32,779 research outputs found

    FRIENDS - A flexible architecture for implementing fault tolerant and secure distributed applications

    Get PDF
    FRIENDS is a software-based architecture for implementing fault-tolerant and, to some extent, secure applications. This architecture is composed of sub-systems and libraries of metaobjects. Transparency and separation of concerns is provided not only to the application programmer but also to the programmers implementing metaobjects for fault tolerance, secure communication and distribution. Common services required for implementing metaobjects are provided by the sub-systems. Metaobjects are implemented using object-oriented techniques and can be reused and customised according to the application needs, the operational environment and its related fault assumptions. Flexibility is increased by a recursive use of metaobjects. Examples and experiments are also described

    A metaobject architecture for fault-tolerant distributed systems : the FRIENDS approach

    Get PDF
    The FRIENDS system developed at LAAS-CNRS is a metalevel architecture providing libraries of metaobjects for fault tolerance, secure communication, and group-based distributed applications. The use of metaobjects provides a nice separation of concerns between mechanisms and applications. Metaobjects can be used transparently by applications and can be composed according to the needs of a given application, a given architecture, and its underlying properties. In FRIENDS, metaobjects are used recursively to add new properties to applications. They are designed using an object oriented design method and implemented on top of basic system services. This paper describes the FRIENDS software-based architecture, the object-oriented development of metaobjects, the experiments that we have done, and summarizes the advantages and drawbacks of a metaobject approach for building fault-tolerant system

    Source Authentication for Multicast in Mobile Ad hoc Networks

    Get PDF
    Recent emergence and popularity of mobile ad hoc networks in a host of current-day applications has instigated a suite of research challenges, primarily in routing and security issues for such networks. The ease and low cost of deployment make this networking paradigm very convenient for group-oriented applications like battlefield missions, business conference, virtual classroom, etc. Such networks are characterized by wireless ``links'', lack of any fixed network infrastructure, rapidly changing topology and mobile hosts. Security for these dynamic ad hoc networks presents many challenges in the area of multicasting for group-oriented tactical missions, operating in a hostile environment. Key-management and secure-routing have been the primary research focus in this area. Source authentication for multicast is also a fundamental problem that needs to be addressed. In this work, we study some of the proposed source authentication schemes for multicast group communication and evaluate one such scheme for a tactical ad hoc set-up. We propose solutions that exploit the hierarchical nature of tactical networks to achieve time synchronization pre-requisites that the proposed schemes have. We define metrics to evaluate the authentication scheme and present simulation results for the authentication scheme evaluated with two different time synchronization techniques. We find that our selected authentication scheme is well suited for a mobile ad hoc network. We show that our solution for time synchronization performs much better than conventional methods suggested for the authentication scheme. We also discuss applications of our overlay architecture for bootstrapping the authentication scheme with reduced communication overhead

    Options for Securing RTP Sessions

    Get PDF
    The Real-time Transport Protocol (RTP) is used in a large number of different application domains and environments. This heterogeneity implies that different security mechanisms are needed to provide services such as confidentiality, integrity, and source authentication of RTP and RTP Control Protocol (RTCP) packets suitable for the various environments. The range of solutions makes it difficult for RTP-based application developers to pick the most suitable mechanism. This document provides an overview of a number of security solutions for RTP and gives guidance for developers on how to choose the appropriate security mechanism

    The Clarens web services architecture

    Get PDF
    Clarens is a uniquely flexible web services infrastructure providing a unified access protocol to a diverse set of functions useful to the HEP community. It uses the standard HTTP protocol combined with application layer, certificate based authentication to provide single sign-on to individuals, organizations and hosts, with fine-grained access control to services, files and virtual organization (VO) management. This contribution describes the server functionality, while client applications are described in a subsequent talk.Comment: Talk from the 2003 Computing in High Energy and Nuclear Physics (CHEP03), La Jolla, Ca, USA, March 2003, 6 pages, LaTeX, 4 figures, PSN MONT00

    A Survey on Wireless Security: Technical Challenges, Recent Advances and Future Trends

    Full text link
    This paper examines the security vulnerabilities and threats imposed by the inherent open nature of wireless communications and to devise efficient defense mechanisms for improving the wireless network security. We first summarize the security requirements of wireless networks, including their authenticity, confidentiality, integrity and availability issues. Next, a comprehensive overview of security attacks encountered in wireless networks is presented in view of the network protocol architecture, where the potential security threats are discussed at each protocol layer. We also provide a survey of the existing security protocols and algorithms that are adopted in the existing wireless network standards, such as the Bluetooth, Wi-Fi, WiMAX, and the long-term evolution (LTE) systems. Then, we discuss the state-of-the-art in physical-layer security, which is an emerging technique of securing the open communications environment against eavesdropping attacks at the physical layer. We also introduce the family of various jamming attacks and their counter-measures, including the constant jammer, intermittent jammer, reactive jammer, adaptive jammer and intelligent jammer. Additionally, we discuss the integration of physical-layer security into existing authentication and cryptography mechanisms for further securing wireless networks. Finally, some technical challenges which remain unresolved at the time of writing are summarized and the future trends in wireless security are discussed.Comment: 36 pages. Accepted to Appear in Proceedings of the IEEE, 201
    • …
    corecore