Performance Profits of Tile Pre-fetching in Multi-level Abstracted Web Geographical Information Systems

초록

An effective probability-based tile pre-fetching algorithm is able to reduce the response time by pre-transferring tiles that are likely to be used in Web geographical information systems (Web GISs). But, up to our knowledge, no experimental study showing the performance profits of probability-based tile pre-fetching in Web GISs in which mulit-level abstracted map data is managed to support user's zooming commands has not been announced yet. In this paper, an extended version for multi-level abstracted Web GISs of a previous probabilit-based tile pre-fetching algorithm is briefly described. Then, we identify the performance profits of the proposed probability -based tile pre-fetching algorithm by simulation experiments. Through the experimental results, the response time for user requests is improved between 1.8% and 21.6%. Consequently, in Web GISs with multi-level abstracted data, probability-based tile pre-fetching algorithm can reduce the response time for user request substantially.