This thesis is focus on problematics of nodes localization in Internet. There are describe methods for prediction latency by using artificial coordinates systems and by using direct measurement. This thesis is primarily focus on method names King, which is estimates latency between arbitrary end hosts by using recursive DNS queries in system for translate domain name.

This thesis covers the topic of determination of geographical location of a host in internet network while utilizing measurement of the end to end delay and implementation of Constraint-Based Geolocation. Gradually I go through issue of the delay in computer networks and ways how to measure it. Next chapter describes a few ways to geolocate host in internet network with emphasis on the CBG method. Another chapter is dedicated to describing a way to project spherical coordinates to the two dimensional space, which has been used in implementation of geolocation method. Chapter about implementation builds upon the facts given in previous chapters while functions of the program written in the JAVA programing language are being explained. Two similar geolocation methods were implemented. By comparing the results gained by implementation, new method of geolocation is proposed and devised. It combines properities of both previous methods. There are results of the implemented methods and their comparation to the one of the source documents used in creation of this thesis in summary section.

This thesis deals with predicting the latency between two network nodes, such as the two stations, two servers or server and station. The main reason for adoption of effective latency prediction techniques is the elimination of network load caused by unnecessary repeated transmissios or by direct measurement of the latency. Of the many proposed methods of latency estimation, this thesis is focused on methods using artificial coordinate systems with primary focus on the Vivaldi algorithm. Characteristics of the latency prediction methods and properties of various coordinate systems used in practice are evaluated. The issue of the number of dimensions of space defined only by the latency matrix between nodes is also mentioned. Furthermore, some other systems, based on logical clustering of nearby nodes, are mentioned. Description of simulation software VivaldiMonitor developed as part of the thesis is included. The primary purpose is analysis of the behavior of overlay networks implementing Vivaldi algorithm with less than a few hundred nodes. The Vivaldi algorithm is assessed by several simulations carried out using the aforementioned software.

In this master thesis project, a new protocol called the Round Trip Time (RTT) protocol is implemented and verified. It helps determine the Ethernet clock frequency offset between two communicating nodes. The detection of this offset between nodes is a way to reduce the clock synchronization error. Ethernet is the basis on which a large amount of communication takes place in the world. Either it is used for exchanging data from one device to another or to connect devices to the internet. Due to the absence of clocks being exchanged between the various Ethernet communicating nodes, clock phase and frequency offsets can be present which leads to clock de-synchronization between the various nodes and results in lower system throughput. In the telecommunication industry, synchronization error between base stations can lead to lower throughput, performance degradation and packet loss. Also, with the introduction of 5G, stringent requirements will be placed on the clock synchronization errors.Currently, the Precision Time Protocol (PTP) is used to detect and correct clock synchronization errors. The PTP implementation reduces the clock synchronization error but it is still quite large. Hence, it is necessary to find a protocol which can work together with the PTP protocol to reduce this error. This thesis will introduce a new way to determine the clock frequency offset between nodes through the implementation of the RTT protocol. Through the course of this project, the clock frequency offset was determined by the RTT protocol. By comparing the expected and the theoretical clock offsets, it was concluded that the two values were very similar. The error between the offsets was in the range of 2.349-15.687 parts per billion (ppb) of the link frequency. Thus, the RTT protocol accurately and precisely determined the clock frequency offset between two Ethernet communicating nodes. This protocol is also extended to determine the clock frequency offset between two nodes transmitting periodic signals. For future works, this protocol can be combined with the PTP protocol and a way to determine the clock phase offset will be investigated. / I detta examensarbete implementerades och verifierades ett nytt protokoll, kallat Round Trip Time (RTT)-protokollet, som hjälper till att bestämma Ethernets klockfrekvensförskjutning mellan två kommunicerande noder. Denna fastställda förskjutning mellan de två noderna är ett sätt att reducera klocksynkroniseringsfelet. Ethernet är grunden i en stor del av dagens kommunikation i världen. Antingen används det för informationsutbyte mellan två enheter, eller för att ansluta till internet. Då det saknas ett utbyte av referensklocka mellan de olika kommunikationsnoderna på Ethernet, kan det uppstå klockfasoch frekvensförskjutning som leder till att klockan desynkroniseras mellan de olika noderna och därmed ger ett minskat dataflöde. I telekommunikationsindustrin kan ett synkronisationsfel mellan basstationer leda till minskat dataflöde, sämre prestanda och paketförlust. I och med introduktionen av 5G kommer stränga krav att ställas på klocksynkronisationsfelen.För närvarande används Precision Time Protocol (PTP) för att upptäcka och korrigera klocksynkroniseringsfelen. Implementationen av PTP reducerar klocksynkroniseringsfelet, men det är fortfarande relativt stort. Därav är det nödvändigt att hitta ett protokoll som kan arbeta tillsammans med PTP för att reducera detta fel. Detta arbete kommer att introducera ett nytt sätt att bestämma klockfrekvensförskjutningen genom implementation av RTT-protokollet. I detta arbete bestämdes klockfrekvensförskjutningen av RTT-protokollet. Genom att jämföra det förväntade och faktiska värdet på klockförskjutningen kunde slutsatsen dras att de två värdena var väldigt lika. Felet var i storleksordningen av 2,349-15,687 parts per billion (ppb) i linkfrekvensen. Således bestämmer RTT-protokollet korrekt och exakt klockfrekvensförskjutningen mellan de två kommunikationsnoderna i Ethernet. Protokollet utökas också för att bestämma klockfrekvensförskjutningen mellan två noder som sänder en periodisk signal. För framtida arbete kan detta protokoll kombineras med PTP-protokollet, och det ska även undersökas ett sätt för att bestämma klockfasförskjutningen.

This thesis is dedicated to measuring the communication performance of LoRa technology in an indoor environment and providing insight into its potential application as an effective Internet of Things (IoT) communication solution in Low Power Wide Area Networks (LPWAN). Through careful experimentation and analysis, we assessed various transmission parameters such as spreading factor (SF), bandwidth (BW), Payload Length (PL), and LoRaWAN classes. Performance metrics including Receive Signal Strength Indicator (RSSI), Signal-to-Noise Ratio (SNR), Round-trip time (RTT), and Goodput are measured to evaluate LoRa’s performance under different settings. The research question addressed is whether LoRa can be effectively used for indoor wireless communication. Our findings demonstrate that LoRa technology exhibits good transmission range, reliability, and cost-effectiveness in indoor environments, making it suitable for some indoor IoT applications. We also examined the impact of different LoRaWAN device classes and highlighted the importance of balancing the SF and BW to optimize communication performance. In conclusion, this thesis offers a comprehensive understanding of the communication performance of LoRa technology in indoor environments, providing valuable guidance for its practical application in indoor IoT communication. The research findings presented herein serve as a significant reference for future research endeavors in this field, enabling further advancements in the domain of LoRa-based wireless communication technologies for indoor IoT applications. / Denna avhandling ägnas åt att mäta kommunikationsprestanda för LoRa-teknik i en inomhusmiljö och ger insikt i dess potentiella tillämpning som en effektiv kommunikationslösning för Internet of Things (IoT) i Low Power Wide Area Networks (LPWAN). Genom noggranna experiment och analys utvärderade vi olika överföringsparametrar som spridningsfaktor (SF), bandbredd (BW), nyttolastlängd och LoRaWAN-enhetens klasser. Prestandametriker inklusive Receive Signal Strength Indicator (RSSI), Signal-to-Noise Ratio (SNR), Round-trip time (RTT) och Goodput mäts för att utvärdera LoRa’s prestanda under olika inställningar. Forskningsfrågan som behandlas är om LoRa effektivt kan användas för inomhus trådlös kommunikation. Våra resultat visar att LoRa-teknik uppvisar bra överföringsområde, tillförlitlighet och kostnadseffektivitet i inomhusmiljöer, vilket gör det lämpligt för vissa inomhus-IoT-applikationer. Vi undersökte också inverkan av olika LoRaWAN-enhet klasser och framhävde vikten av att balansera SF och BW för att optimera kommunikationsprestanda. Sammanfattningsvis erbjuder denna avhandling en omfattande förståelse för kommunikationsprestanda för LoRa-teknik i inomhusmiljöer, vilket ger värdefull vägledning för dess praktiska tillämpning inom inomhus IoT-kommunikation. De forskningsresultat som presenteras här fungerar som en betydande referens för framtida forskningsinsatser inom detta område, vilket möjliggör ytterligare framsteg inom området för LoRa-baserade trådlösa kommunikationstekniker för inomhus IoT-applikationer.

A edição da Lei nº 11.638/07, responsável por dar início ao processo de convergência das normas brasileiras de contabilidade ao padrão contábil internacional, hoje ditado pelo International Accounting Standards Board (IASB), trouxe consigo uma série de dúvidas acerca de seus possíveis reflexos tributários. É que, dada a profunda relação existente entre o Direito Tributário e a Contabilidade, não se pode ignorar o potencial que mudanças ocorridas nessa última têm de gerar impactos na esfera tributária. Se isso ocorreu (ou não) e quais os seus limites é o que o presente trabalho se propôs a investigar. Entretanto, em primeiro lugar é preciso que se compreenda o contexto em que a referida lei foi editada. Sua publicação foi precedida de intenso debate, principalmente no âmbito do mercado de valores mobiliários, uma vez que as empresas brasileiras listadas em bolsas de valores foram as primeiras a sentir os efeitos das diferenças entre o padrão contábil brasileiro e o padrão internacional. No âmbito acadêmico, é inegável a contribuição dos professores e alunos da Faculdade de Economia e Administração da Universidade de São Paulo (FEAUSP), que há muito vinham notando a necessidade de o Brasil integrar o processo internacional de convergência das normas contábeis ao padrão International Financial Reporting Standards (IFRS). No que diz respeito aos participantes do mercado de valores mobiliários, o afastamento da contabilidade brasileira em relação ao padrão internacional prejudica a comparabilidade entre demonstrações financeiras elaboradas com base em modelos contábeis diversos, diminuindo, em última análise, o fluxo de recursos em um ambiente cada vez mais globalizado. Assim, a convergência traria apenas benefícios, na medida em que reduziria o custo do investimento ao eliminar os efeitos decorrentes da assimetria da informação contábil. Em relação à Ciência Contábil, a mudança também teria vindo em boa hora. Devido a uma série de fatores, grande parte deles tratada ao longo do trabalho, a contabilidade brasileira foi influenciada por uma visão bastante conservadora do patrimônio e suas mutações, muito mais próxima da perspectiva jurídico-fiscal. Com isso, as regras de contabilidade brasileira se afastaram dos princípios contábeis para irem ao encontro das normas relacionadas à apuração de tributos. Em poucas palavras, a Receita Federal do Brasil foi, durante as últimas décadas, o mais influente usuário da informação financeira. Dessa forma, sob uma ótica estritamente contábil, o início do processo de convergência ao padrão internacional foi visto como um grande avanço. A adoção da primazia da essência econômica sobre a forma jurídica, profundamente presente no padrão IFRS, representa a libertação da contabilidade brasileira das amarras impostas pela Receita Federal do Brasil (RFB). A ciência contábil fica liberada, de forma definitiva, para construir seus próprios princípios, sem a indesejada influência das autoridades administrativas. A Contabilidade volta a estar comprometida com a geração de informações para seus usuários, em conformidade com a realidade econômica, ainda que esta possa contrariar aquela construída pelo Direito. Note-se que até aqui nada se mencionou acerca dos aspectos tributários da Nova Contabilidade. Em verdade, essa preocupação fez parte das discussões que precederam a publicação da Lei nº 11.638/07, tanto que o art. 177 da Lei das Sociedades Anônimas foi alterado para prever que os lançamentos de ajuste efetuados exclusivamente para harmonização de normas contábeis [...] não poderão ser base de incidência de impostos e contribuições nem ter quaisquer outros efeitos tributários. O que se pretendeu, portanto, foi estabelecer que os eventuais efeitos tributários provenientes de mudanças oriundas do novo padrão contábil devessem ser neutralizados. No entanto, a simples previsão legal de neutralidade, muito embora nos indique a intenção do legislador no que diz respeitos aos aspectos tributários, não foi capaz de resolver todas as dúvidas que surgiram imediatamente após a publicação da Lei nº 11.638/07. Em maio de 2008, portanto, menos de seis meses após o início da vigência da Lei nº 11.638/07, a RFB se manifestou no sentido da tributação das subvenções para investimento (Solução de Consulta nº 75/2008). Era o prenúncio de que a referida neutralidade seria objeto de fortes discussões. Muito em razão disso foi promulgada a Medida Provisória nº 449/08, posteriormente convertida na Lei nº 11.941/09, que instituiu o Regime Tributário de Transição (RTT). Em linhas gerais, a regra de neutralidade anterior foi substituída por um regime mais detalhado, com a determinação de que as alterações decorrentes da Lei nº 11.638/07, que modifiquem o critério de reconhecimento de receitas, custos e despesas não terão efeitos para fins de apuração do lucro real da pessoa jurídica a ele submetido. É inegável que o RTT trouxe mais segurança no que diz respeito aos aspectos específicos da neutralidade. Por outro lado, não foi capaz de solucionar a integralidade das questões postas em discussão, o que pode ser verificado pelas inúmeras interpretações divergentes dadas a questões aparentemente simples, como o ágio baseado em expectativa de rentabilidade futura e a isenção sobre a distribuição de dividendos. Nesse contexto, o presente trabalho se propôs a investigar o problema desde a sua origem, identificando as razões históricas para a diversidade de padrões contábeis ao redor do mundo, a realidade brasileira e a relação entre o Direito Tributário e a Contabilidade no Brasil, para chegar à conclusão acerca da real influência do novo padrão contábil sobre a tributação. / The enactment of Law 11,638/07, which set out to converge Brazilian accounting regulations to those of the International Accounting Standards Board (IASB), has brought with it a series of issues regarding its possible tax reflections. Given the profound relationship that exists between Tax Law and Accounting, one cannot ignore the potential impact that the changes to the latter can have on taxation. This paper investigates whether or not that has occurred and, if so, to what extent. First, nonetheless, one must understand the context in which the aforementioned act was promulgated. Its enactment was preceded by intense debate, especially within the realm of the securities market, since all listed companies in Brazil were the first to feel the effects of the differences between the Brazilian accounting standards and the international accounting standards. In the academic arena, one cannot deny the contribution of professors and students of the School of Economics and Business Administration of São Paulo (FEA-USP), who had long envisioned the need for Brazils accounting standards to conform to the International Financial Reporting Standards (IFRS). Concerning the players in the securities market, the uniqueness of the Brazilian accounting standards against international standards impairs comparability among income statements based on diverse accounting models, ultimately decreasing the flow of investments in an increasingly globalized environment. Thus, convergence would be beneficial, insofar as it would reduce investment costs by eliminating the effects arising out of the asymmetry of the accounting information. As for the scientific aspect of accounting, the change has allegedly come in good time. Due to a series of factors, most of which are dealt with all through this paper, Brazilian accounting has been influenced by a very conservative view of assets and changes thereto, a view that is closest to the tax/legal perspective. As a result, Brazils accounting practices have thus far pushed aside accounting principles to meet tax appraisal rules. To put it shortly, the Brazilian Federal Revenue has been the most influential user of accounting information in the last few decades. Thus, from a pure accounting viewpoint, the beginning of the converging process can be seen as a major improvement. Prioritizing economic substance over legal form, as is the case with IFRS, will free Brazilian accounting from the ties imposed by the Brazilian Federal Revenue. The accounting sciences will be finally free to build its own principles, without the undesired influence of the administrative authorities. Accounting is once again committed to generating information to its users, in conformity with economic reality, even if the latter can conflict with that of the law. Notably, so far not a word has been mentioned with regard to the tax aspects of the New Accounting. In fact, this concern did make part of the discussions that preceded the enactment of Law 11,638/07, so much that section 177 of the Corporations Act has been altered to provide that adjustment entries made solely for the purpose of accounting harmonization (...) cannot be a tax base for any taxes or levies, nor are they subject to any other tax effects. The intention was to set forth that any tax effects arising out of the changes brought on by the new accounting standards were to be neutralized. Nonetheless, this mere statutory provision for neutrality was not capable of clearing up all the doubts that arose immediately after the enactment of Law 11,638/07, despite the legislators intent concerning the tax aspects. In May 2008, therefore, less than six months after Law 11,638/07 went into effect, the Brazilian Federal Revenue issued an opinion for the levy of taxation on investment aid (Advance Consultation n. 75/2008). That clearly indicated that the so-called neutrality would be the source of great battles. For this reason, Provisional Decree n. 449/08 was promulgated and later converted into Law n. 11,941/09, providing for the Transitional Tax Regime. In simple terms, the previous rule of neutrality was replaced by a more detailed regime, determining that the changes arising from Law n. 11,638/07, which modify the criteria to recognize revenue, costs and expenses, will not affect the appraisal of profits of a legal entity submitted to it. It is undeniable that the Transitional Tax Regime has brought more security with respect to the specific aspects of neutrality. On the other hand, it was not capable of solving all the issues discussed, which can be seen by the numerous diverging interpretations to apparently simple issues, such as that of the goodwill and the exemption on the distribution of dividends. In this context, this paper investigates the problem from its outset, by identifying the historic reasons for the diversity of accounting standards around the world, the Brazilian reality and the relationship between Tax law and Accounting in Brazil, to conclude on the actual influence of the new accounting standard on taxation.

Mobile cloud gaming (MCG) is an emerging concept which aims to deliver video games on-demand to users with the use of cloud technologies. Cloud technology allows the offloading of computation from a less powerful user device or thin client to more robust cloud servers to minimize power consumption and provide additional cloud services such as storage. MCG is therefore very helpful that can reduce the costs of expensive hardware, but the challenge is that it requires a high Quality of Service (QoS) in order to stream and play the games where the users have a high Quality of Experience (QoE). The goal of the study is to investigate how users' QoE is affected by network conditions while playing MCG and compare the results from a previous study. A testbed was made in order to conduct subjective tests where users are going to play Counter Strike: Global Offensive (CS: GO) on a smartphone using Steam Remote Play. The testbed consists of a router, tablet, smartphone, headset, Xbox controller, USB-C multi-port adapter and four different PC's. Participants on campus, both students and non-students, were invited to participate in the experiment. A total of 24 participants completed the tests; however, results from two participants were excluded due to software issues. There were 23 network conditions that was tested for each user and included factors such as round-trip time (RTT), packet losses, bursty jitter, random jitter or combinations of different factors. A multi-platform tool, ALTRUIST, was used to control the applications and facilitate the data collection from the devices and NetEm changed the network conditions. The results showed that the network condition [bj(rtt200i15)] had the highest mean opinion score (MOS) of the QoE of 4.5 for the users with 200 milliseconds of bursty jitter every 15 seconds. The worst network condition tested with the lowest QoE rating of 1.4 was network condition [rtt25pl12] that had 25 milliseconds of RTT and 12% packet losses. There were differences between the male and female participants where the MOS of the QoE results was significantly higher with up to 1.5 MOS QoE rating differences for the females compared to the males in network conditions with RTT with packet losses. However, the sample size was low with only 5 female participants compared to 18 male participants. The MOS of the QoE results separating play time under 10 hours per week and 10 or more hours per week showed no significant changes, where the largest QoE rating difference was 0.5 points. Network condition [rtt25pl12] and [rtt2pl35] had the largest differences in the MOS QoE ratings compared to the previous study, while both was not compared to the same corresponding network condition. The largest difference comparing the same network condition to the previous study was network condition [bj(rtt200i15)] with a difference of 1.1 points higher in the MOS QoE rating.

The rapid growth of the Internet and the proliferation of its new applications pose a serious challenge in network performance management and monitoring. The current Internet has no mechanism for providing feedback on network congestion to the end-systems at the IP layer. For applications and their end hosts, end-to-end measurements may be the only way of measuring network performance. Understanding the packet delay and loss behavior of the Internet is important for proper design of network algorithms such as routing and flow control algorithms, for the dimensioning of buffers and link capacity, and for choosing parameters in simulation and analytic studies. In this thesis, round trip time (RTT), one-way network delay and packet loss in the Internet are measured at different times of the day, using a Voice over IP (VoIP) device. The effect of clock skew on one-way network delay measurements is eliminated by a Linear Programming algorithm, implemented in MATLAB. Distributions of one-way network delay and RTT in the Internet are determined. It is observed that delay distribution has a gamma-like shape with heavy tail. It is tried to model delay distribution with gamma, lognormal and Weibull distributions. It is observed that most of the packet losses in the Internet are single packet losses. The effect of firewall on delay measurements is also observed.

Traditional methods for locating books and resources in libraries often entail browsing catalogsor manual searching that are time-consuming and inefficient. This thesis investigates thepotential of automated digital services to streamline this process, by utilizing Wi-Fi signal datafor precise indoor localization. Central to this study is the development of a model that employsWi-Fi signal strength (RSSI) and round-trip time (RTT) to estimate the locations of library userswith arm-length accuracy. This thesis aims to enhance the accuracy of location estimation byexploring the complex, nonlinear relationship between Received Signal Strength Indicator(RSSI) and Round-Trip Time (RTT) within signal fingerprints. The model was developed usingan artificial neural network (ANN) to capture the relationship between RSSI and RTT. Besides,this thesis introduces and evaluates the performance of a novel variant of the Particle SwarmOptimization (PSO) algorithm, named Randomized Particle Swarm Optimization (RPSO). Byincorporating randomness into the conventional PSO framework, the RPSO algorithm aims toaddress the limitations of the standard PSO, potentially offering more accurate and reliablelocation estimations. The PSO algorithms, including RPSO, were integrated into the trainingprocess of ANN to optimize the network’s weights and biases through direct optimization, aswell as to enhance the hyperparameters of the ANN’s built-in optimizer. The findings suggestthat optimizing the hyperparameters yields better results than direct optimization of weights andbiases. However, RPSO did not significantly enhance the performance compared to thestandard PSO in this context, indicating the need for further investigation into its application andpotential benefits in complex optimization scenarios.

I en värld där kraven på flexibilitet, säkerhet och hårdvaruoptimering är nyckelfaktorer när det kommer till att välja IT-miljöer för företag blir virtuella skrivbord mer och mer poulära. Med dessa miljöer finns det också problem när det kommer till användarupplevelsen om nätverket ifråga inte kan uppfylla de krav som ett sådant system ställer. I detta arbete undersöks implikationerna vissa nätverksvariabler kan ha för en Virtual Desktop-infrastruktur, VDI. För att belysa dessa problem har två tester utförts på en VDI miljö. Det första testet gick ut på att mäta latensen då skrivbordsmiljön renderades för klienten från virtualiseringsservern vid olika nätverksdiamterar. Det andra testet gick ut på att mäta samma latens vid olika nätverksbelasting på anslutningen mellan klienten och virtualiseringsservern. När det blev tydligt att nyckelfaktorn var nätverksbelastningen skapades ett test för att undersöka klientens möjlighet till påverkan av bandbredden. Överföringen av data till användarens lokala skrivbord som i förlängningen huseras på virtualiseringsservern tog upp hela bandbredden och lämnade inget för VDI-trafiken och stänger i förlängningen ner hela VDI systemet. Detta löstes genom att implementera Quality Of Service medelst Traffic Policing . Därmed kan användarens möjlighet att nyttja bandbredden till virtualiseringsservern begränsas. / In a world where the demand for flexibility, security, and hardware optimization are key factors when it comes to implementing a corporate IT environment Virtual Desktop solutions a gaining more and more ground. With these environments there are also issues when it comes to user experience if the network in question is unable to fulfill the specifications that such an environment requires. We have looked at the implications some network variables might have for a VDI solution. To shed a light on these issues we have conducted two tests in an VDI environment. The first test consisted of measuring the latency at which the desktop on the client was rendered from the virtualization server at different network sizes. The second test was to measure the same latency at different bandwidth loads on the line between the client and the Virtualization Host. As we realised that the key factor was the bandwidth load, we made a test to measure the way a client could influence that bandwidth. We saw that by transferring data to the desktop (i.e. the Virtualization Host) one user could personally take up the whole bandwidth and leave noting for the VDI traffic, rendering it useless. This was solved by implementing Quality of Service in the form of Traffic policing, thus restricting the amount of bandwidth the user could use for file transfers.