Optimal caching placement for wireless femto-caching network

TL;DR

This paper develops a low-complexity greedy algorithm to determine optimal caching placement in wireless femto-caching networks, balancing file and channel diversity to minimize bit error rate under wireless fading.

Contribution

It introduces a novel greedy algorithm leveraging properties of optimal placement, and derives closed-form solutions under certain conditions, advancing caching strategies in wireless networks.

Findings

Optimal caching placement balances file and channel diversity gains.

The proposed algorithm reduces search space significantly.

Closed-form solutions are derived for specific scenarios.

Abstract

This paper investigates optimal caching placement for wireless femto-caching network. The average bit error rate (BER) is formulated as a function of caching placement under wireless fading. To minimize the average BER, we propose a greedy algorithm finding optimal caching placement with low computational complexity. Exploiting the property of the optimal caching placement which we derive, the proposed algorithm can be performed over considerably reduced search space. Contrary to the optimal caching placement without consideration of wireless fading aspects, we reveal that optimal caching placement can be reached by balancing a tradeoff between two different gains: file diversity gain and channel diversity gain. Moreover, we also identify the conditions that the optimal placement can be found without running the proposed greedy algorithm and derive the corresponding optimal caching placement in closed form.