This paper considers the design of multiuser opportunistic packet schedulers for users sharing a time-varying wireless channel from performance and robustness points of view. For a simplified model falling in the classical Markov decision process framework, we numerically compute and characterize mean-delay-optimal scheduling policies. The computed policies exhibit radial sum-rate monotonicity: As users’ queues grow […]
A Privacy-Preserving Location Monitoring System for Wireless Sensor Networks
Monitoring personal locations with a potentially untrusted server poses privacy threats to the monitored individuals. To this end, we propose a privacy-preserving location monitoring system for wireless sensor networks. In our system, we design two in-network location anonymization algorithms, namely, resource and quality-aware algorithms, that aim to enable the system to provide high-quality location monitoring […]
Efficient Data Collection in Wireless Sensor Networks with Path-Constrained Mobile Sinks
Recent work shows that sink mobility along a constrained path can improve the energy efficiency in wireless sensor networks. However, due to the path constraint, a mobile sink with constant speed has limited communication time to collect data from the sensor nodes deployed randomly. This poses significant challenges in simultaneously improving the amount of data […]
On Reliable Broadcast in Low Duty-Cycle Wireless Sensor Networks
Broadcast is one of the most fundamental services in wireless sensor networks, where a distinct feature is that sensor nodes may alternate between active and dormant states, so as to conserve energy and extend the network lifetime. Unfortunately, the impact of such cycles has been largely ignored in existing broadcast implementations that adopt the common […]
Fast Data Collection in Tree-Based Wireless Sensor Networks
We investigate the following fundamental question – how fast can information be collected from a wireless sensor network organized as tree? To address this, we explore and evaluate a number of techniques using realistic simulation models under the many-to-one communication paradigm known as convergecast. We first consider time scheduling on a single frequency channel with […]
Fault Localization Using Passive End-to-End Measurements and Sequential Testing for Wireless Sensor Networks
Faulty components in a network need to be localized and repaired to sustain the health of the network. In this paper, we propose a novel approach that carefully combines active and passive measurements to localize faults in wireless sensor networks. More specifically, we formulate a problem of optimal sequential testing guided by end-to-end data. This […]
Fast Detection of Mobile Replica Node Attacks in Wireless Sensor Networks Using Sequential Hypothesis Testing
Due to the unattended nature of wireless sensor networks, an adversary can capture and compromise sensor nodes, generate their replicas, and thus mount a variety of attacks with these replicas. Such attacks are dangerous because they allow the attacker to leverage the compromise of a few nodes to exert control over much of the network. […]
Transient Analysis of IEEE 802.15.4 Sensor Networks
We study the delay performance of a sensor network, whose nodes access the medium by using the unslotted MAC protocol specified by the IEEE 802.15.4 standard. Unlike previous works, which focus on the average throughput and delay analysis, we develop a detailed model that allows us to obtain the delivery delay distribution of messages sent […]
Computing Localized Power-Efficient Data Aggregation Trees for Sensor Networks
We propose localized, self organizing, robust, and energy-efficient data aggregation tree approaches for sensor networks,which we call Localized Power-Efficient Data Aggregation Protocols (L-PEDAPs). They are based on topologies, such as LMST and RNG,that can approximate minimum spanning tree and can be efficiently computed using only position or distance information of one-hopneighbors. The actual routing tree […]
Optimal Selective Forwarding for Energy Saving in Wireless Sensor Networks
Scenarios where nodes have limited energy and forward messages of different importances (priorities) are frequent in the context of wireless sensor networks.Tailored to those scenarios, this paper relies on stochastic tools to develop selective message forwarding schemes. The schemes will depend on parameters such as the available battery at the node, the energy cost of […]
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