In this work, a new model for federation data grid system called Sub-Grid-Federation was designed to
improve access latency by accessing data from the nearest possible sites. The strategy in optimising
data access was based on the process of searching into the area identified as ‘Network Core Area’
(NCA). The performance of access latency in Sub-Grid-Federation was tested based on the
mathematical proving and simulated using OptorSim simulator. Four case studies were carried out and
tested in Optimal Downloading Replication Strategy (ODRS) and the Sub-Grid-Federation. The results
show that Sub-Grid-Federation is 20% better in terms of access latency and 21% better in terms of
reducing remotes sites access compared to ODRS. The results indicate that the Sub-Grid-Federation
is a better alternative for the implementation of collaboration and data sharing in data grid system.