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arXiv · 1608.08622

The Age of Information: Real-Time Status Updating by Multiple Sources

Roy D. Yates·Sanjit K. Kaul
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Abstract

We examine multiple independent sources providing status updates to a monitor through simple queues. We formulate an Age of Information (AoI) timeliness metric and derive a general result for the AoI that is applicable to a wide variety of multiple source service systems. For first-come first-served and two types of last-come first-served systems with Poisson arrivals and exponential service times, we find the region of feasible average status ages for multiple updating sources. We then use these results to characterize how a service facility can be shared among multiple updating sources. A new simplified technique for evaluating the AoI in finite-state continuous-time queueing systems is also derived. Based on stochastic hybrid systems, this method makes AoI evaluation to be comparable in complexity to finding the stationary distribution of a finite-state Markov chain.

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Roy D. Yates, Sanjit K. Kaul. 2016-08-30. The Age of Information: Real-Time Status Updating by Multiple Sources. https://arxiv.org/abs/1608.08622

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