Robust peer-to-peer systems

textPeer-to-peer (p2p) approaches are an increasingly effective way to deploy services. Popular examples include BitTorrent, Skype, and KaZaA. These approaches are attractive because they can be highly fault-tolerant, scalable, adaptive, and less expensive than a more centralized solution. Cooperation lies at the heart of these strengths. Yet, in settings where working together is crucial, a natural question is: "What if users stop cooperating?" After all, cooperative services are typically deployed over multiple administrative domains, and thus vulnerable to Byzantine failures and users who may act selfishly. This dissertation explores how to construct p2p systems to tolerate Byzantine participants while also incentivizing selfish participants to contribute resources. We describe how to balance obedience against choice in building a robust p2p live streaming system. Imposing obedience is desirable as it leaves little room for peers to attack or cheat the system. However, providing choice is also attractive as it allows us to engineer flexible and efficient solutions. We first focus on obedience by using Nash equilibria to drive the design of BAR Gossip, the first gossip protocol that is resilient to Byzantine and selfish nodes. BAR Gossip relies on verifiable pseudo-random partner selection to eliminate non-determinism, which can be used to game the system, while maintaining the robustness and rapid convergence of traditional gossip. A novel fair enough exchange primitive entices cooperation among selfish peers on short timescales, thereby avoiding the need for distributed reputation schemes. We next focus on tempering obedience with choice by using approximate equilibria to guide the construction of a novel p2p live streaming system. These equilibria allow us to design incentives to limit selfish behavior rigorously, yet provide sufficient flexibility to build practical systems. We show the advantages of using an [element of]-Nash equilibrium, instead of an exact Nash, to design and implement FlightPath, our live streaming system that uses bandwidth efficiently, absorbs flash crowds, adapts to sudden peer departures, handles churn, and tolerates malicious activity.Computer Science

Ubiquitous robust communications for emergency response using multi-operator heterogeneous networks

A number of disasters in various places of the planet have caused an extensive loss of lives, severe damages to properties and the environment, as well as a tremendous shock to the survivors. For relief and mitigation operations, emergency responders are immediately dispatched to the disaster areas. Ubiquitous and robust communications during the emergency response operations are of paramount importance. Nevertheless, various reports have highlighted that after many devastating events, the current technologies used, failed to support the mission critical communications, resulting in further loss of lives. Inefficiencies of the current communications used for emergency response include lack of technology inter-operability between different jurisdictions, and high vulnerability due to their centralized infrastructure. In this article, we propose a flexible network architecture that provides a common networking platform for heterogeneous multi-operator networks, for interoperation in case of emergencies. A wireless mesh network is the main part of the proposed architecture and this provides a back-up network in case of emergencies. We first describe the shortcomings and limitations of the current technologies, and then we address issues related to the applications and functionalities a future emergency response network should support. Furthermore, we describe the necessary requirements for a flexible, secure, robust, and QoS-aware emergency response multi-operator architecture, and then we suggest several schemes that can be adopted by our proposed architecture to meet those requirements. In addition, we suggest several methods for the re-tasking of communication means owned by independent individuals to provide support during emergencies. In order to investigate the feasibility of multimedia transmission over a wireless mesh network, we measured the performance of a video streaming application in a real wireless metropolitan multi-radio mesh network, showing that the mesh network can meet the requirements for high quality video transmissions

Intrusion detection system in software-defined networks

Mestrado de dupla diplomação com a UTFPR - Universidade Tecnológica Federal do ParanáSoftware-Defined Networking technologies represent a recent cutting-edge paradigm in network management, offering unprecedented flexibility and scalability. As the adoption of SDN continues to grow, so does the urgency of studying methods to enhance its security. It is the critical importance of understanding and fortifying SDN security, given its pivotal role in the modern digital ecosystem. With the ever-evolving threat landscape, research into innovative security measures is essential to ensure the integrity, confidentiality, and availability of network resources in this dynamic and transformative technology, ultimately safeguarding the reliability and functionality of our interconnected world. This research presents a novel approach to enhancing security in Software-Defined Networking through the development of an initial Intrusion Detection System. The IDS offers a scalable solution, facilitating the transmission and storage of network traffic with robust support for failure recovery across multiple nodes. Additionally, an innovative analysis module incorporates artificial intelligence (AI) to predict the nature of network traffic, effectively distinguishing between malicious and benign data. The system integrates a diverse range of technologies and tools, enabling the processing and analysis of network traffic data from PCAP files, thus contributing to the reinforcement of SDN security.As tecnologias de Redes Definidas por Software representam um paradigma recente na gestão de redes, oferecendo flexibilidade e escalabilidade sem precedentes. À medida que a adoção de soluções SDN continuam a crescer, também aumenta a urgência de estudar métodos para melhorar a sua segurança. É de extrema importância compreender e fortalecer a segurança das SDN, dado o seu papel fundamental no ecossistema digital moderno. Com o cenário de ameaças em constante evolução, a investigação de medidas de segurança inovadoras é essencial para garantir a integridade, a confidencialidade e a disponibilidade dos recursos da rede nesta tecnologia dinâmica e transformadora. Esta investigação apresenta uma nova abordagem para melhorar a segurança nas redes definidas por software através do desenvolvimento de um sistema inicial de deteção de intrusões. O IDS oferece uma solução escalável, facilitando a transmissão e o armazenamento do tráfego de rede com suporte robusto para recuperação de falhas em vários nós. Além disso, um módulo de análise inovador incorpora inteligência artificial (IA) para prever a natureza do tráfego de rede, distinguindo efetivamente entre dados maliciosos e benignos. O sistema integra uma gama diversificada de tecnologias e ferramentas, permitindo o processamento e a análise de dados de tráfego de rede a partir de ficheiros PCAP, contribuindo assim para o reforço da segurança SDN

Routing Security Issues in Wireless Sensor Networks: Attacks and Defenses

Wireless Sensor Networks (WSNs) are rapidly emerging as an important new area in wireless and mobile computing research. Applications of WSNs are numerous and growing, and range from indoor deployment scenarios in the home and office to outdoor deployment scenarios in adversary's territory in a tactical battleground (Akyildiz et al., 2002). For military environment, dispersal of WSNs into an adversary's territory enables the detection and tracking of enemy soldiers and vehicles. For home/office environments, indoor sensor networks offer the ability to monitor the health of the elderly and to detect intruders via a wireless home security system. In each of these scenarios, lives and livelihoods may depend on the timeliness and correctness of the sensor data obtained from dispersed sensor nodes. As a result, such WSNs must be secured to prevent an intruder from obstructing the delivery of correct sensor data and from forging sensor data. To address the latter problem, end-to-end data integrity checksums and post-processing of senor data can be used to identify forged sensor data (Estrin et al., 1999; Hu et al., 2003a; Ye et al., 2004). The focus of this chapter is on routing security in WSNs. Most of the currently existing routing protocols for WSNs make an optimization on the limited capabilities of the nodes and the application-specific nature of the network, but do not any the security aspects of the protocols. Although these protocols have not been designed with security as a goal, it is extremely important to analyze their security properties. When the defender has the liabilities of insecure wireless communication, limited node capabilities, and possible insider threats, and the adversaries can use powerful laptops with high energy and long range communication to attack the network, designing a secure routing protocol for WSNs is obviously a non-trivial task.Comment: 32 pages, 5 figures, 4 tables 4. arXiv admin note: substantial text overlap with arXiv:1011.152

Impact of denial of service solutions on network quality of service

The Internet has become a universal communication network tool. It has evolved from a platform that supports best-effort traffic to one that now carries different traffic types including those involving continuous media with quality of service (QoS) requirements. As more services are delivered over the Internet, we face increasing risk to their availability given that malicious attacks on those Internet services continue to increase. Several networks have witnessed denial of service (DoS) and distributed denial of service (DDoS) attacks over the past few years which have disrupted QoS of network services, thereby violating the Service Level Agreement (SLA) between the client and the Internet Service Provider (ISP). Hence DoS or DDoS attacks are major threats to network QoS. In this paper we survey techniques and solutions that have been deployed to thwart DoS and DDoS attacks and we evaluate them in terms of their impact on network QoS for Internet services. We also present vulnerabilities that can be exploited for QoS protocols and also affect QoS if exploited. In addition, we also highlight challenges that still need to be addressed to achieve end-to-end QoS with recently proposed DoS/DDoS solutions

Recent Trends in Communication Networks

In recent years there has been many developments in communication technology. This has greatly enhanced the computing power of small handheld resource-constrained mobile devices. Different generations of communication technology have evolved. This had led to new research for communication of large volumes of data in different transmission media and the design of different communication protocols. Another direction of research concerns the secure and error-free communication between the sender and receiver despite the risk of the presence of an eavesdropper. For the communication requirement of a huge amount of multimedia streaming data, a lot of research has been carried out in the design of proper overlay networks. The book addresses new research techniques that have evolved to handle these challenges

Automated performance attack discovery in distributed system implementations

Security and performance are critical goals for distributed systems. The increased complexity in design, incomplete expertise of developers, and limited functionality of existing testing tools often result in implementations with vulnerabilities and make the debugging process difficult and costly. The deployed vulnerabilities are often exploited by adversaries preventing the system from achieving its design goals. We refer to attacks that slow down the performance of a system as performance attacks. In the past, finding performance attacks has been a painstaking manual process that involved an expert of the target implementation. Given the cost associated with each vulnerability that occurs in the production, there is a need for tools to automatically check that the implementation of a protocol achieves its performance goals with respect to malicious components in the system. In this dissertation, we find performance attacks automatically from implementations of distributed systems. We do not try to show that an implementation is free from all attacks. Our goal is to find attacks and report them to the user in a timely manner. We first investigate how to find attacks automatically from implementations under a simulated environment. A simulated approach, however, has a fundamental limitation in terms of applicable target systems, as certain assumptions are made about languages, operating systems or libraries used. Therefore, we next investigate challenges and requirements to automatically find attacks in implementations of distributed systems under an emulated environment where no limiting assumptions are made

Dynamic Interactions for Network Visualization and Simulation

Most network visualization suites do not interact with a simulator, as it executes. Nor do they provide an effective user interface that includes multiple visualization functions. The subject of this research is to improve the network visualization presented in the previous research [5] adding these capabilities to the framework. The previous network visualization did not have the capability of altering specific visualization characteristics, especially when detailed observations needed to be made for a small part of a large network. Searching for a network event in this topology might cause large delays leading to lower quality user interface. In addition to shortfalls in handling complex network events, [5] did not provide dynamic user interactions since it did not have real-time interaction with a simulator. These shortfalls motivate the development of a new network visualization framework design that provides a more robust user interface, network observation tools and an interaction with the simulator. Our research presents the design, development and implementation of this new network visualization framework to enhance network scenarios and provide interaction with NS-2, as it executes. From the interface design perspective, this research presents a prototype design to ease the implementation process of the framework. The visualization functions such as clustering, filtering, labeling and color coding help accessing network objects and events, supporting four tabs consisting of buttons, menus, and sliders. The new network visualization framework design gives the ability to handle the inherent complexity of large networks, allowing the user to interact with the current display of the framework, alter visualization parameters and control the network through the visualization. In our application, multiple visualizations are linked to NS-2 to build execution scenarios which let to test clustering, filtering, labeling functionalities on separate visualization screens, as NS-2 progresses