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In this study, a traffic generator software package namely MTGawn was developed to run packet generation and evaluation on a mobile device. The call generating software system is able to: simulate voice over Internet protocol calls as well as user datagram protocol and transmission control protocol between mobile phones over a wireless network and analyse network data similar to computer-based network monitoring tools such as Iperf and D-ITG but is self-contained on a mobile device. This entailed porting a ‘stripped down’ version of a packet generation and monitoring system with functionality as found in open source tools for a mobile platform. This mobile system is able to generate and monitor traffic over any network interface on a mobile device, and calculate the standard quality of service metrics. The tool was compared to a computer–based tool namely distributed Internet traffic generator (D-ITG) in the same environment and, in most cases, MTGawn reported comparable results to D-ITG. The important motivation for this software was to ease feasibility testing and monitoring in the field by using an affordable and rechargeable technology such as a mobile device. The system was tested in a testbed and can be used in rural areas where a mobile device is more suitable than a PC or laptop. The main challenge was to port and adapt an open source packet generator to an Android platform and to provide a suitable touchscreen interface for the tool. / >Magister Scientiae - MSc

Masters of Science / In this study, a traffic generator software package namely MTGawn was developed to run packet generation and evaluation on a mobile device. The call generating software system is able to: simulate voice over Internet protocol calls as well as user datagram protocol and transmission control protocol between mobile phones over a wireless network and analyse network data similar to computer-based network monitoring tools such as Iperf and D-ITG but is self-contained on a mobile device. This entailed porting a ‘stripped down’ version of a packet generation and monitoring system with functionality as found in open source tools for a mobile platform. This mobile system is able to generate and monitor traffic over any network interface on a mobile device, and calculate the standard quality of service metrics. The tool was compared to a computer–based tool namely distributed Internet traffic generator (D-ITG) in the same environment and, in most cases, MTGawn reported comparable results to D-ITG. The important motivation for this software was to ease feasibility testing and monitoring in the field by using an affordable and rechargeable technology such as a mobile device. The system was tested in a testbed and can be used in rural areas where a mobile device is more suitable than a PC or laptop. The main challenge was to port and adapt an open source packet generator to an Android platform and to provide a suitable touchscreen interface for the tool. ACM Categories and Subject Descriptors B.8 [PERFORMANCE AND RELIABILITY] B.8.2 [Performance Analysis and Design Aids] C.4 [PERFORMANCE OF SYSTEMS] Measurement techniques, Performance attributes

This thesis describes the design and implementation of a traffic generator that can simulate the traffic of tens of thousands of networking devices from a given traffic model. It is designed to handle traffic models created with Unified Traffic Modelling. The traffic generator is then evaluated and different solutions are compared in an effort to find the best solution for each issue. This thesis is meant to serve as a guideline for future development of traffic generators by providing insight into the problems faced during the development of one.

This work describes security mechanisms of wireless network based on 802.11 standard and security enhancement 802.11i of these networks known as WPA2, where the analysis of vulnerabilities and attacks on these networks were performed. The work discusses two major security issues. The first is unsecure management frames responsible for vulnerability with direct impact on availability and the other is the vulnerability that allows executing the impersonalize type of attacks. The system for generation attacks was designed to realize any attack very fast and efficient. The core of the thesis is the design of a system for attack analysis using the principle of trust and reputation computation. The conclusion of the work is devoted to experimenting with the proposed system, especially with the selection of suitable metrics for calculating the trust value.

As the Internet becomes an ubiquitous medium of communication, it carries more and more malicious activities like spam, worms or denial of service attacks. One solution to detect and collect such malicious traffic is to use honeypots. They are devices or pieces of information that are not part of the usual production system. Their goals are to lure the attackers into a trap to study them, divert their attention from another target or collect statistics. In this work, we propose a lightweight framework to build honeytanks, which are very efficient low-interaction honeypots. We present and evaluate techniques and algorithms to simulate the presence of a large number of hosts with various degrees of realism and scalability, from a completely stateless approach to a stateful approach able, amongst other things, to mimic the behavior of various TCP/IP stacks. Our framework is based on ASAX, a generic and lightweight data stream analyzer. We instantiate ASAX to build powerful traffic handlers. We introduce several extensions to ASAX and to RUSSEL, its programming language. These extensions allow us to develop new concurrent programming techniques to simulate hosts and protocols in a simple and modular way. We use a recently optimized version of ASAX that makes it possible to simulate tens of thousands hosts while keeping the simulation at a high level of realism. To show the benefits of our approach, i.e., greater simplicity, flexibility, and independence of other technologies, we compare our honeytanks to Honeyd and Nepenthes, two well-known low-interaction honeypots.

Made available in DSpace on 2016-04-15T22:46:21Z (GMT). No. of bitstreams: 3 Ada Castro 1.pdf: 4115645 bytes, checksum: 6db6e666980747c96cae06d7ee86368e (MD5) Ada Castro 2.pdf: 2084016 bytes, checksum: b949bebbb470e95b0ea2a84aa70ea86e (MD5) Ada Castro 3.pdf: 4460385 bytes, checksum: 534cd697b143fa0ff4e658fb6998e646 (MD5) Previous issue date: 2010-08-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / In a dynamic city as São Paulo, the relations between urban policies and mobility are often treated as distinct subjects instead of a complex structure, specially when they are related to the analysis of new property development, like residential areas. Therefore, we consider the following question as most relevant: Have society, public authorities and managers been dealing with those traffic generator poles as part of a city or as a specific situation? The approach, presently suggested for discussion, may be described as a brief review of some urban and access route expansion periods the cities have undertaken until nowadays, searching for embasement on the legislation concerning proposals involving ventures classified as Traffic Generator Poles. In addition to the legislation, it is shown a study on the pioneer methodology, applied by CET/SP since 1979 in Brazil, supported by case studies and related manuals and reports. It should be emphasized that the aim of this research is not to solve the city traffic and transportation problem, but to provide extra material for further discussions, considering the difficulties involved in obtaining information, materials and references from the responsible institutions. / Em uma cidade tão dinâmica como São Paulo, a relação entre as políticas urbanas e a mobilidade nem sempre são tratadas em conjunto e sim como assunto a parte, principalmente quando se trata da análise de um novo empreendimento imobiliário, em especial o residencial. Desta forma cabe a seguinte indagação: Como a sociedade e os órgãos públicos e gestores vêm trabalhando estes pólos geradores de tráfego, se pensando no coletivo ou como uma situação totalmente pontual? Esta é a abordagem principal proposta para discussão neste trabalho, que é feita através de uma breve recapitulação de alguns períodos de expansão urbana e viária que a cidade passou até chegar aos dias atuais, buscando um embasamento nas legislações referentes às propositivas que envolvem os empreendimentos classificados por Pólos Geradores de Tráfego. Além das legislações, é realizado um estudo sobre a metodologia pioneira no Brasil, realizada pela CET/SP desde 1979, apoiada em estudos de caso e nos manuais e relatórios da mesma. Cabe aqui ressaltar que este trabalho não tem por objetivo resolver o problema do trânsito e transporte da cidade, mas sim criar um material a mais para que futuras discussões possam vir a existir, visto a dificuldade em obter informações, materiais e referenciais por parte dos órgãos competentes

The Information and Communication Technology (ICT) industry and network researchers use traffic generator tools to a large extent to test their systems. The industry uses reliable and rigid hardware-based platform tools for high-performance network testing. The research community commonly uses software-based tools in, for example, experiments because of economic and flexibility aspects. As a result, it is possible to run these tools on different systems and hardware. In this thesis, we examine the software traffic generators Iperf, Mausezahn, Ostinato in a closed loop physical and virtual environment to evaluate the applicability of the tools and find sources of inaccuracy for a given traffic profile. For each network tool, we measure the throughput from 64- to 4096-byte in packet sizes. Also, we encapsulate each tool with container technology using Docker to reach a more reproducible and portable research. Our results show that the CPU primarily limits the throughput for small packet sizes, and saturates the 1000 Mbps link for larger packet sizes. Finally, we suggest using these tools for simpler and automated network tests. / IT-branschen och nätverksforskare använder sig av trafikgeneratorer till stor del för att testa sina system. Industrin använder sig av stabila och pålitliga hårdvaruplattformar för högpresterande nätverkstester. Forskare brukar använda mjukvarubaserade verktyg i till exempel experiment på grund av ekonomiska och flexibilitet skäl. Det är därför möjligt att använda dessa verktyg på olika system och hårdvaror. I denna avhandling undersöker vi mjukvarutrafikgeneratorerna Iperf, Mausezahn, Ostinato i en isolerad fysisk och virtuell miljö, det vill säga för att utvärdera användbarheten av verktygen och hitta felkällor för en given trafikprofil. För varje nätverksverktyg mäter vi genomströmningen från 64 till 4096 byte i paketstorlekar. Dessutom paketerar vi varje verktyg med molnteknologin Docker för att nå ett mer reproducerbart och portabelt arbete. Våra resultat visar att processorn begränsar genomströmningen för små paketstorlekar och saturerar 1000 Mbps-länken för större paketstorlekar. Slutligen föreslår vi att man kan använda dessa verktyg för enklare och automatiserade nätverkstester.

The present work aims to provide a contribution to improve the efficiency the design flow of integrated systems, focusing, specifically, on the performance evaluation of its communication structures. The use of Transaction Level Modeling (TLM) is proposed, in order to take advantage of the reduction of design effort and time. Within the performance evaluation approaches, the utilization of traffic generators instead of full system simulations started to be adopted due to its higher time efficiency. Initial works on on-chip traffic generation focused on Poisson processes and classic Markovian models, which are unable to capture Long Range Dependence (LRD). This fact led to the adoption of fractal/self-similar models. Later advancements have shown that the traffic produced in multiprocessed systems can show higher degrees of complexity, what can be attributed to the presence multifractal characteristics. In this work, a methodology to evaluate the on-chip traffic and to the development of a transaction level traffic generator is proposed. The main contributions of this work are a detailed analysis of traffic time series obtained by TLM simulations and the study of the effects of the traffic generator on these simulations, concerning, mainly, the speedup-accuracy trade-off. The proposed analysis follow the multifractal paradigm, allowing system developers to (1) understand the statistical nature of on-chip traffic, (2) to obtain accurate representations of this traffic and (3) to build traffic generators that mimic processing elements realistically. Another contribution of this work is a comparison of the performance, considering the accuracy of the obtained synthetic traffic time series, between monofractal and multifractal models. All of the mentioned contributions were grouped throughout the detailed methodology presented on the present document, for which experiments were carried out. / O presente trabalho visa oferecer uma contribuição para o aumentar a eficiência do fluxo de projeto de sistemas integrados, focando, especificamente, na avaliação do desempenho de suas estruturas de comunicação. É proposta a utilização de simulações com modelos no nível de transações (TLM), com o objetivo de se obter vantagens da redução de esforço e tempo de projeto oferecidos por esta abordagem. Dentro das propostas de análise de desempenho, a utilização de geradores de tráfego ao invés simulações de sistema completo tem sido adotada devido a sua maior eficiência no tempo. Trabalhos iniciais na geração de tráfego intrachip focaram-se em processos de Poisson e em modelos de Markov clássicos, os quais não capturam Dependência de Longa Duração (LRD). Este fato levou a adoção de modelos fractais/auto-similares. Avanços posteriores mostraram que o tráfego produzido pelos elementos de sistemas multiprocessados podem apresentar maior grau de complexidade, que pode ser atribuída à presença de características multifractais. Neste trabalho, é proposta uma metodologia para a avaliação de tráfego intrachip para o desenvolvimento de um gerador de tráfego TLM. As principais contribuições deste trabalho são uma análise detalhada das séries temporais de tráfego obtidas nas simulações TLM e o estudo dos efeitos que o gerador de tráfego exerce sobre estas simulações, se concentrando, principalmente, na relação entre precisão e aceleração da simulação. As análises propostas se baseiam no paradigma multifractal, o qual permite (1) um maior entendimento da natureza estatística do tráfego pelos desenvolvedores de sistemas, (2) a obtenção de uma representação precisa deste tráfego e (3) a construção de geradores de tráfego que substituam elementos processantes de maneira realista. Outra contribuição deste trabalho é a comparação do desempenho, no que concerne a precisão das séries de tráfego sintéticas obtidas, de modelos monofractais e multifractais. Todas as contribuições mencionadas foram agrupadas na metodologia detalhada, apresentada no presente documento, sobre a qual experimentos foram realizados.

The present work aims to provide a contribution to improve the efficiency the design flow of integrated systems, focusing, specifically, on the performance evaluation of its communication structures. The use of Transaction Level Modeling (TLM) is proposed, in order to take advantage of the reduction of design effort and time. Within the performance evaluation approaches, the utilization of traffic generators instead of full system simulations started to be adopted due to its higher time efficiency. Initial works on on-chip traffic generation focused on Poisson processes and classic Markovian models, which are unable to capture Long Range Dependence (LRD). This fact led to the adoption of fractal/self-similar models. Later advancements have shown that the traffic produced in multiprocessed systems can show higher degrees of complexity, what can be attributed to the presence multifractal characteristics. In this work, a methodology to evaluate the on-chip traffic and to the development of a transaction level traffic generator is proposed. The main contributions of this work are a detailed analysis of traffic time series obtained by TLM simulations and the study of the effects of the traffic generator on these simulations, concerning, mainly, the speedup-accuracy trade-off. The proposed analysis follow the multifractal paradigm, allowing system developers to (1) understand the statistical nature of on-chip traffic, (2) to obtain accurate representations of this traffic and (3) to build traffic generators that mimic processing elements realistically. Another contribution of this work is a comparison of the performance, considering the accuracy of the obtained synthetic traffic time series, between monofractal and multifractal models. All of the mentioned contributions were grouped throughout the detailed methodology presented on the present document, for which experiments were carried out. / O presente trabalho visa oferecer uma contribuição para o aumentar a eficiência do fluxo de projeto de sistemas integrados, focando, especificamente, na avaliação do desempenho de suas estruturas de comunicação. É proposta a utilização de simulações com modelos no nível de transações (TLM), com o objetivo de se obter vantagens da redução de esforço e tempo de projeto oferecidos por esta abordagem. Dentro das propostas de análise de desempenho, a utilização de geradores de tráfego ao invés simulações de sistema completo tem sido adotada devido a sua maior eficiência no tempo. Trabalhos iniciais na geração de tráfego intrachip focaram-se em processos de Poisson e em modelos de Markov clássicos, os quais não capturam Dependência de Longa Duração (LRD). Este fato levou a adoção de modelos fractais/auto-similares. Avanços posteriores mostraram que o tráfego produzido pelos elementos de sistemas multiprocessados podem apresentar maior grau de complexidade, que pode ser atribuída à presença de características multifractais. Neste trabalho, é proposta uma metodologia para a avaliação de tráfego intrachip para o desenvolvimento de um gerador de tráfego TLM. As principais contribuições deste trabalho são uma análise detalhada das séries temporais de tráfego obtidas nas simulações TLM e o estudo dos efeitos que o gerador de tráfego exerce sobre estas simulações, se concentrando, principalmente, na relação entre precisão e aceleração da simulação. As análises propostas se baseiam no paradigma multifractal, o qual permite (1) um maior entendimento da natureza estatística do tráfego pelos desenvolvedores de sistemas, (2) a obtenção de uma representação precisa deste tráfego e (3) a construção de geradores de tráfego que substituam elementos processantes de maneira realista. Outra contribuição deste trabalho é a comparação do desempenho, no que concerne a precisão das séries de tráfego sintéticas obtidas, de modelos monofractais e multifractais. Todas as contribuições mencionadas foram agrupadas na metodologia detalhada, apresentada no presente documento, sobre a qual experimentos foram realizados.