104,587 research outputs found

    A general purpose programming framework for ubiquitous computing environments

    Get PDF
    It is important to note that the need to support ad-hoc and potentially mobile arrangements of devices in ubiquitous environments does not fit well within the traditional client/server architecture. We believe peer-to-peer communication offers a preferable alternative due to its decentralised nature, removing dependence on individual nodes. However, this choice adds to the complexity of the developers task. In this paper, we describe a two-tiered approach to address this problem: A lower tier employing peer-to-peer interactions for managing the network infrastructure and an upper tier providing a mobile agent based programming framework. The result is a general purpose framework for developing ubiquitous applications and services, where the underlying complexity is hidden from the developer. This paper discusses our on-going work; presenting our design decisions, features supported by our framework, and some of the challenges still to be addressed in a complex programming environment

    Peer-to-Peer Secure Updates for Heterogeneous Edge Devices

    Get PDF
    We consider the problem of securely distributing software updates to large scale clusters of heterogeneous edge compute nodes. Such nodes are needed to support the Internet of Things and low-latency edge compute scenarios, but are difficult to manage and update because they exist at the edge of the network behind NATs and firewalls that limit connectivity, or because they are mobile and have intermittent network access. We present a prototype secure update architecture for these devices that uses the combination of peer-to-peer protocols and automated NAT traversal techniques. This demonstrates that edge devices can be managed in an environment subject to partial or intermittent network connectivity, where there is not necessarily direct access from a management node to the devices being updated

    LD: Identifying Misbehaving Nodes in MANET

    Get PDF
    A mobile ad-hoc network is a collection of mobile nodes connected together over a wireless medium without any fixed infrastructure. Unique characteristics of mobile ad-hoc networks such as open peer-to-peer network architecture, shared wireless medium and highly dynamic topology, pose various challenges to the security design. Mobile ad-hoc networks lack central administration or control, making them very vulnerable to attacks or disruption by faulty nodes in the absence of any security mechanisms. Also, the wireless channel in a mobile ad-hoc network is accessible to both legitimate network users and malicious attackers. So, the task of finding good solutions for these challenges plays a critical role in achieving the eventual success of mobile ad-hoc networks. However, the open medium and wide distribution of nodes make MANET vulnerable to malicious attackers. In this case, it is crucial to develop efficient intrusion-detection mechanisms to protect MANET from attacks. Secure routing protocols and mechanisms to detect routing misbehavior in the direct neighborhood exist; however, collusion of misbehaving nodes has not been adequately addressed yet. We present LeakDetector, a mechanism to detect colluding malicious nodes in wireless multihop networks A mobile ad-hoc network is a collection of mobile nodes connected together over a wireless medium without any fixed infrastructure. Unique characteristics of mobile ad-hoc networks such as open peer-to-peer network architecture, shared wireless medium and highly dynamic topology, pose various challenges to the security design. Mobile ad-hoc networks lack central administration or control, making them very vulnerable to attacks or disruption by faulty nodes in the absence of any security mechanisms. Also, the wireless channel in a mobile ad-hoc network is accessible to both legitimate network users and malicious attackers. So, the task of finding good solutions for these challenges plays a critical role in achieving the eventual success of mobile ad-hoc networks. However,the. LeakDetector enables the calculation of the packet-loss ratio for the individual nodes

    Data dissemination strategies for mobile peer-to-peer information systems with applications to healthcare

    Get PDF
    Ankara : The Department of Computer Engineering and the Institute of Engineering and Science of Bilkent University, 2009.Thesis (Master's) -- Bilkent University, 2009.Includes bibliographical references leaves 64-69.Peer-to-peer (P2P) architecture is becoming increasingly popular for various applications, replacing the classical Client-Server architecture. With the enhanced capabilities of mobile devices (PDAs, mobile phones, etc.) wireless networks started to take advantage of P2P paradigm along with its properties like infrastructure-free operation, scalability, balanced and distributed workload. Mobile peer-to-peer (MP2P) networks refer to the application of P2P architecture over wireless networks. Problems about dissemination of data in both P2P and MP2P networks are widely studied, and there are many proposed solutions. Healthcare information systems are helping clinicians to hold the information belonging to patients and diseases, and to communicate with each other since early 1950s. Today, they are widely used in hospitals, being constructed using Client-Server network architecture. Wireless technologies are also applied to medical domain, especially for monitoring purposes. In this thesis, we present and evaluate various data dissemination strategies to work on a mobile peer-to-peer (MP2P) network designed for a medical healthcare environment. First, the designed network system is presented along with the network topology. Then, the proposed data dissemination strategies are described. And finally, these strategies are evaluated according to the properties and needs of a medical system.Özbekoğlu, Fatih MelihM.S

    Profile-Based Ad Hoc Social Networking Using Wi-Fi Direct on the Top of Android

    Get PDF
    Ad-hoc Social Networks have become popular to support novel applications related to location-based mobile services that are of great importance to users and businesses. Unlike traditional social services using a centralized server to fetch location, ad-hoc social network services support infrastructure less real-time social networking. It allows users to collaborate and share views anytime anywhere. However, current ad-hoc social network applications are either not available without rooting the mobile phones or don't filter the nearby users based on common interests without a centralized server. This paper presents an architecture and implementation of social networks on commercially available mobile devices that allow broadcasting name and a limited number of keywords representing users' interests without any connection in a nearby region to facilitate matching of interests. The broadcasting region creates a digital aura and is limited by WiFi region that is around 200 meters. The application connects users to form a group based on their profile or interests using peer-to-peer communication mode without using any centralized networking or profile matching infrastructure. The peer-to-peer group can be used for private communication when the network is not available

    Key-value storage system synchronization in peer-to-peer environments

    Get PDF
    Data synchronization is the problem of bringing multiple versions of the same data on different remote devices to the most up to date version. This thesis looks into the particular problem of key-value storage systems synchronization between mobile devices in a peer-to-peer environment. In this research, we describe, implement and evaluate a new key-value storage system synchronization algorithm using a 2-phase approach, combining approximate synchronization in the first phase and exact synchronization in the second phase. The 2-phase architecture helps the algorithm achieve considerable boost in performance in all three major criteria of a data synchronization algorithm, namely synchronization time, processing time and communication cost, while still being suitable to operate in a peer-to-peer environment. The performance increase makes it feasible to employ database synchronization technique in a wider range of mobile applications, especially those operating on a slow peer-to-peer network
    corecore