2023/12/22 by Rajlaxmi Pandey, Pandey, Rajlaxmi, Charul Rajput +3 · 1 citation
Computer Science · #Caching and Content Delivery #Cooperative Communication and Network Coding #FOS: Computer and information sciences #Information Theory (cs.IT) #Mobile Ad Hoc Networks
paper · doi:10.48550/arxiv.2312.15024
openalex publication_date 2023/12/22 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/29
We examine a two-layered hierarchical coded caching problem, a configuration addressed in existing research. This involves a server connected to K1 mirrors, each of which serves K2 users. The mirrors and the users are equipped with caches of size M1 and M2, respectively. We propose a hierarchical coded caching scheme with coded placements that outperforms existing schemes. To ensure a fair comparison, we introduce the notion of composite rate, defined as R = R1 + K1 R2, where R1 is the rate from the server to mirrors and R2 is the rate from mirrors to users. The composite rate has not been discussed before in the literature and is pertinent when mirrors transmit with different carrier frequencies. For the proposed scheme, we show a trade-off between the global memory M=K1M1+K1K2M2 of the system and the composite rate and compare with the existing schemes. Additionally, we conduct this comparative analysis by plotting R1 + R2 against global memory, which is particularly beneficial for systems wherein each mirror can utilize the same carrier frequency, given their significant spatial separation. Additionally, we propose an optimized scheme for the specific case of a single mirror, showing improved performance in this scenario.