3,405 research outputs found

    IP-based virtual private networks and proportional quality of service differentiation

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    IP-based virtual private networks (VPNs) have the potential of delivering cost-effective, secure, and private network-like services. Having surveyed current enabling techniques, an overall picture of IP VPN implementations is presented. In order to provision the equivalent quality of service (QoS) of legacy connection-oriented layer 2 VPNs (e.g., Frame Relay and ATM), IP VPNs have to overcome the intrinsically best effort characteristics of the Internet. Subsequently, a hierarchical QoS guarantee framework for IP VPNs is proposed, stitching together development progresses from recent research and engineering work. To differentiate IP VPN QoS, the proportional QoS differentiation model, whose QoS specification granularity compromises that of IntServ and Diffserv, emerges as a potential solution. The investigation of its claimed capability of providing the predictable and controllable QoS differentiation is then conducted. With respect to the loss rate differentiation, the packet shortage phenomenon shown in two classical proportional loss rate (PLR) dropping schemes is studied. On the pursuit of a feasible solution, the potential of compromising the system resource, that is, the buffer, is ruled out; instead, an enhanced debt-aware mechanism is suggested to relieve the negative effects of packet shortage. Simulation results show that debt-aware partially curbs the biased loss rate ratios, and improves the queueing delay performance as well. With respect to the delay differentiation, the dynamic behavior of the average delay difference between successive classes is first analyzed, aiming to gain insights of system dynamics. Then, two classical delay differentiation mechanisms, that is,proportional average delay (PAD) and waiting time priority (WTP), are simulated and discussed. Based on observations on their differentiation performances over both short and long time periods, a combined delay differentiation (CDD) scheme is introduced. Simulations are utilized to validate this method. Both loss and delay differentiations are based on a series of differentiation parameters. Though previous work on the selection of delay differentiation parameters has been presented, that of loss differentiation parameters mostly relied on network operators\u27 experience. A quantitative guideline, based on the principles of queueing and optimization, is then proposed to compute loss differentiation parameters. Aside from analysis, the new approach is substantiated by numerical results

    Toward an RSU-unavailable lightweight certificateless key agreement scheme for VANETs

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    Vehicle ad-hoc networks have developed rapidly these years, whose security and privacy issues are always concerned widely. In spite of a remarkable research on their security solutions, but in which there still lacks considerations on how to secure vehicle-to-vehicle communications, particularly when infrastructure is unavailable. In this paper, we propose a lightweight certificateless and one-round key agreement scheme without pairing, and further prove the security of the proposed scheme in the random oracle model. The proposed scheme is expected to not only resist known attacks with less computation cost, but also as an efficient way to relieve the workload of vehicle-to-vehicle authentication, especially in no available infrastructure circumstance. A comprehensive evaluation, including security analysis, efficiency analysis and simulation evaluation, is presented to confirm the security and feasibility of the proposed scheme

    Receiver-driven routing for community mesh networks

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    Community wireless mesh networks are decentralized and cooperative structures with participation rules that define their freedom, openness and neutrality. The operation of these networks require routing algorithms that may impose additional unnecessary technical restrictions in the determination of routes that can restrict the freedom of community users. We propose a receiver-driven discretionary routing mechanism where each receiver (the intended destination of the packet) can freely specify delivery objectives and remain compatible with the collaborative approach of community networks. Each node has a unique identifier and can announce the description of its offer and also the description of its routing policy with preferences to deliver traffic to it. BMX6 provides a 'hash-based profile propagation mechanism' to disseminate descriptions. This receiver-driven routing can be applied to express preferences for desirable nodes and paths, or to restrict traffic to trusted nodes enabling trust and security aware routing. We validate our contributions with a proof of concept implementation of key concepts, as an extension of the BMX6 routing protocol, that confirms its feasibility and scalability.Postprint (author’s final draft

    Analysis for Resource Utilization in Cloud Computing-A Survey

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    Distributed or cloud computing depends on sharing of processing assets subsequently boosting the economy. The assets shared together are utilized distinctively among various customer/client gatherings and structure an alternate example of asset usage. In this paper different methods for distinguishing customer/client standard of conduct for asset usage are examined. This examination will configuration cloud administrations as per the customer/client practices designs for usage of assets in distributed computing

    A Trusted and Privacy-preserving Internet of Mobile Energy

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    The rapid growth in distributed energy sources on power grids leads to increasingly decentralised energy management systems for the prediction of power supply and demand and the dynamic setting of an energy price signal. Within this emerging smart grid paradigm, electric vehicles can serve as consumers, transporters, and providers of energy through two-way charging stations, which highlights a critical feedback loop between the movement patterns of these vehicles and the state of the energy grid. This paper proposes a vision for an Internet of Mobile Energy (IoME), where energy and information flow seamlessly across the power and transport sectors to enhance the grid stability and end user welfare. We identify the key challenges of trust, scalability, and privacy, particularly location and energy linking privacy for EV owners, for realising the IoME vision. We propose an information architecture for IoME that uses scalable blockchain to provide energy data integrity and authenticity, and introduces one-time keys for public EV transactions and a verifiable anonymous trip extraction method for EV users to share their trip data while protecting their location privacy. We present an example scenario that details the seamless and closed loop information flow across the energy and transport sectors, along with a blockchain design and transaction vocabulary for trusted decentralised transactions. We finally discuss the open challenges presented by IoME that can unlock significant benefits to grid stability, innovation, and end user welfare.Comment: 7 pages, 5 figure

    Efficient Key Management Schemes for Smart Grid

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    With the increasing digitization of different components of Smart Grid by incorporating smart(er) devices, there is an ongoing effort to deploy them for various applications. However, if these devices are compromised, they can reveal sensitive information from such systems. Therefore, securing them against cyber-attacks may represent the first step towards the protection of the critical infrastructure. Nevertheless, realization of the desirable security features such as confidentiality, integrity and authentication relies entirely on cryptographic keys that can be either symmetric or asymmetric. A major need, along with this, is to deal with managing these keys for a large number of devices in Smart Grid. While such key management can be easily addressed by transferring the existing protocols to Smart Grid domain, this is not an easy task, as one needs to deal with the limitations of the current communication infrastructures and resource-constrained devices in Smart Grid. In general, effective mechanisms for Smart Grid security must guarantee the security of the applications by managing (1) key revocation; and (2) key exchange. Moreover, such management should be provided without compromising the general performance of the Smart Grid applications and thus needs to incur minimal overhead to Smart Grid systems. This dissertation aims to fill this gap by proposing specialized key management techniques for resource and communication constrained Smart Grid environments. Specifically, motivated by the need of reducing the revocation management overhead, we first present a distributed public key revocation management scheme for Advanced Metering Infrastructure (AMI) by utilizing distributed hash trees (DHTs). The basic idea is to enable sharing of the burden among smart meters to reduce the overall overhead. Second, we propose another revocation management scheme by utilizing cryptographic accumulators, which reduces the space requirements for revocation information significantly. Finally, we turn our attention to symmetric key exchange problem and propose a 0-Round Trip Time (RTT) message exchange scheme to minimize the message exchanges. This scheme enables a lightweight yet secure symmetric key-exchange between field devices and the control center in Smart Gird by utilizing a dynamic hash chain mechanism. The evaluation of the proposed approaches show that they significantly out-perform existing conventional approaches
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