Application research of ant algorithm to replica selection in data grid

There are replication of data in data grid.But how to select a site which have the requested data to fufill the user's demand hasn't been solved up to the present.And a user should get the best services with the least cost.This problem is a multiobjective programming problem.The replica selection strategy is designed after making a deep research into the ant algorithm and investigating the key factors that influence the performance of replica selection greatly.This strategy is analyzed and implemented.Through using simulator, test results that this new ant algorithm can reduce data access latency, decrease bandwidth consumption and distribute storage site load, improve data access speed.