Having completed experimental work on this activity we now proceed to apply the lessons learned, and an improved version of the Hierarchical Storage Interface (hsi) software, to production transfers between the sites. The activities include removal of FDDI chokes at both sites, modifications to ftp at both ends and implementation of the improved hsi software.

(October 2000) Changes to production system parameters at both sites have been made. Transfer rates from ORNL to NERSC have improved from roughly 250 kilobytes/second to 1.8 megabytes per second. Rates from NERSC to ORNL are higher, up to 6 megabytes per second, and that asymmetry is now the target of additional testing. (November 2000) Two bugs in the IBM TCP stack have been identified and further evidence of packets being dropped has been gathered. The piece of equipment dropping packets has not been identified yet.

(July 2001) Both Probe sites are now on ESnet III with OC-12 connectivity. Performance has been fair from NERSC to ORNL but poor in the other direction. Recent replacement of the ORNL router with a Juniper router shows initial signs of better operation.

(November 2001) Using the new HPSS-HPSS version of hsi we achieve sustained bandwidths up to 12 megabytes/second.

Although we expect to give continued attention to this activity, we consider this particular project complete.

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