On Coded Caching Systems with Decentralized Linear Coding Placement

Abstract: Coded caching is a technique that leverages locally cached contents at the end users to reduce the network's peak-time communication load. Coded caching has been shown to achieve significant performance gains with a centralized placement orchestrated by the server and is thus considered a promising technique to boost performance in future networks by effectively trading off bandwidth for storage. To tackle issues caused by the synchronized placement, previous works focused on decentralized placement and found the exact worst-case load with uncoded placement. In this paper, we focus on a decentralized coded caching system with random linear coding placement, and investigate the fundamental limits of a linear coding placement where each user independently and uniformly caches random linear coding symbols of a single file. We propose achievable and converse bounds on the worst-case load, which are shown to meet under certain conditions.