Chapter 8: Cloud-RAN and Edge Caching

Learning Objectives

• Model the cloud-RAN architecture with edge nodes (ENs), fronthaul links, and caches
• Define the normalized delivery time (NDT) as a latency metric for cache-aided cloud-RAN
• Derive NDT bounds as a function of fronthaul capacity $C_F$ and cache size $M$
• Understand the cache-fronthaul tradeoff: extra cache reduces fronthaul demand
• Characterize the NDT surface $\Delta(M, C)$ and identify the Pareto frontier
• Connect the NDT framework to 5G/6G fog-RAN deployments