One of the key advances in this demonstration was Fast Data Transport (FDT; https://fast-data-transfer.github.io/), an open source Java application developed by the Caltech team in close collaboration with the Polytehnica Bucharest team. FDT runs on all major platforms and uses the NIO libraries to achieve stable disk reads and writes coordinated with smooth data flow across long-range networks.

The FDT application streams a large set of files across an open TCP socket, so that a large data set composed of thousands of files, as is typical in high-energy physics applications, can be sent or received at full speed, without the network transfer restarting between files. FDT works with Caltech’s MonALISA system to dynamically monitor the capability of the storage systems as well as the network path in real-time, and sends data out to the network at a moderated rate that achieves smooth data flow across long range networks.