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Title: Age of Information Aware Cache Updating with File- and Age-Dependent Update Durations
We consider a system consisting of a library of time-varying files, a server that at all times observes the current version of all files, and a cache that at the beginning stores the current versions of all files but afterwards has to update these files from the server. Unlike previous works, the update duration is not constant but depends on the file and its Age of Information (AoI), i.e., of the time elapsed since it was last updated. The goal of this work is to design an update policy that minimizes the average AoI of all files with respect to a given popularity distribution. Actually a relaxed problem, close to the original optimization problem, is solved and a practical update policy is derived. The update policy relies on the file popularity and on the functions that characterize the update durations of the files depending on their AoI. Numerical simulations show a significant improvement of this new update policy compared to the so-called square-root policy that is optimal under file-independent and constant update durations.  more » « less
Award ID(s):
1717041
PAR ID:
10279420
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Proceedings of the International Symposium on Modeling and Optimization in Mobile Ad Hoc and Wireless Networks
ISSN:
2690-3334
Page Range / eLocation ID:
1-6
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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