Efficient 3-D scene prefetching from learning user access patterns

Rendering large-scale 3-D scenes on a thin client is attracting increasing attention with the development of the mobile Internet. Efficient scene prefetching to provide timely data with a limited cache is one of the most critical issues for remote 3-D data scheduling in networked virtual environment applications. Existing prefetching schemes predict the future positions of each individual user based on user traces. In this paper, we investigate scene content sequences accessed by various users instead of user viewpoint traces and propose a user access pattern-based 3-D scene prefetching scheme. We make a relationship graph-based clustering to partition history user access sequences into several clusters and choose representative sequences from among these clusters as user access patterns. Then, these user access patterns are prioritized by their popularity and users' personal preference. Based on these access patterns, the proposed prefetching scheme predicts the scene contents that will most likely be visited in the future and delivers them to the client in advance. The experiment results demonstrate that our user access pattern-based prefetching approach achieves a high hit ratio and outperforms the prevailing prefetching schemes in terms of access latency and cache capacity.