Cost-Aware Joint Caching and Forwarding in Networks with Heterogeneous Cache Resources

Caching is vital for high-throughput networks in data-intensive applications. Dynamic random-access memory (DRAM), often used for caching due to its high data transfer rate, faces limitations in capacity and cost, hindering scalability needed to meet growing demand. Evolving flash storage can augment DRAM, but necessitates caching techniques adapted to its charac-teristics for optimal network performance. This paper models the cache as a set of storage blocks with varying rate parameters and utilization costs. Utilizing a framework that enables joint caching and forwarding, we introduce an optimization technique based on the drift-plus-penalty method. Our approach minimizes the drift-plus-penalty expression in a virtual control plane and offers a throughput-cache utilization cost trade-off. We implement a corresponding practical policy in the data plane. Simulations demonstrate the superior performance of our approach in total delay and cache utilization costs.