Hongsik Choi

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Network survivability is a crucial requirement in high-speed optical networks. Typical approaches of providing survivability have considered the failure of a single component such as a link or a node. In this paper, we consider a failure model in which any two links in the network may fail in an arbitrary order. Three loopback methods of recovering from(More)
Summary form only given. As the energy consumption in wireless sensor nodes is dominated by the radio transmission circuitry, the network configuration must be designed to minimize the power consumption by transmission radios. Sensor nodes are generally equipped with short-range radios that require low power consumption. But the current technology allows(More)
We investigate a unique wireless sensor network scheduling problem in which all nodes in a cluster send exactly one packet to a designated sink node in an effort to minimize transmission time. However, node transmissions must be sufficiently isolated either in time or in space to avoid collisions. The problem is formulated and solved via graph(More)
Network survivability is a crucial requirement in high-speed optical networks. Typical approaches of providing survivability have considered the failure of a single component such as a link or a node. In this paper, we motivate the need for considering double-link failures and present three loopback methods for handling such failures. In the first two(More)
We studied the possibility of using wireless sensor networks for vehicle identification in a large open field. This is exciting research in that it not only presents a challenge but has practicality. The challenge here is to develop algorithms and/or protocols for sensor nodes to execute a given task. Since each sensor node has limited computation and(More)
We investigate a unique scheduling problem in wireless sensor networks where all nodes in a cluster send exactly one packet to a designated sink node with goal of minimized transmission time. The difficulty lies in the fact that node transmissions must be sufficiently isolated either in time or in space to avoid collisions. The problem is formulated and(More)
Achieving accurate and efficient fault localization in large transparent all-optical networks (TONs) is an important and challenging problem due to unique fault-propagation, time constraints, and scalability requirements. In this paper, we introduce a novel technique for optimizing the speed of fault-localization through the selection of an active set of(More)
This paper is concerned with optimal transmission schedules in the TWDM (time and wavelength division multiplexed) optical passive star network. Our model of the network consists of a set V of N nodes with N tunable transmitters and N fixed-tuned receivers (where each node is assigned a transmitter-receiver pair), k wavelengths (each wavelength is shared by(More)