An improved caching scheme for nonuniform demands and its optimal allocation
Haoshuai Ding, Lawrence Ong · 2017
In content delivery networks, as more contents are being generated and the size of contents is increasing, caching has been identified as a solution to cope with congestion in communication links. The idea is to prepopulate users' cache with parts of files in off-peak time to ease the peak-time delivery traffic. In this paper, we consider nonuniform demands, where different files have different probability of being requested. We consider networks with a server connected to multiple users through a shared link. The goal is to design cache placement schemes that minimize the transmission rate from the server during peak-time content delivery. In this paper, we analytically prove that a caching scheme proposed by Zhang et al., which they showed to achieve within a constant multiplicative and additive gap from the optimal rate, is indeed optimal when there are only two users.