Proceedings ArticleDOI
Two Freshness Metrics for Local Cache Refresh
Jing Zhong,Roy D. Yates,Emina Soljanin +2 more
- pp 1924-1928
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TLDR
The AoI optimal policy is derived, which depends only on the square root of the source popularity, and an AoS near-optimal rate allocation policy is proposed that is proportional to the cube root of both the source update rate and the sources popularity.Abstract:
We consider a cache refresh system where a local server is connected to multiple remote sources and maintains local copies of the data items at the sources. The data at each source is updated randomly and independently without notifying the local server, while the local server refreshes the corresponding cached data periodically. The freshness of the local cache is measured by two different freshness metrics, age of synchronization (AoS) and age of information (AoI). We address the following problem: given a constrained total refresh rate, how does the local server allocate the refresh rate for each source to maintain overall data freshness? We derive the AoI optimal policy which depends only on the square root of the source popularity. For a large refresh rate, we propose an AoS near-optimal rate allocation policy that is proportional to the cube root of both the source update rate and the source popularity. For small refresh rates, we also prove that the square root law with respect to the popularity minimizes both AoS and AoI.read more
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Age of Information: A New Metric for Information Freshness
TL;DR: Abstract Information usually has the highest value when it is fresh, and for example, real-time knowledge about the location, orientation, and speed of motor vehicles is imperative in autonomous vehicles.
Journal ArticleDOI
Age of information performance of multiaccess strategies with packet management
TL;DR: The age of information (AoI) performance of the system under scheduled and random access is investigated and analysis of the AoI with and without packet management at the transmission queue of the source nodes is presented.
Journal ArticleDOI
The Age of Incorrect Information: A New Performance Metric for Status Updates
TL;DR: In this paper, a new performance metric called the Age of Incorrect Information (AoII) was introduced to deal with the shortcomings of both the AoI and the conventional error penalty functions.
Posted Content
The Age of Incorrect Information: A New Performance Metric for Status Updates
TL;DR: This paper introduces a new performance metric in the framework of status updates that is referred to as the Age of Incorrect Information (AoII), and provides a rigorous mathematical proof to showcase that a mixture of two Lagrange policies is optimal for the CMDP in question.
Posted Content
On The Optimality of The Whittle's Index Policy For Minimizing The Age of Information
TL;DR: The Whittle’s index policy has analytically provable optimality in the many-users regime for the AoI minimization problem and rigorous results on its asymptotic optimality are provided.
References
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Journal ArticleDOI
Update or Wait: How to Keep Your Data Fresh
TL;DR: In this paper, the authors study how to optimally manage the freshness of information updates sent from a source node to a destination via a channel and develop efficient algorithms to find the optimal update policy among all causal policies and establish sufficient and necessary conditions for the optimality of the zero-wait policy.
Proceedings ArticleDOI
Real-time status updating: Multiple sources
Roy D. Yates,Sanjit K. Kaul +1 more
TL;DR: A status-age timeliness metric is formulated and the region of feasible average status ages for a pair of updating sources is found and the existence of an optimal rate at which a source should generate its updates is shown.
Journal ArticleDOI
Effective page refresh policies for Web crawlers
Junghoo Cho,Hector Garcia-Molina +1 more
TL;DR: This article proposes various refresh policies and studies their effectiveness, and shows that a Poisson process is a good model to describe the changes of Web pages and improves the "freshness" of data very significantly.
Proceedings ArticleDOI
Optimizing age-of-information in a multi-class queueing system
Longbo Huang,Eytan Modiano +1 more
TL;DR: This paper derives the exact peak age-of-Information (PAoI) profile of the system, which measures the “freshness” of the status information, and seeks to optimize the age of information, by formulating the problem using quasiconvex optimization, and obtaining structural properties of the optimal solution.
Proceedings ArticleDOI
Age of information: The gamma awakening
Elie Najm,Rajai Nasser +1 more
TL;DR: This work considers a scenario where a monitor is interested in being up to date with respect to the status of some system which is not directly accessible to this monitor, and considers two packet management schemes: LCFS with preemption and LCFS without preemption.