ on varsin uusi IETF:n määrittelemä Internetille tarkoitettu palvelunlaatumekanismi. DiffServ tarjoaa skaalattavaa palvelujen erilaistamista ilman viestintää joka hypyssä ja per-flow –tilan ohjausta. DiffServ on hyvä esimerkki hajautetusta verkkosuunnittelusta. Tämän palvelutasomekanismin tavoite on viestintäjärjestelmien suunnittelun yksinkertaistaminen. Verkkosolmu voidaan rakentaa pienestä hyvin määritellystä rakennuspalikoiden joukosta. Palvelunlaatureititys on reititysmekanismi, jolla liikennereittejä määritellään verkon käytettävissä olevien resurssien pohjalta. Tässä työssä selvitetään uusi palvelunlaatureititystapa, jota kutsutaan yksinkertaiseksi monitiereititykseksi (Simple Multipath Routing). Tämän työn tarkoitus on suunnitella palvelunlaatuohjain DiffServille. Tässä työssä ehdotettu palvelunlaatuohjain on pyrkimys yhdistää DiffServ ja palvelunlaatureititysmekanismeja. Työn kokeellinen osuus keskittyy erityisesti palvelunlaatureititysalgoritmeihin.
Resumo:
In this thesis I examine Service Oriented Architecture (SOA) considering both its positive and negative qualities for business organizations and IT. In SOA, services are loosely coupled and invoked through standard interfaces to enable business process independence from the underlying technology. As an architecture, SOA brings the key benefit of service reuse that may mean anything from simple application reuse to taking advantage of entire business processes across enterprises. SOA also promises interoperability especially by the Web services standards that enable platform independency. Cost efficiency is mainly a result of the savings in IT maintenance and reduced development costs. The most severe limitations of SOA are performance implications and security issues, but the applicability of SOA is also limited. Additional disadvantages of a service oriented approach include problems in data management and complexity questions, and the lack of agreement about SOA and its twofold nature as a business as well as technology approach leads to problematic interpretation of the available information. In this thesis I find the benefits and limitations of SOA for the purpose described above and propose that companies need to consider the decision to implement SOA carefully to determine whether the benefits will outdo the costs in the individual case.
Resumo:
The objective of this study has been to make a profitability analysis of service contracts for a company in Finland. The purpose has been to see how profitable the contracts are and if there possibly were some things to change or develop in the contracts. Allocation rules of cost accounting, service costs both profitability and management of services have been considered in the theory part. All the service contracts that have been valid at least three last accounting periods have been included in the study. All direct costs relating to the contracts have been collected and indirect costs have been assigned to the contracts. Profitability of the contracts has been calculated over three years. Results have been analyzed according to the key figures the company is controlling. Some suggestions for developments have been given at the end of the study. The study has shown differences between the contracts. Part of them has turned out to be like the profitability aims of the company and part less profitable. The study has shown that many factors have an effect on the profitability of the service contracts.
Resumo:
The increasing incidence of type 1 diabetes has led researchers on a quest to find the reason behind this phenomenon. The rate of increase is too great to be caused simply by changes in the genetic component, and many environmental factors are under investigation for their possible contribution. These studies require, however, the participation of those individuals most likely to develop the disease, and the approach chosen by many is to screen vast populations to find persons with increased genetic risk factors. The participating individuals are then followed for signs of disease development, and their exposure to suspected environmental factors is studied. The main purpose of this study was to find a suitable tool for easy and inexpensive screening of certain genetic risk markers for type 1 diabetes. The method should be applicable to using whole blood dried on sample collection cards as sample material, since the shipping and storage of samples in this format is preferred. However, the screening of vast sample libraries of extracted genomic DNA should also be possible, if such a need should arise, for example, when studying the effect of newly discovered genetic risk markers. The method developed in this study is based on homogeneous assay chemistry and an asymmetrical polymerase chain reaction (PCR). The generated singlestranded PCR product is probed by lanthanide-labelled, LNA (locked nucleic acid)-spiked, short oligonucleotides with exact complementary sequences. In the case of a perfect match, the probe is hybridised to the product. However, if even a single nucleotide difference occurs, the probe is bound instead of the PCR product to a complementary quencher-oligonucleotide labelled with a dabcyl-moiety, causing the signal of the lanthanide label to be quenched. The method was applied to the screening of the well-known type 1 diabetes risk alleles of the HLA-DQB1 gene. The method was shown to be suitable as an initial screening step including thousands of samples in the scheme used in the TEDDY (The Environmental Determinants of Diabetes in the Young) study to identify those individuals at increased genetic risk. The method was further developed into dry-reagent form to allow an even simpler approach to screening. The reagents needed in the assay were in dry format in the reaction vessel, and performing the assay required only the addition of the sample and, if necessary, water to rehydrate the reagents. This allows the assay to be successfully executed even by a person with minimal laboratory experience.
Resumo:
The main objective of this study is to examine the relationships between resources, competitive advantage and firm success. The study focuses, on one hand, on the financial performance of service-intensive manufac-turing firms against competitors with a lower service intensity and, on the other hand, on the resources as drivers for competitive advantage and success. The purpose of the theoretical part is to link the study in the field of the strategy research. The empirical part of the study is based on the quantitative analyses of the survey data collected from 50 major suppliers of industrial machinery and transportation equipment in Europe and North America. Results indicate that service-intensive manufacturing firms have performed better and their performance has been more stable vis-à-vis their peers. The main resources that differentiate service-intensive manufacturing firms from their non-service intensive competitors are service strategy and service-oriented top management. The analyses on the VRIO resources produced only a limited amount of information and solely service-centred culture appeared to be a rent generating resource.
Resumo:
Background: Atherosclerosis begins in early life progressing from asymptomatic to symptomatic as we age. Although substantial progress has been made in identifying the determinants of atherosclerosis in middle to older age adults at increased cardiovascular risk, there is lack of data examining determinants and prediction of atherosclerosis in young adults. Aims: The current study was designed to investigate levels of cardiovascular risk factors in young adults, subclinical measures of atherosclerosis, and prediction of subclinical arterial changes with conventional risk factor measures and novel metabolic profiling of serum samples. Subjects and Methods: This thesis utilised data from the follow-ups performed in 2001 and 2007 in the Cardiovascular Risk in Young Finns study, a Finnish population-based prospective cohort study that examined 2,204 subjects who were aged 30-45 years in 2007. Subclinical atherosclerosis was studied using noninvasive ultrasound measurements of carotid intima-media thickness (IMT), carotid arterial distensibility (CDist) and brachial flow-mediated dilation (FMD). Measurements included conventional risk factors and metabolic profiling using highthroughput nuclear magnetic resonance (NMR) methods that provided data on 42 lipid markers and 16 circulating metabolites. Results: Trends in lipids were favourable between 2001 and 2007, whereas waist circumference, fasting glucose, and blood pressure levels increased. To study the stability of noninvasive ultrasound markers, 6-year tracking (the likelihood to maintain the original fractile over time) in 6 years was examined. IMT tracked more strongly than CDist and FMD. Cardiovascular risk scores (Framingham, SCORE, Finrisk, Reynolds and PROCAM) predicted subclinical atherosclerosis equally. Lipoprotein subclass testing did not improve the prediction of subclinical atherosclerosis over and above conventional risk factors. However, circulating metabolites improved risk stratification. Tyrosine and docosahexaenoic acid were found to be novel biomarkers of high IMT. Conclusions: Prediction of cardiovascular risk in young Finnish adults can be performed with any of the existing risk scores. The addition of metabonomics to risk stratification improves prediction of subclinical changes and enables more accurate targeting of prevention at an early stage.
Resumo:
Tässä diplomityössä tehtiin Olkiluodon ydinvoimalaitoksella sijaitsevan käytetyn ydinpolttoaineen allasvarastointiin perustuvan välivaraston todennäköisyysperustainen ulkoisten uhkien riskianalyysi. Todennäköisyysperustainen riskianalyysi (PRA) on yleisesti käytetty riskien tunnistus- ja lähestymistapa ydinvoimalaitoksella. Työn tarkoituksena oli laatia täysin uusi ulkoisten uhkien PRA-analyysi, koska Suomessa ei ole aiemmin tehty vastaavanlaisia tämän tutkimusalueen riskitarkasteluja. Riskitarkastelun motiivina ovat myös maailmalla tapahtuneiden luonnonkatastrofien vuoksi korostunut ulkoisten uhkien rooli käytetyn ydinpolttoaineen välivarastoinnin turvallisuudessa. PRA analyysin rakenne pohjautui tutkimuksen alussa luotuun metodologiaan. Analyysi perustuu mahdollisten ulkoisten uhkien tunnistamiseen pois lukien ihmisen aikaansaamat tahalliset vahingot. Tunnistettujen ulkoisten uhkien esiintymistaajuuksien ja vahingoittamispotentiaalin perusteella ulkoiset uhat joko karsittiin pois tutkimuksessa määriteltyjen karsintakriteerien avulla tai analysoitiin tarkemmin. Tutkimustulosten perusteella voitiin todeta, että tiedot hyvin harvoin tapahtuvista ulkoisista uhista ovat epätäydellisiä. Suurinta osaa näistä hyvin harvoin tapahtuvista ulkoisista uhista ei ole koskaan esiintynyt eikä todennäköisesti koskaan tule esiintymään Olkiluodon vaikutusalueella tai edes Suomessa. Esimerkiksi salaman iskujen ja öljyaltistuksen roolit ja vaikutukset erilaisten komponenttien käytettävyyteen ovat epävarmasti tunnettuja. Tutkimuksen tuloksia voidaan pitää kokonaisuudessaan merkittävinä, koska niiden perusteella voidaan osoittaa ne ulkoiset uhat, joiden vaikutuksia olisi syytä tutkia tarkemmin. Yksityiskohtaisempi tietoisuus hyvin harvoin esiintyvistä ulkoisista uhista tarkentaisi alkutapahtumataajuuksien estimaatteja.
Resumo:
The main objective of this Master’s Thesis was to examine the interrelations of service quality and relationship quality (customer satisfaction, trust and commitment), and find out are they antecedents for customer loyalty in business-to-business context. Literature review revealed some research gaps concerning these focal concepts, which should be studied more closely. The theoretical basis for this research was collected for evaluating a strategic increase of customer’s perceptions of service quality and relationship quality as well as customer loyalty in business-to-business environment, and it was tested empirically in a sample of 164 corporate customers, who responded to the Internet-based survey. The measures, used in the survey, were first assessed by using confirmatory factor analysis (CFA), and then the hypothesized relationships were further verified using structural equation modeling (SEM) in LISREL 8.80. There was found support for a half of the hypothesized construct relations. The results of the research confirm the direct influence of trust and commitment on customer loyalty. Also, service quality turned out to have an indirect impact on customer loyalty through trust. No support, however, was offered for the proposed impact of customer satisfaction on loyalty in this case. The research provides managerially relevant and actionable results that may help service providers execute more specific customer relationship quality strategies that lead to higher customer loyalty.
Resumo:
The intent of this research was to develop a model that describes the extent to which customer behavioral intentions are influenced by service quality, customer satisfaction and customer perceived value in the business-to-business service context. Research on customer behavioral intentions is quite fragmented and no generalized model has been presented. Thus, there was need for empirical testing. This study builds on the services marketing theory and assesses the relationships between the identified constructs. The data for the empirical analysis was collected via a quantitative online survey and a total of 226 usable responses were obtained for further analysis. The model was tested in an employment agency service setting. The measures used in this survey were first assessed by using confirmatory factor analysis (CFA) after which the hypothesized relationships were further verified using structural equation modeling (SEM) in LISREL 8.80. The analysis identified that customer satisfaction played a pivotal role in the model as it was the only direct antecedent of customer behavioral intentions, however, customer perceived value showed a strong indirect impact on buying intentions via customer satisfaction. In contrast to what was hypothesized, service quality and customer perceived value did not have a direct positive effect on behavioral intentions. Also, a contradicting finding with current literature was that sacrifice was argued to have a direct but positive impact on customer perceived value. Based on the findings in this study, managers should carefully think of their service strategies that lead to their customers’ favorable behavioral intentions.
Resumo:
The aim of this Master’s thesis was to study the antecedents of customer satisfaction and behavioral intentions and their relative relationships in the sports sponsorship context. The possible antecedents under investigation in the current research are service value and service quality. As the academic background in the sports sponsorship literature is still rather modest there was a need for further empirical testing. The theoretical part of the research builds on the existing services marketing literature with sports sponsorship and business-to-business contexts in mind. The empirical study focused on the case company Liiga-SaiPa Oy. The data for the empirical analysis was collected via quantitative online survey. The total sample consisted of 357 the case company’s business customers and a total of 80 usable responses were collected. The data was analyzed by using statistical analysis software, SPSS. According to the results of the empirical analysis the most important antecedent of behavioral intentions in the underlying context is customer satisfaction. Also service value was found to have a direct and positive relationship with behavioral intentions. Moreover no indirect relationships through satisfaction were found between service quality and service value and behavioral intentions. However both constructs of service value and service quality were diagnosed to have a direct and positive effect on customer satisfaction. Service quality was also found to be a direct antecedent of service value with other service value benefits. However a contradicting finding with the current literature was, that service value sacrifices were not found to have a significant relationship with overall service value perceptions.