Unoma Ndili Okorafor

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For very low power, high bandwidth applications, free space optical sensor networks (FSOSN) have shown potential. They promise increasing node functionality, lower energy consumption, lower cost and smaller sizes. However, the new optical communication architecture yields new routing challenges. The objective of our paper is to introduce novel routing(More)
There is a critical need to provide privacy and security assurances for distributed multimedia sensor networking in applications including military surveillance and healthcare monitoring. Such guarantees enable the widespread adoption of such information systems, leading to large-scale societal benefit. To effectively address protection and reliability(More)
In this paper we introduce OPSENET, a novel and efficient protocol that facilitates secure routing in directional optical sensor networks. We show that even though the uni- directionality of links in an optical sensor network (OSN) complicates the design of efficient routing, link directionality actually helps security in our network setup. In particular,(More)
In this paper, we investigate the fundamental property of connectivity in a hierarchical ad-hoc optical sensor network (OSN) communicating with broad beam lasers. The OSN is modeled as a random sector graph, in which the randomly deployed sensors can send data within a contiguous and randomly oriented sector of communication. Hierarchy is achieved by(More)
In this paper we evaluate the energy and security consideration for a security-aware routing protocol proposed for uni-directional, hierarchical optical sensor network. We bootstrap the unconstrained resources of the base station to design GORA, a greedy optimized routing algorithm, in which the base station is responsible for network route optimization and(More)
This paper introduces a novel "HoLiSTiC" framework for visual sensor networks (VisSNs) and studies security issues within this context. The HoLiSTiC paradigm, which encompasses many existing VisSN proposals, effectively exploits heterogeneous wireless sensing and communications for more flexible, practical and scalable visual surveillance. Security aspects(More)
In designing wireless multihop sensor networks, determining system parameters that guarantee a reasonably connected network is crucial. In this paper, we investigate node isolation in wireless optical sensor networks (WOSNs) as a topology attribute for network connectivity. Our results pertain to WOSNs modeled as random-scaled sector graphs that employ(More)
The existing routing protocols in mobile ad hoc network such as DSDV, AODV, DSR, ZRP, SRL, HSR, etc cannot be utilized for FSO/RF MANET owing to certain disjoint characteristics of free space optical (FSO) and MANET. The characteristics include accommodating directionality, accuracy in routing information, memory, reduced overhead and delay. In this paper,(More)
There has been recent interest in the development of untethered sensor nodes that communicate directionally via free space optical communications for mission critical settings in which high-speed link guarantees in hostile environments are needed. Directional wireless optical sensor networks have the potential to provide gigabits per second speeds for(More)