Performance evaluation for caching-based content distribution in backhaul-limited small cell networks

Abstract

Distributed caching at the edge can reduce the backhaul resource consumption, which is considered as a major way to improve network capacity in dense small cell networks. In this paper, we consider the caching-based content distribution in dense small cell networks. In such a content distribution system, the most critical metric is the user request blocking probability. A user's request will be rejected if the content is not cached at the associated SBS and there is no backhaul resource available at the SBS. In this paper, we develop an analytic model to derive the blocking probability as the function of cache capacity, available backhaul resource, and request arrival rates. Based on the analysis, the optimal resource configuration is determined to minimize the blocking probability. Extensive simulations are conducted to validate our analysis.