Abstract:
To satisfy the explosive growth of mobile data, caching at wireless edge has attracted significant research efforts for the next generation of the wireless communication. To which extent the traffic model matches the real traffic largely affects the accuracy of performance evaluation on wireless local caching. However, the content request model adopted in almost all existing studies does not take the content popularity dynamics into consideration. Although there were several works that considered dynamic popularity, only reactive caching policy was evaluated. Yet proactive caching is important for wireless caching networks. This paper analyzes the impact of dynamic popularity on the cache hit ratio and average network throughput with proactive and reactive caching policies, based on Shot Noise Model (SNM) that can capture the content popularity dynamics, and Independent Reference Model (IRM) that is widely used in the literatures. Simulation results show that whether or not using SNM has large impact on the evaluated throughput of wireless networks, especially when the interference level is low. Moreover, the conclusions obtained from reactive caching policies are not applicable to proactive caching policies.