Joint Pushing and Caching with a Finite Receiver Buffer: Optimal Policies and Throughput Analysis

TL;DR

This paper introduces a joint pushing and caching strategy that optimizes content delivery in wireless networks by considering buffer limitations and request delay information, significantly improving throughput.

Contribution

It proposes new offline and online policies for joint pushing and caching that adapt to different levels of request delay information, enhancing throughput in content-centric wireless networks.

Findings

Throughput increases with buffer size and pushing channel capacity.

Causal feedback significantly improves online policy performance.

Online policies outperform traditional caching methods.

Abstract

Pushing and caching hold the promise of significantly increasing the throughput of content-centric wireless networks. However, the throughput gain of these techniques is limited by the buffer size of the receiver. To overcome this, this paper presents a Joint Pushing and Caching (JPC) method that jointly determines the contents to be pushed to, and to be removed from, the receiver buffer in each timeslot. An offline and two online JPC policies are proposed respectively based on noncausal, statistical, and causal content Request Delay Information (RDI), which predicts a user's request time for certain content. It is shown that the effective throughput of JPC is increased with the receiver buffer size and the pushing channel capacity. Furthermore, the causal feedback of user requests is found to greatly enhance the performance of online JPC without inducing much signalling overhead in practice.