Does the Overhead Ratio Measure Efficiency?

As a cooperative information system, vehicles in Vehicular Sensor Networks deliver messages based on collaboration. Due to the high speed of vehicles, the topology of the network is highly dynamic, and the network may be disconnected frequently. So how to transfer large files in such network is worth considering. The encountering nodes which never meet before flood messages blindly cause tremendous network overhead. We address this challenge by introducing the Encounter Utility Rank Router (EURR) based on social metrics. EURR includes three cases: Utility Replication Strategy, Lifetime Replication Strategy and SocialRank Replication Strategy. The Lifetime Replication is promising and complements Utility Replication. It enhances the delivery ratio by relaying the copy via the remaining lifetime. Considering the network overhead, the SocialRank Replication replicates a copy according to the SocialRank when two communicating nodes have not met before. The routing mechanism explores the utility of history encounter information and social opportunistic forwarding. The results under the scenario show an advantage of the proposed EURR over the compared algorithms in terms of delivery ratio, average delivery latency and overhead ratio.

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Independent Tests and the Log-Likelihood-Ratio Measure of Confirmation

Thought A Journal of Philosophy ◽

10.1002/tht3.120 ◽

2014 ◽

Vol 3 (2) ◽

pp. 124-135

Author(s):

Alexander R. Pruss

Keyword(s):

Likelihood Ratio ◽

Log Likelihood ◽

Log Likelihood Ratio ◽

Ratio Measure

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The Optimal Checkpoint Interval for the Long-Running Application

Research Anthology on Architectures, Frameworks, and Integration Strategies for Distributed and Cloud Computing ◽

10.4018/978-1-7998-5339-8.ch125 ◽

2021 ◽

pp. 2590-2599

Author(s):

Yongning Zhai ◽

Weiwei Li

Keyword(s):

Distributed Computing ◽

Performance Optimization ◽

Fault Tolerant ◽

Computing System ◽

Effective Rate ◽

Performance Degradation ◽

Numerical Results ◽

Failure Distribution ◽

Overhead Ratio

For the distributed computing system, excessive or deficient checkpointing operations would result in severe performance degradation. To minimize the expected computation execution of the long-running application with a general failure distribution, the optimal equidistant checkpoint interval for fault tolerant performance optimization is analyzed and derived in this paper. More precisely, the optimal checkpointing period to determine the proper checkpoint sequence is proposed, and the derivation of the expected effective rate of the defined computation cycle is introduced. Corresponding to the maximal expected effective rate, the constraint of the optimal checkpoint sequence can be obtained. From the constraint of optimality, the optimal equidistant checkpoint interval can be obtained according to the minimal fault tolerant overhead ratio. By the numerical results, the proposal is practical to determine a proper equidistant checkpoint interval for fault tolerant performance optimization.

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A novel energy-aware routing protocol in intermittently connected delay-tolerant wireless sensor networks

International Journal of Distributed Sensor Networks ◽

10.1177/1550147717717389 ◽

2017 ◽

Vol 13 (7) ◽

pp. 155014771771738 ◽

Cited By ~ 4

Author(s):

Min Wook Kang ◽

Yun Won Chung

Keyword(s):

Wireless Sensor Networks ◽

Sensor Networks ◽

Routing Protocol ◽

Wireless Sensor ◽

Energy Aware ◽

Probabilistic Routing ◽

History Of ◽

Delay Tolerant ◽

Overhead Ratio ◽

Intermittently Connected

In delay-tolerant wireless sensor networks, messages for sensor data are delivered using opportunistic contacts between intermittently connected nodes. Since there is no stable end-to-end routing path like the Internet and mobile nodes operate on battery, an energy-efficient routing protocol is needed. In this article, we consider the probabilistic routing protocol using history of encounters and transitivity protocol as the base protocol. Then, we propose an energy-aware routing protocol in intermittently connected delay-tolerant wireless sensor networks, where messages are forwarded based on the node’s remaining battery, delivery predictability, and type of nodes. The performance of the proposed protocol is compared with that of probabilistic routing protocol using history of encounters and transitivity and probabilistic routing protocol using history of encounters and transitivity with periodic sleep in detail, from the aspects of delivery ratio, overhead ratio, delivery latency, and ratio of alive nodes. Simulation results show that the proposed protocol has better delivery probability, overhead ratio, and ratio of alive nodes, in most of the considered parameter settings, in spite of a small increase in delivery latency.

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