User-Driven Cache Replacement Strategy for Satellite-Terrestrial Networks Based on SDN

With the development of low-orbit satellite communication technology, caching on the satellites become feasible. However, due to the limited space on the satellites, content replacement has become a major factor affecting network performance. Aiming at the problems of the limitation of satellite network cache resources and poor content diversity, a user-driven satellite network cache replacement scheme was proposed to improve network performance. By analyzing content characteristics and user behaviors, a User-Driven Popularity Awareness Model (Udpam) is designed, and a replacement strategy is designed based on the content popularity and cache space of return path nodes. Simulation results show that compared with cache replacement strategies such as LCE and LRU, user-driven cache replacement strategy can provide higher direct cache hit rates and lower cache replacement rate.