This work studies the K-user broadcast channel with Λ caches, when the association between users and caches is random, i.e., for the scenario where each user can appear within the coverage area of – and subsequently is assisted by – a specific cache based on a given probability distribution. Caches are subject to a cumulative memory constraint that is equal to t times the size of the library. We provide a scheme that consists of three phases: the storage allocation phase, the content placement phase, and the delivery phase, and show that an optimized storage allocation across the caches together with a modified uncoded cache placement and delivery strategy alleviates the adverse effect of cache-load imbalance by significantly reducing the multiplicative performance deterioration due to randomness. In a nutshell, our work provides a scheme that manages to substantially mitigate the impact of cache-load imbalance in stochastic networks, as well as – compared to the best known state-of-the-art – the well-known subpacketization bottleneck by showing its applicability in deterministic settings for which it achieves the same delivery time – which was proven to be close to optimal for bounded values of t – with an exponential reduction in the subpacketization.
Stochastic coded caching with optimized shared-cache sizes and reduced subpacketization
ICC 2022, IEEE 1st International Workshop on Semantic Communications, 16-20 May 2022, Seoul, South Korea (Virtual Event)
Systèmes de Communication
© 2022 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.
PERMALINK : https://www.eurecom.fr/publication/6776