This diploma thesis deals with familiarization with available frameworks in the PHP language working in a thin client environment. It focuses on the comparison of two frameworks CodeIgniter and Zend Framework. The next section provides a detailed description of framework libraries. I suggested sample application made by two frameworks for a comparison, which contains the basic elements, that are used in creating majority of web applications. In the conclusion there are compared pros and cons of development environments.

Développer un système de rendu distant pour terminaux légers et mobiles traitant d'objets multimédias et de leur sémantique consiste à (1) offrir une véritable expérience multimédia collaborative au niveau du terminal, (2) assurer la compatibilité avec les contraintes liées au réseau (bande passante, erreurs et latence variables en temps) et au terminal (ressources de calcul et de mémoire réduites) et (3) s'affranchir des types de terminaux et des spécificités des communautés.Cette thèse traite de ces enjeux et se positionne en rupture avec l'état de l'art en développant une architecture support fondée sur la gestion sémantique du contenu multimédia. Le principe consiste à convertir en temps réel le contenu graphique généré par l'application en un graphe de scène multimédia et à le gérer en fonction de la sémantique de ses composantes.L'optimisation de la bande passante est assurée par la compression adaptative du graphe de scène et par la compression sans perte des messages de collaboration. Les deux méthodes développées sont caractérisées respectivement par la création d'un unique graphe de scène intrinsèquement adaptable au réseau/terminal et par la mise à jour dynamique du dictionnaire de codage en fonction des messages générés par les utilisateurs. Elles sont brevetées.Les fonctionnalités collaboratives interviennent directement au niveau du contenu grâce à l'enrichissement du graphe de scène par un nouveau type de nœud, dont la normalisation ISO est en cours.Le démonstrateur logiciel sous-jacent, dénommé MASC (Multimedia Adaptive Semantic Collaboration), permet de comparer objectivement cette nouvelle architecture aux solutions actuellement déployées par des acteurs majeurs du domaine (VNC RBF ou Microsoft RDP). Deux types d'application ont été considérés : l'édition du texte et la navigation sur Internet. Les évaluations quantitatives montrent: (1) un impact limité des artéfacts visuels de conversion (PSNR compris entre 30 et 42 dB et SSIM supérieur à 0,9999), (2) consommation de la bande passante downlink (resp. uplink) réduite d'un facteur de 2 à 60 (resp. de 3 à 10), (3) latence dans la transmission des événements générés par l'utilisateur réduite d'un facteur de 4 à 6, (4) consommation des ressources de calcul côté client réduite d'un facteur 1,5 par rapport à VNC RFB. / Defining a multimedia remote viewer for mobile thin clients comes across with threefold scientific/technical constraints: (1) providing at the client side heterogeneous multimedia content and the support for ultimate collaboration functionalities, (2) ensuring a stable quality of services despite constrained resources available for the network and the terminal, and (3) featuring terminal independency and benefiting from community support.The present thesis addresses these challenges by developing a collaborative, semantic multimedia remote viewer. The underlying architecture features novel components for scene-graph creation and management, as well as for collaborative user events handling.The adaptive compression of the multimedia scene graph and the lossless compression of the collaborative messages are optimized through two devoted algorithms. The former creates a unique scene-graph, intrinsically adaptable to the network/terminal conditions. The latter dynamically generates and updates the encoding table according to the messages generated by the collaborative users. Both algorithms are patented.The direct collaborative functionality is ensured at the content level by enriching the scene graph with a new type of node where currently becomes a part of the ISO standards.The experimental setup considers the Linux X windows system and BiFS/LASeR multimedia scene technologies on the server and client sides, respectively. The implemented solution was objectively benchmarked against currently deployed solutions (VNC RFB and Microsoft RDP), by considering text-editing and www-browsing applications. The quantitative assessments demonstrate: (1) limited depreciation of the visual quality, e.g. PSNR values between 30 and 42dB or SSIM values larger than 0.9999; (2) downlink bandwidth gain factors ranging from 2 to 60; (3) efficient real-time user event management expressed by network roundtrip-time reduction by factors of 4 to 6 and by up-link bandwidth gain factors from 3 to 10; (4) feasible CPU activity, larger than in the Microsoft RDP case but reduced by a factor of 1.5 with respect to the VNC RFB.

Då datorer i alla dess former har kommit att bära betydande mängder relevant information för diverse forensiska utredningar så krävs en ingående kunskap gällande hur denna data lämpligast infångas. En typ av klient som nyligen har gjort sitt kommersiella intåg på marknaden är den internetbaserade tunna klienten. Det existerar i dagsläget begränsat med underlag gällande huruvida en sådan klient bär information som är relevant för en IT-forensisk utredning. Inom denna uppsats har därför en internetbaserad tunn klient av typen Chromebook varit mål för undersökning. Syftet har varit att kartlägga vilka sårbarheter som existerar, samt om möjligt huruvida dessa kan brukas som underlag vid en forensisk utredning. För detta ändamål har klientens lagrings- samt kommunikationsmönster analyserats. För genomförandet av detta brukades experimentella metodiker i form av penetrationstest samt IT-forensisk undersökning. Det har även kartlagts huruvida programvaror avsedda för operativsystemet Linux kan exekveras på klienten. Ändamålet med detta var att fastställa om klientens volatila minne kan utvinnas med hjälp av verktyg för just Linux. Rapportens resultat påvisar att det inom en klient av denna typ finns forensiskt värdefull information att inhämta. Det påvisas även att Chrome OS från en användares perspektiv kan anses som säkert. / Computers in various forms have come to carry a significant amount of relevant information for various forensic investigations. Therefore, detailed knowledge is required regarding how this data is best acquired. One type of client that has recently made its entry onto the commercial market is the Web Thin Client. As it is today, only a limited amount of relevant information can be found regarding in what capacity such a client contains data that is relevant to an IT-forensic investigation. For this reason, a Web thin client of the model Google Chromebook has been evaluated in this paper. The purpose of this examination has been to identify the vulnerabilities that currently exist, and if possible whether these can be used as a basis for a forensic investigation. To achieve this, the client's storage and communication patterns have been analyzed by implementation of experimental methodologies. The methods used for the purpose are penetration testing and an IT forensic investigation. Tests have also been performed to evaluate whether software for the Linux operating system can be executed on the client. The purpose of this was to determine whether the client's volatile memory can be extracted using tools created for Linux. The results presented in this paper demonstrate the fact that within a client of this type, valuable forensic information can be located. It is also established that Chrome OS from a user's perspective can be considered as safe.

The thesis contains a proposal and implementation of an environment convenient for operation of network client applications which use common terminals. It also consists of implemented examples where the way of their usage is presented. The centralized way of communication is the basis. The approach is used also for the possibility of their joining with managing subsystems, i.e. unlimited ways of regulation of systems for real estate management, access to devices, user authority access to access data points to the devices. The environment is based on operation system Linux and database MySQL. Their realization is supposed on a server, in the network environment. This relates also to the overall security policy and this work also focused on social treatment of clients possibilities.

This thesis focuses on designing and developing a centralized management and configuration solution for the thin clients offered by the OldanyGroup s.r.o. company. The purpose of this application is to simplify the thin client administration and control for customers as well as to improve the competitiveness of the whole thin client solution offered by the company.

Virtualisation is a technology that is more and more applied due to its advantages regarding cost and operation. It is often believed that it provides a better security for an IT environment since it enables centralisation of hardware. However, virtualisation changes an IT environment fundamentally and contains new vulnerabilities that must be considered. It is of interest to evaluate whether the belief that virtual environments provide a better security for an IT environment is true or not. In this project, the resiliency against attacks for physical environments and virtual environments is analysed to determine which one provides a higher resiliency and why. Therefore, the physical and digital attack surfaces of all entities are analysed to reveal the relevant vulnerabilities that could be exploited. Beside a theoretical research, a physical and a virtual environment have been established to test chosen attacks practically. The results show that virtual environments are less resilient than physical environments, especially to common attacks. This shows that virtualisation is still a technology that is new to many companies and the vulnerabilities it has must be taken seriously.

Made available in DSpace on 2016-04-04T18:31:36Z (GMT). No. of bitstreams: 1 Vitor Chaves de Oliveira.pdf: 1928054 bytes, checksum: 49bf6198a68438069d6ef8b9a2ec77e9 (MD5) Previous issue date: 2012-12-10 / In recent years, virtualization computing has become a worldwide reality present in datacenters servers of most organizations. The motivations for the use of this solution are focused primarily on cost reduction and increases in availability, integrity and security of data. Based on these benefits, recently it was started the use of this technology for personal computers as well. That is, for desktops, giving birth to the so-called desktop virtualization. Given the technical advantages of the approach, its growth has been so significant that, before 2014, it is expected to be present in over 90% of organizations. However, this new method is completely based on a physical client-server architecture, which increases the importance of the communication network that makes this technique possible. Therefore, analyzing the network in order to investigate the effects according to the environment implemented, becomes crucial. In this work it s varied the local s client hardware and the application, i.e. the service used. The purpose was to detail their effects on computer networks in a Quality of Service (QoS) parameter, throughput. Secondarily are outlined perceptions regarding the Quality of Experience (QoE). / Nos ?ltimos anos, a virtualiza??o computacional se tornou uma realidade nos servidores presentes nos data-centers da maioria das organiza??es no mundo. As motiva??es para o emprego desta solu??o est?o centradas, primordialmente, na redu??o de custos e em aumentos na disponibilidade, na integridade e na seguran?a dos dados. Com base nestes benef?cios, recentemente, se come?ou a aproveitar esta tecnologia tamb?m para os computadores pessoais. Isto ?, para os desktops, dando origem a chamada virtualiza??o de desktop. Dadas as vantagen t?cnicas da abordagem, seu crescimento tem sido t?o expressivo que, antes de 2014, se espera que ela esteja presente em mais de 90% das organiza??es. Todavia, este m?todo ? totalmente baseado em uma arquitetura cliente-servidor f?sica, o que aumenta a import?ncia da rede de comunica??o que torna a t?cnica poss?vel. Logo, analisar a rede, a fim de investigar os impactos de acordo com o ambiente implementado, se torna fundamental. Neste trabalho variamos o hardware local do cliente e a aplica??o, isto ?, o servi?o utilizado. A finalidade foi a de detalhar seus efeitos, em redes de computadores, em um par?metro de Qualidade de Servi?o (QoS), a vaz?o. Secundariamente s?o esbo?adas percep??es de Qualidade da Experi?ncia (QoE).

<p>Stress responsive genes play a key role in shaping the manner in which plants process and respond to environmental stress. Their gene products are linked to DNA transcription and its consequent translation into a response product. However, whilst these genes play a significant role in manufacturing responses to stressful stimuli, transcription factors coordinate access to these genes, specifically by accessing a gene&rsquo / s promoter region which houses transcription factor binding sites. Here transcriptional elements play a key role in mediating responses to environmental stress where each transcription factor binding site may constitute a potential response to a stress signal. Arabidopsis thaliana, a model organism, can be used to identify the mechanism of how transcription factors shape a plant&rsquo / s survival in a stressful environment. Whilst there are numerous plant stress research groups, globally there is a shortage of publicly available stress responsive gene databases. In addition a number of previous databases such as the Generation Challenge Programme&rsquo / s comparative plant stressresponsive gene catalogue, Stresslink and DRASTIC have become defunct whilst others have stagnated. There is currently a single Arabidopsis thaliana stress response database called STIFDB which was launched in 2008 and only covers abiotic stresses as handled by major abiotic stress responsive transcription factor families. Its data was sourced from microarray expression databases, contains numerous omissions as well as numerous erroneous entries and has not been updated since its inception.The Dragon Arabidopsis Stress Transcription Factor database (DASTF) was developed in response to the current lack of stress response gene resources. A total of 2333 entries were downloaded from SWISSPROT, manually curated and imported into DASTF. The entries represent 424 transcription factor families. Each entry has a corresponding SWISSPROT, ENTREZ GENBANK and TAIR accession number. The 5&rsquo / untranslated regions (UTR) of 417 families were scanned against TRANSFAC&rsquo / s binding site catalogue to identify binding sites. The relational database consists of two tables, namely a transcription factor table and a transcription factor family table called DASTF_TF and TF_Family respectively. Using a two-tier client-server architecture, a webserver was built with PHP, APACHE and MYSQL and the data was loaded into these tables with a PYTHON script. The DASTF database contains 60 entries which correspond to biotic stress and 167 correspond to abiotic stress while 2106 respond to biotic and/or abiotic stress. Users can search the database using text, family, chromosome and stress type search options. Online tools have been integrated into the DASTF&nbsp / database, such as HMMER, CLUSTALW, BLAST and HYDROCALCULATOR. User&rsquo / s can upload sequences to identify which transcription factor family their sequences belong to by using HMMER. The website can be accessed at http://apps.sanbi.ac.za/dastf/ and two updates per year are envisaged.</p>

<p>Stress responsive genes play a key role in shaping the manner in which plants process and respond to environmental stress. Their gene products are linked to DNA transcription and its consequent translation into a response product. However, whilst these genes play a significant role in manufacturing responses to stressful stimuli, transcription factors coordinate access to these genes, specifically by accessing a gene&rsquo / s promoter region which houses transcription factor binding sites. Here transcriptional elements play a key role in mediating responses to environmental stress where each transcription factor binding site may constitute a potential response to a stress signal. Arabidopsis thaliana, a model organism, can be used to identify the mechanism of how transcription factors shape a plant&rsquo / s survival in a stressful environment. Whilst there are numerous plant stress research groups, globally there is a shortage of publicly available stress responsive gene databases. In addition a number of previous databases such as the Generation Challenge Programme&rsquo / s comparative plant stressresponsive gene catalogue, Stresslink and DRASTIC have become defunct whilst others have stagnated. There is currently a single Arabidopsis thaliana stress response database called STIFDB which was launched in 2008 and only covers abiotic stresses as handled by major abiotic stress responsive transcription factor families. Its data was sourced from microarray expression databases, contains numerous omissions as well as numerous erroneous entries and has not been updated since its inception.The Dragon Arabidopsis Stress Transcription Factor database (DASTF) was developed in response to the current lack of stress response gene resources. A total of 2333 entries were downloaded from SWISSPROT, manually curated and imported into DASTF. The entries represent 424 transcription factor families. Each entry has a corresponding SWISSPROT, ENTREZ GENBANK and TAIR accession number. The 5&rsquo / untranslated regions (UTR) of 417 families were scanned against TRANSFAC&rsquo / s binding site catalogue to identify binding sites. The relational database consists of two tables, namely a transcription factor table and a transcription factor family table called DASTF_TF and TF_Family respectively. Using a two-tier client-server architecture, a webserver was built with PHP, APACHE and MYSQL and the data was loaded into these tables with a PYTHON script. The DASTF database contains 60 entries which correspond to biotic stress and 167 correspond to abiotic stress while 2106 respond to biotic and/or abiotic stress. Users can search the database using text, family, chromosome and stress type search options. Online tools have been integrated into the DASTF&nbsp / database, such as HMMER, CLUSTALW, BLAST and HYDROCALCULATOR. User&rsquo / s can upload sequences to identify which transcription factor family their sequences belong to by using HMMER. The website can be accessed at http://apps.sanbi.ac.za/dastf/ and two updates per year are envisaged.</p>

The presented work concerns problems of more effective using hardware and also free software. The first part of my work presents generally free GNU/Linux distributions and this part is concentrated on two distributions. The first is Red Hat Enterprise Linux which is installed in the server of the hospital information system Clinicom. The second is live distribution Slax that is used for testing of terminal connection to the hospital information system Clinicom. The second part of my work is generally concentrated on the hospital information systems and there is presented the firm SMS solution at the end. It is the hospital information system Clinicom. The next part is generally concentrated on the workload server monitoring. It monitors both userlogins and allocated memory size. Then there are discused problems of solution of unthought-of events, for example blackout, and the one solution is described there. The last part is concentrated on implementation of the security connection to the hospital information system Clinicom and it presents live distribution Slax as distribution for thin client.