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Example of Grid
file transfer: a grid scheduler determines that a copy of a given file
needs to be copied to site A before a job can be run. Several copies of this
file are ina Grid Replica Catalogue so there is a choice of where to copy the
file from. The Grid Scheduler needs to determine the optimal method to create
this new file copy, and to estimate how long this file creation will take. To
make this selection the scheduler must have determined what is the best
source (or sources) to copy the data from. Selecting the best source to copy
the data from requires a prediction of future end-to-end path characteristics
between the destination and each possible source. Accurate prediction of the
performance obtainable from each source requires measurement of available
bandwidth (both end-to-end and hop-by-hop), latency, loss, and other
characteristics important to transfer performance. Profile for Network
Performance Measurements for Grids, GGF NMWG group.
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