Efficient Coded Caching with Limited Memory

Recently, coded caching techniques have received tremendous attention due to its significant gain in reducing the cost of delivery rate. However, this gain was only considered with the assumption of free placement phase. Motivated by our recent result of coded caching, we focus here on minimizing the overall rate of the caching network by capturing the transmission cost of the placement and delivery phases under limited storage memory at the end user. We model the dynamic nature of the network through a cost structure that allows for varying the network architecture and cost per transmission across the two phases of caching. The optimal caching decision for the worst case scenario with memory constraint is provided. Moreover, analysis of the delivery phase is proposed where trade-offs between system parameters, memory, and delivery rate are considered. Interestingly, we show that there are regions where the uncoded caching scheme outperforms the coded caching scheme. Finally, we provide numerical results to support and demonstrate our findings.