Mohamed Tamer Refaei

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For ad hoc networks to realize their potential in commercial deployments, it is important that they incorporate adequate security measures. Selfish behavior of autonomous network nodes could greatly disrupt network operation. Such behavior should be discouraged, detected, and isolated. In this paper, we propose a reputation-based mechanism to detect and(More)
Ad hoc networks, such as sensor and mobile ad hoc networks, must overcome a myriad of security challenges to realize their potential in both civil and military applications. Typically, ad hoc networks are deployed in un-trusted environments. Consequently, authentication is a precursor to any secure interactions in these networks. Recently, numerous(More)
We propose a secure routing architecture for Mobile Ad hoc NETworks (MANETs) called ThroughpUt-Feedback (TUF) routing, which is resilient against a wide range of routing disruption Denial-of-Service (DoS) attacks. Unlike many existing solutions, TUF does not focus on a particular type of attack, but instead takes an approach that is fundamentally more(More)
Reputation management systems have been proposed as a cooperation enforcement solution in ad hoc networks. Typically, the functions of reputation management (evaluation, detection, and reaction) are carried out homogeneously across time and space. However, the dynamic nature of ad hoc networks causes node behavior to vary both spatially and temporally due(More)
In [1], we investigated the use of multi-hop relays (a.k.a. breadcrumbs) to extend the range of public safety communications in indoor environments where the radio propagation conditions are harsh or wireless communications are limited by distance. In this work, we consider the impact of interference on the reliability of the breadcrumb system. We develop a(More)
†Bradley Department of Electrical and Computer Engineering Virginia Tech Alexandria, VA 22314 {mtamer,ldasilva} *Department of Computer Science George Washington University Washington, DC 20052 { yxrong,hchoi} Abstract Ad hoc networks employ a decentralized unstructured networking model that relies on node cooperation for key network(More)
Mobile Ad hoc NETworks (MANETs) are decentralized environments comprised of mobile computing devices that interact among each other via multi-hop wireless links. MANET nodes forward packets on behalf of other nodes in the network. Such routing decisions are made autonomously by individual nodes. MANET characteristics make them highly vulnerable to a myriad(More)
Tactical communication environments are characterized by frequent disruptions, intermittent connectivity, and low bandwidth (DIL) due to the unfavorable, unfriendly, and sometimes very dynamic network conditions. Nevertheless, there is still an expectation that tactical applications can communicate seamlessly despite the challenging communication(More)
CDMA 1x Ev-DO is an evolution of the CDMA2000 3G wireless standard to enable high rate packet data services up to 2.4Mbps in Rev 0, 3.1Mbps in Rev A, and 4.9Mbps in Rev B. To support such high data rates, CDMA 1x Ev-DO utilizes TDMA technology on the downlink allowing a single receiver per time slot. Accordingly, a scheduling algorithm is necessary to(More)