57 research outputs found

    A pragmatic approach: Achieving acceptable security mechanisms for high speed data transfer protocol-UDT

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    The development of next generation protocols, such as UDT (UDP-based data transfer), promptly addresses various infrastructure requirements for transmitting data in high speed networks. However, this development creates new vulnerabilities when these protocols are designed to solely rely on existing security solutions of existing protocols such as TCP and UDP. It is clear that not all security protocols (such as TLS) can be used to protect UDT, just as security solutions devised for wired networks cannot be used to protect the unwired ones. The development of UDT, similarly in the development of TCP/UDP many years ago, lacked a well-thought security architecture to address the problems that networks are presently experiencing. This paper proposes and analyses practical security mechanisms for UDT

    Detecting and Isolating Distributed Denial of Service attack in Smart Grid Systems

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    Smart grid, which is considered as next generation power grid is an two way connected power system framework which enables easy monitoring and maintenance of power systems when compared to the existing power systems. Smart grid is also called as electrical grid or intelligent grid is an enhancement of 20th century power grid. Smart grid technically depends upon the network protocol and the topology over which it is constructed. Hence like the conventional connected systems, smart grid is also prone to number of security threats like Eavesdropping attack, data alteration attack, identity spoofing attack, compromised key attack, replay attack and distributed denial of service (DDOS) attack. In-spite of providing good technology to all the connected systems, there are frequent security breaches like DDOS attack which will extremely influence the availability of smart grid framework. Attacks targeting the availability like DDOS attack are the interruption of access or use of information which may further disrupt the power delivery. This thesis discusses detection and isolation of DDOS attack on Smart Grid. We have proposed three techniques to protect the framework against DDOS attack utilizing Marking system, TTL Value investigation and MAC value examination. The analysis of marking scheme has been carried out on Network Simulator Version 2. The identification of fake packets has been carried out using TTL value with help of Cisco packet tracer, cola soft packet builder and Snort Intrusion detection tool. The uniqueness of the MAC address and IP address are matched with the help of Arpwatch tool and Snort Intrusion detection tool to detect the fake MAC and IP address pair. With these schemes it is possible to pro-actively prevent the DDOS attack

    Congestion control algorithms of TCP in emerging networks

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    In this dissertation we examine some of the challenges faced by the congestion control algorithms of TCP in emerging networks. We focus on three main issues. First, we propose TCP with delayed congestion response (TCP-DCR), for improving performance in the presence of non-congestion events. TCP-DCR delays the conges- tion response for a short interval of time, allowing local recovery mechanisms to handle the event, if possible. If at the end of the delay, the event persists, it is treated as congestion loss. We evaluate TCP-DCR through analysis and simulations. Results show significant performance improvements in the presence of non-congestion events with marginal impact in their absence. TCP-DCR maintains fairness with standard TCP variants that respond immediately. Second, we propose Layered TCP (LTCP), which modifies a TCP flow to behave as a collection of virtual flows (or layers), to improve eficiency in high-speed networks. The number of layers is determined by dynamic network conditions. Convergence properties and RTT-unfairness are maintained similar to that of TCP. We provide the intuition and the design for the LTCP protocol and evaluation results based on both simulations and Linux implementation. Results show that LTCP is about an order of magnitude faster than TCP in utilizing high bandwidth links while maintaining promising convergence properties. Third, we study the feasibility of employing congestion avoidance algorithms in TCP. We show that end-host based congestion prediction is more accurate than previously characterized. However, uncertainties in congestion prediction may be un- avoidable. To address these uncertainties, we propose an end-host based mechanism called Probabilistic Early Response TCP (PERT). PERT emulates the probabilistic response function of the router-based scheme RED/ECN in the congestion response function of the end-host. We show through extensive simulations that, similar to router-based RED/ECN, PERT provides fair bandwidth sharing with low queuing delays and negligible packet losses, without requiring the router support. It exhibits better characteristics than TCP-Vegas, the illustrative end-host scheme. PERT can also be used for emulating other router schemes. We illustrate this through prelim- inary results for emulating the router-based mechanism REM/ECN. Finally, we show the interactions and benefits of combining the different proposed mechanisms

    Achieving Soft Real-time Guarantees for Interactive Applications in Wireless Mesh Networks

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    The use of 802.11-based multi-hop wireless mesh networks for Internet access is extensive and growing. The primary advantages of this approach are ease of deployment and lower cost. However, these networks are designed for web and e-mail applications. Highly interactive applications, such as multiplayer online games and VoIP, with their requirements for low delay, present significant challenges to these networks. In particular, the interaction between real-time traffic and TCP traffic tends to result in either a failure of the real-time traffic getting its needed QoS or the TCP traffic unnecessarily experiencing very poor throughput. To solve this problem we place real-time and TCP traffic into separate queues. We then rate-limit TCP traffic based on the average queue size of the local or remote real-time queues. Thus, TCP traffic is permitted to use excess bandwidth as long as it does not interfere with real-time traffic guarantees. We therefore call our scheme Real-time Queue-based Rate and Admission Control, RtQ-RAC. Extensive simulations using the network simulator, ns-2, demonstrate that our approach is effective in providing soft real-time support, while allowing efficient use of the remaining bandwidth for TCP traffic

    Mobile Ad Hoc Networks

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    Guiding readers through the basics of these rapidly emerging networks to more advanced concepts and future expectations, Mobile Ad hoc Networks: Current Status and Future Trends identifies and examines the most pressing research issues in Mobile Ad hoc Networks (MANETs). Containing the contributions of leading researchers, industry professionals, and academics, this forward-looking reference provides an authoritative perspective of the state of the art in MANETs. The book includes surveys of recent publications that investigate key areas of interest such as limited resources and the mobility of mobile nodes. It considers routing, multicast, energy, security, channel assignment, and ensuring quality of service. Also suitable as a text for graduate students, the book is organized into three sections: Fundamentals of MANET Modeling and Simulation—Describes how MANETs operate and perform through simulations and models Communication Protocols of MANETs—Presents cutting-edge research on key issues, including MAC layer issues and routing in high mobility Future Networks Inspired By MANETs—Tackles open research issues and emerging trends Illustrating the role MANETs are likely to play in future networks, this book supplies the foundation and insight you will need to make your own contributions to the field. It includes coverage of routing protocols, modeling and simulations tools, intelligent optimization techniques to multicriteria routing, security issues in FHAMIPv6, connecting moving smart objects to the Internet, underwater sensor networks, wireless mesh network architecture and protocols, adaptive routing provision using Bayesian inference, and adaptive flow control in transport layer using genetic algorithms

    A cross-layer middleware architecture for time and safety critical applications in MANETs

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    Mobile Ad hoc Networks (MANETs) can be deployed instantaneously and adaptively, making them highly suitable to military, medical and disaster-response scenarios. Using real-time applications for provision of instantaneous and dependable communications, media streaming, and device control in these scenarios is a growing research field. Realising timing requirements in packet delivery is essential to safety-critical real-time applications that are both delay- and loss-sensitive. Safety of these applications is compromised by packet loss, both on the network and by the applications themselves that will drop packets exceeding delay bounds. However, the provision of this required Quality of Service (QoS) must overcome issues relating to the lack of reliable existing infrastructure, conservation of safety-certified functionality. It must also overcome issues relating to the layer-2 dynamics with causal factors including hidden transmitters and fading channels. This thesis proposes that bounded maximum delay and safety-critical application support can be achieved by using cross-layer middleware. Such an approach benefits from the use of established protocols without requiring modifications to safety-certified ones. This research proposes ROAM: a novel, adaptive and scalable cross-layer Real-time Optimising Ad hoc Middleware framework for the provision and maintenance of performance guarantees in self-configuring MANETs. The ROAM framework is designed to be scalable to new optimisers and MANET protocols and requires no modifications of protocol functionality. Four original contributions are proposed: (1) ROAM, a middleware entity abstracts information from the protocol stack using application programming interfaces (APIs) and that implements optimisers to monitor and autonomously tune conditions at protocol layers in response to dynamic network conditions. The cross-layer approach is MANET protocol generic, using minimal imposition on the protocol stack, without protocol modification requirements. (2) A horizontal handoff optimiser that responds to time-varying link quality to ensure optimal and most robust channel usage. (3) A distributed contention reduction optimiser that reduces channel contention and related delay, in response to detection of the presence of a hidden transmitter. (4) A feasibility evaluation of the ROAM architecture to bound maximum delay and jitter in a comprehensive range of ns2-MIRACLE simulation scenarios that demonstrate independence from the key causes of network dynamics: application setting and MANET configuration; including mobility or topology. Experimental results show that ROAM can constrain end-to-end delay, jitter and packet loss, to support real-time applications with critical timing requirements

    Mobile Ad Hoc Networks

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    Guiding readers through the basics of these rapidly emerging networks to more advanced concepts and future expectations, Mobile Ad hoc Networks: Current Status and Future Trends identifies and examines the most pressing research issues in Mobile Ad hoc Networks (MANETs). Containing the contributions of leading researchers, industry professionals, and academics, this forward-looking reference provides an authoritative perspective of the state of the art in MANETs. The book includes surveys of recent publications that investigate key areas of interest such as limited resources and the mobility of mobile nodes. It considers routing, multicast, energy, security, channel assignment, and ensuring quality of service. Also suitable as a text for graduate students, the book is organized into three sections: Fundamentals of MANET Modeling and Simulation—Describes how MANETs operate and perform through simulations and models Communication Protocols of MANETs—Presents cutting-edge research on key issues, including MAC layer issues and routing in high mobility Future Networks Inspired By MANETs—Tackles open research issues and emerging trends Illustrating the role MANETs are likely to play in future networks, this book supplies the foundation and insight you will need to make your own contributions to the field. It includes coverage of routing protocols, modeling and simulations tools, intelligent optimization techniques to multicriteria routing, security issues in FHAMIPv6, connecting moving smart objects to the Internet, underwater sensor networks, wireless mesh network architecture and protocols, adaptive routing provision using Bayesian inference, and adaptive flow control in transport layer using genetic algorithms

    A hybrid rate control mechanism for forwarding and congestion control in named data network

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    Named Data Networking (NDN) is an emerging Internet architecture that employs a pull-based, in-path caching, hop-by-hop, and multi-path transport architecture. Therefore, transport algorithms which use conventional paradigms would not work correctly in the NDN environment, since the content source location frequently changes. These changes raise forwarding and congestion control problems, and they directly affect the link utilization, fairness, and stability of the network. This study proposes a Hybrid Rate Control Mechanism (HRCM) to control the forwarding rate and link congestion to enhance network scalability, stability, and fairness performance. HRCM consists of three schemes namely Shaping Deficit Weight Round Robin (SDWRR), Queue-delay Parallel Multipath (QPM), and Explicit Control Agile-based conservative window adaptation (EC-Agile). The SDWRR scheme is scheduling different flows in router interfaces by fairly detecting and notifying the link congestion. The QPM scheme has been designed to forward Interest packets to all available paths that utilize idle bandwidths. The EC-Agile scheme controls forwarding rates by examining each packet received. The proposed HRCM was evaluated by comparing it with two different mechanisms, namely Practical Congestion Control (PCON) and Hop-by-hop Interest Shaping (HIS) through ndnSIM simulation. The findings show that HRCM enhances the forwarding rate and fairness. HRCM outperforms HIS and PCON in terms of throughput by 75%, delay 20%, queue length 55%, link utilization 41%, fairness 20%, and download time 20%. The proposed HRCM contributes to providing an enhanced forwarding rate and fairness in NDN with different types of traffic flow. Thus, the SDWRR, QPM, and EC-Agile schemes can be used in monitoring, controlling, and managing congestion and forwarding for the Internet of the future

    Security-centric analysis and performance investigation of IEEE 802.16 WiMAX

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