40 research outputs found

    Packet Filtering Based On Differentiated Services Code Point For DHCP Starvation Attacks Prevention

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    The use of the internet today has become a necessity, the most commonly used media to connect to the internet is a Wireless LAN network. For easy access to the network, DHCP service become a standard feature that must exist, because ordinary users no longer need to think about procedures for configuring IP addresses, all of which have been done automatically by the DHCP service. But it turns out that there is a security threat to DHCP service, namely DHCP Starvation attacks that can be exhausting the availability of IP addresses in DHCP service so that the configuration of IP address automatically can no longer be done on the client. Various methods such as authentication, cryptography, and machine learning are used by researchers in preventing DHCP Starvation attacks, but the issue of effectiveness and efficiency still opens up further research opportunities. In this research, packet filtering methods based on DSCP code applied to the Netfilter system are used to do prevention of DHCP Starvation attacks, this method has proven to be very effective in making prevention and more efficient when applied on small scale wireless networks such as at office networks and internet cafe.The use of the internet today has become a necessity, the most commonly used media to connect to the internet is a Wireless LAN network. For easy access to the network, DHCP service become a standard feature that must exist, because ordinary users no longer need to think about procedures for configuring IP addresses, all of which have been done automatically by the DHCP service. But it turns out that there is a security threat to DHCP service, namely DHCP Starvation attacks that can be exhausting the availability of IP addresses in DHCP service so that the configuration of IP address automatically can no longer be done on the client. Various methods such as authentication, cryptography, and machine learning are used by researchers in preventing DHCP Starvation attacks, but the issue of effectiveness and efficiency still opens up further research opportunities. In this research, packet filtering methods based on DSCP code applied to the Netfilter system are used to do prevention of DHCP Starvation attacks, this method has proven to be very effective in making prevention and more efficient when applied mainly on small and medium scale networks

    Cyber-security of Cyber-Physical Systems (CPS)

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    This master's thesis reports on security of a Cyber-Physical System (CPS) in the department of industrial engineering at UiT campus Narvik. The CPS targets connecting distinctive robots in the laboratory in the department of industrial engineering. The ultimate objective of the department is to propose such a system for the industry. The thesis focuses on the network architecture of the CPS and the availability principle of security. This report states three research questions that are aimed to be answered. The questions are: what a secure CPS architecture for the purpose of the existing system is, how far the current state of system is from the defined secure architecture, and how to reach the proposed architecture. Among the three question, the first questions has absorbed the most attention of this project. The reason is that a secure and robust architecture would provide a touchstone that makes answering the second and third questions easier. In order to answer the questions, Cisco SAFE for IoT threat defense for manufacturing approach is chosen. The architectural approach of Cisco SAFE for IoT, with similarities to the Cisco SAFE for secure campus networks, provides a secure network architecture based on business flows/use cases and defining related security capabilities. This approach supplies examples of scenarios, business flows, and security capabilities that encouraged selecting it. It should be noted that Cisco suggests its proprietary technologies for security capabilities. According to the need of the project owners and the fact that allocating funds are not favorable for them, all the suggested security capabilities are intended to be open-source, replacing the costly Cisco-proprietary suggestions. Utilizing the approach and the computer networking fundamentals resulted in the proposed secure network architecture. The proposed architecture is used as a touchstone to evaluate the existing state of the CPS in the department of industrial engineering. Following that, the required security measures are presented to approach the system to the proposed architecture. Attempting to apply the method of Cisco SAFE, the identities using the system and their specific activities are presented as the business flow. Based on the defined business flow, the required security capabilities are selected. Finally, utilizing the provided examples of Cisco SAFE documentations, a complete network architecture is generated. The architecture consists of five zones that include the main components, security capabilities, and networking devices (such as switches and access points). Investigating the current state of the CPS and evaluating it by the proposed architecture and the computer networking fundamentals, helped identifying six important shortcomings. Developing on the noted shortcomings, and identification of open-source alternatives for the Cisco-proprietary technologies, nine security measures are proposed. The goal is to perform all the security measures. Thus, the implementations and solutions for each security measure is noted at the end of the presented results. The security measures that require purchasing a device were not considered in this project. The reasons for this decision are the time-consuming process of selecting an option among different alternatives, and the prior need for grasping the features of the network with the proposed security capabilities; features such as amount and type of traffic inside the network, and possible incidents detected using an Intrusion Detection Prevention System. The attempts to construct a secure cyber-physical system is an everlasting procedure. New threats, best practices, guidelines, and standards are introduced on a daily basis. Moreover, business needs could vary from time to time. Therefore, the selected security life-cycle is required and encouraged to be used in order to supply a robust lasting cyber-physical system

    MITM Attack Automation Using Single-Board Solution

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    Práca je zameraná na návrh MiTM útokov s využitím moderných prístupov pri návrhu IT infraštruktúri. Špecificky sa zameriava na možnosti využitia jednodoskových počítačov a na možnosti ako zjednodušiť ich kofiguráciu pre účely penetračného testovania. Navrhnuté a implementované riešenie umožnuje použitie komplikovaných útokov personálom, ktorý je len zaškolený, pričom neobmedzuje použitie skúseným personálom. Zatiaľ čo dnešné prístupy by sa dali považovať sa monolitické a centrické, navrhnuté riešenie berie samotný MiTM útok len ako časť riešenia pričom sa zameriava aj na ostatné aspekty ako napríklad exfiltrácia dát, alebo crackovanie hesiel.Thesis is focused on design of MiTM attack with use of modern approaches in IT infrastructure. Especially it's focused on how to simplify configuration of single-board computer for penetration testing purposes by creating scalable infrastructure for device configuration and control. Proposed solution allows the usage of complicated attacks by trained staff while not limiting users with experience in network security. While today, applications capable of MiTM attacks are monolithic and device-centric, proposed solution considers the device providing MiTM just as one part of the solution and also focuses on other problems like data exfiltration or hash cracking.

    {SoK}: {An} Analysis of Protocol Design: Avoiding Traps for Implementation and Deployment

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    Today's Internet utilizes a multitude of different protocols. While some of these protocols were first implemented and used and later documented, other were first specified and then implemented. Regardless of how protocols came to be, their definitions can contain traps that lead to insecure implementations or deployments. A classical example is insufficiently strict authentication requirements in a protocol specification. The resulting Misconfigurations, i.e., not enabling strong authentication, are common root causes for Internet security incidents. Indeed, Internet protocols have been commonly designed without security in mind which leads to a multitude of misconfiguration traps. While this is slowly changing, to strict security considerations can have a similarly bad effect. Due to complex implementations and insufficient documentation, security features may remain unused, leaving deployments vulnerable. In this paper we provide a systematization of the security traps found in common Internet protocols. By separating protocols in four classes we identify major factors that lead to common security traps. These insights together with observations about end-user centric usability and security by default are then used to derive recommendations for improving existing and designing new protocols---without such security sensitive traps for operators, implementors and users

    {SoK}: {An} Analysis of Protocol Design: Avoiding Traps for Implementation and Deployment

    No full text
    Today's Internet utilizes a multitude of different protocols. While some of these protocols were first implemented and used and later documented, other were first specified and then implemented. Regardless of how protocols came to be, their definitions can contain traps that lead to insecure implementations or deployments. A classical example is insufficiently strict authentication requirements in a protocol specification. The resulting Misconfigurations, i.e., not enabling strong authentication, are common root causes for Internet security incidents. Indeed, Internet protocols have been commonly designed without security in mind which leads to a multitude of misconfiguration traps. While this is slowly changing, to strict security considerations can have a similarly bad effect. Due to complex implementations and insufficient documentation, security features may remain unused, leaving deployments vulnerable. In this paper we provide a systematization of the security traps found in common Internet protocols. By separating protocols in four classes we identify major factors that lead to common security traps. These insights together with observations about end-user centric usability and security by default are then used to derive recommendations for improving existing and designing new protocols---without such security sensitive traps for operators, implementors and users

    IPv6: a new security challenge

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    Tese de mestrado em Segurança Informática, apresentada à Universidade de Lisboa, através da Faculdade de Ciências, 2011O Protocolo de Internet versão 6 (IPv6) foi desenvolvido com o intuito de resolver alguns dos problemas não endereçados pelo seu antecessor, o Protocolo de Internet versão 4 (IPv4), nomeadamente questões relacionadas com segurança e com o espaço de endereçamento disponível. São muitos os que na última década têm desenvolvido estudos sobre os investimentos necessários à sua adoção e sobre qual o momento certo para que o mesmo seja adotado por todos os players no mercado. Recentemente, o problema da extinção de endereçamentos públicos a ser disponibilizado pelas diversas Region Internet registry – RIRs - despertou o conjunto de entidades envolvidas para que se agilizasse o processo de migração do IPv4 para o IPv6. Ao contrário do IPv4, esta nova versão considera a segurança como um objetivo fundamental na sua implementação, nesse sentido é recomendado o uso do protocolo IPsec ao nível da camada de rede. No entanto, e devido à imaturidade do protocolo e à complexidade que este período de transição comporta, existem inúmeras implicações de segurança que devem ser consideradas neste período de migração. O objetivo principal deste trabalho é definir um conjunto de boas práticas no âmbito da segurança na implementação do IPv6 que possa ser utilizado pelos administradores de redes de dados e pelas equipas de segurança dos diversos players no mercado. Nesta fase de transição, é de todo útil e conveniente contribuir de forma eficiente na interpretação dos pontos fortes deste novo protocolo assim como nas vulnerabilidades a ele associadas.IPv6 was developed to address the exhaustion of IPv4 addresses, but has not yet seen global deployment. Recent trends are now finally changing this picture and IPv6 is expected to take off soon. Contrary to the original, this new version of the Internet Protocol has security as a design goal, for example with its mandatory support for network layer security. However, due to the immaturity of the protocol and the complexity of the transition period, there are several security implications that have to be considered when deploying IPv6. In this project, our goal is to define a set of best practices for IPv6 Security that could be used by IT staff and network administrators within an Internet Service Provider. To this end, an assessment of some of the available security techniques for IPv6 will be made by means of a set of laboratory experiments using real equipment from an Internet Service Provider in Portugal. As the transition for IPv6 seems inevitable this work can help ISPs in understanding the threats that exist in IPv6 networks and some of the prophylactic measures available, by offering recommendations to protect internal as well as customers’ networks

    Actas da 10ª Conferência sobre Redes de Computadores

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    Universidade do MinhoCCTCCentro AlgoritmiCisco SystemsIEEE Portugal Sectio

    Mitigating TCP Degradation over Intermittent Link Failures Using Intermediate Buffers

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    This thesis addresses the improvement of data transmission performance in a challenged network. It is well known that the popular Transmission Control Protocol degrades in environments where one or more of the links along the route is intermittently available. To avoid this degradation, this thesis proposes placing at least one node along the path of transmission to buffer and retransmit as needed to overcome the intermittent link. In the four-node, three-link testbed under particular conditions, file transmission time was reduced 20 fold in the case of an intermittent second link when the second node strategically buffers for retransmission opportunity
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