Optimization methods for the performance enhancement of thin client computing over bandwidth-limited and slow links

Ph.DDOCTOR OF PHILOSOPH

Performance Analysis of VPN Remote Access Tunnels

The purpose of the study is to analyze the efficiency of communication with the serverusing the methods of secure remote access, as well as checking and comparing the quality of servicesprovided by the server depending on the method of secure remote connection. The article focuses onVPN technology implemented in the latest Windows Server 2012 R2 operating system

Tunneling and Cryptographic protocols as a privacy protection on regulated internet

Tato práce pojednává o regulacích internetu a využití tunelovacích protokolů pro ochranu soukromí na regulovaném internetu. V práci je uveden přehled a podrobný popis nejrozšířenějších tunelovacích protokolů se zaměřením na jejich použití v regulovaných sítích. Výstupem teoretické části práce je přehledná tabulka, kde jsou uvedeny výhody a nevýhody jednotlivých protokolů a dále situace, pro které je vhodné daný protokol použít. V praktické části práce jsou prezentovány jednotlivé tunelovací protokoly na třech v praxi se často vyskytujících scénářích. Každé řešení bylo praktický realizováno, bylo provedeno zachycení datového provozu pomocí programu Wireshark a byla provedena analýza možných rizik pro případ, že by došlo k odposlechnutí komunikace třetí stranou - regulátorem.This thesis is about internet regulations and usage of tunneling protocols as a privacy protection on regulated internet. The thesis includes detailed description of most widely used tunneling protocols focused on their usage in regulated networks. The produce the teoretical part of the thesis is synoptical comparative table including benefits and disadvantages of each protocol and examples of suitable usage. The practical part presents the tunneling protocols in three different scenarios which are very frequent in practice. Each scenario has been realized, the communication has been captured using Wireshark network protocol analyzer and also the analysis of potential risks has been done for the event that the communication would be captured by a third party - the regulator.

Redes domésticas seguras

Tese de mestrado integrado. Engenharia Electrotécnica e de Computadores. Faculdade de Engenharia. Universidade do Porto. 200

A novel approach for the hardware implementation of a PPMC statistical data compressor

This thesis aims to understand how to design high-performance compression algorithms suitable for hardware implementation and to provide hardware support for an efficient compression algorithm. Lossless data compression techniques have been developed to exploit the available bandwidth of applications in data communications and computer systems by reducing the amount of data they transmit or store. As the amount of data to handle is ever increasing, traditional methods for compressing data become· insufficient. To overcome this problem, more powerful methods have been developed. Among those are the so-called statistical data compression methods that compress data based on their statistics. However, their high complexity and space requirements have prevented their hardware implementation and the full exploitation of their potential benefits. This thesis looks into the feasibility of the hardware implementation of one of these statistical data compression methods by exploring the potential for reorganising and restructuring the method for hardware implementation and investigating ways of achieving efficient and effective designs to achieve an efficient and cost-effective algorithm. [Continues.

Homebrew and the social construction of gaming : community, creativity, and legal context of amateur Game Boy Advance development

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Comparative Media Studies, 2005.Includes bibliographical references (leaves 147-156).This thesis challenges the common social construction of game development, which perceives the activity only within its commercial, corporate realm. As an exemplar of the many thriving amateur development communities, the self-identified "homebrew" Nintendo Game Boy Advance (GBA) development community is analyzed in-depth. This unique community is brought to the attention of scholars as an important intersection of game studies and amateur media studies, challenging the focus of game studies on commercial production. The GBA homebrew community is studied from the personal motivational level to the social dynamics of the group. The analysis considers the blend of technological and cultural motivations brought to bear on the production and the content of the amateur games, and how amateur development facilitates skill acquisition outside of canonical academic structure, and opens access to professional mobility. The case study advances both historical and contemporary comparisons to other independent media communities. The thesis also examines discussions in the community around peer-judged competitions as a form of vernacular theory. The content of homebrew GBA games released into the community are further analyzed, with the construction of useful categories spanning genre, fan games, remakes, remixes, and tech demos. Nostalgia and parody in relation to game history are especially considered, as are demonstrations of technical skill ("tech demos") as a uniquely amateur practice. The legal context of amateur GBA development is also examined. Nintendo maintains the GBA as a closed, proprietary system, and thus for homebrew developers access to information and legitimacy is blocked.(cont.) Comparisons are advanced to historical examples of intellectual property enforcement in the emergence of corporate media in the 20th century. Amateur practice is found to be tangential to corporate interests, ignored both by the disinterest of corporations, and in blanket policies targeting piracy. Historical cases that legitimate reverse engineering of software are discussed for context. Thesis concludes that one cannot cleanly construct categories of amateur and professional as separate practices, and remarks upon the constant renewal and shifts in amateur development communities as new game platforms are released in the commercial market.by Brett Bennett Camper.S.M

Progress Towards Controlled Re-entry and Recovery of CubeSats

The primary objective of this work was to progress towards performing controlled re-entry and recovery missions using CubeSats to increase the frequency of Solar System exploration missions such as extra-terrestrial sample collection and return and planetary Entry, Descent, and Landing. By developing a novel CubeSat platform and further methods to track CubeSats, the cost of developing technologies for these missions has been reduced, meeting the primary objective and enabling more planetary science research opportunities

New Horizons in Time-Domain Diffuse Optical Spectroscopy and Imaging

Jöbsis was the first to describe the in vivo application of near-infrared spectroscopy (NIRS), also called diffuse optical spectroscopy (DOS). NIRS was originally designed for the clinical monitoring of tissue oxygenation, and today it has also become a useful tool for neuroimaging studies (functional near-infrared spectroscopy, fNIRS). However, difficulties in the selective and quantitative measurements of tissue hemoglobin (Hb), which have been central in the NIRS field for over 40 years, remain to be solved. To overcome these problems, time-domain (TD) and frequency-domain (FD) measurements have been tried. Presently, a wide range of NIRS instruments are available, including commonly available commercial instruments for continuous wave (CW) measurements, based on the modified Beer–Lambert law (steady-state domain measurements). Among these measurements, the TD measurement is the most promising approach, although compared with CW and FD measurements, TD measurements are less common, due to the need for large and expensive instruments with poor temporal resolution and limited dynamic range. However, thanks to technological developments, TD measurements are increasingly being used in research, and also in various clinical settings. This Special Issue highlights issues at the cutting edge of TD DOS and diffuse optical tomography (DOT). It covers all aspects related to TD measurements, including advances in hardware, methodology, the theory of light propagation, and clinical applications

Technology from the Perspective of Society and Public Interest

The ultimate goals of this study were to determine ways to reconcile technology with public interest and to understand the relationship between what we know and how we feel about technology. To achieve the goals, related literatures were reviewed; the mechanism of technology development was described with empirical data; and human perception of technology was tested with a survey. The duality of technology that implied technological inherencies of technical reason and social meanings was the principle assumption of the study. Neutrality of technology becomes a myth with the presence of social meanings embodied in technology. Given the huge impact of technology on human societies, the absence of neutrality is, in turn, attributed to the necessity for policy. Analyses of eight empirical cases of technology in history based on the method of grounded theory provided core categories of technical progress, economic values, and social inclinations. Upon the core categories and concepts corroborated by the cases, the mechanism of technology development appeared to be a concatenation of the interactions between technical progress and social demand of either economic values or social inclinations. Technology that is pertinent to public interest, in this context, will be possible if a social inclination toward public interest can be built. The state can shape a social inclination of the kind and intervene in the mechanism of technology development. Furthermore, such an intervention could be accelerated by the potency of the collective actions of citizens. If successful, technology will incorporate the social value of public interest and the paradigm of technology will embrace it. Survey responses indicated that the biggest misconception of technology was in the concept of technological knowledge, which especially was supposed to be distinguished from scientific knowledge; technology was perceived to have a distinctive kind of knowledge and to be practical, but still to be a part of science pursuing the knowledge of nature. Technology still seemed to be a mere part of science with more emphasis on practical purpose in everyday life, which was concurred with the term applied science. The respondents agreed on the idea of value-ladeness of technology and, thus, necessity for human control over technology. However, they appeared to have relatively passive attitudes toward technology. The conflict between the necessity for control and the paucity of faith in the ability to control technology by themselves must attribute respondents’ dependency toward experts. The correlation between understanding of technology and will to control technology was statistically significant but weak. The control variables of academic affiliation and department were found to have significant effects on the results

Automotive embedded systems software reprogramming

This thesis was submitted for the degree of Doctor of Philosophy and was awarded by Brunel UniversityThe exponential growth of computer power is no longer limited to stand alone computing systems but applies to all areas of commercial embedded computing systems. The ongoing rapid growth in intelligent embedded systems is visible in the commercial automotive area, where a modern car today implements up to 80 different electronic control units (ECUs) and their total memory size has been increased to several hundreds of megabyte. This growth in the commercial mass production world has led to new challenges, even within the automotive industry but also in other business areas where cost pressure is high. The need to drive cost down means that every cent spent on recurring engineering costs needs to be justified. A conflict between functional requirements (functionality, system reliability, production and manufacturing aspects etc.), testing and maintainability aspects is given. Software reprogramming, as a key issue within the automotive industry, solve that given conflict partly in the past. Software Reprogramming for in-field service and maintenance in the after sales markets provides a strong method to fix previously not identified software errors. But the increasing software sizes and therefore the increasing software reprogramming times will reduce the benefits. Especially if ECU’s software size growth faster than vehicle’s onboard infrastructure can be adjusted. The thesis result enables cost prediction of embedded systems’ software reprogramming by generating an effective and reliable model for reprogramming time for different existing and new technologies. This model and additional research results contribute to a timeline for short term, mid term and long term solutions which will solve the currently given problems as well as future challenges, especially for the automotive industry but also for all other business areas where cost pressure is high and software reprogramming is a key issue during products life cycle