Measuring a FASP file transfer
Inspired by the (U. S.) National Center for Biotechnology Information’s ‘Aspera Transfer Guide’ [NCBI 2014]
Downloaded and installed Aspera Connect software from: http://downloads.asperasoft.com/connect2/ Links to an external site.
Transferred a 1Gbyte test file – while collecting data using:
tcpdump –I eth0 –w /tmp/xxxxxxxFast adaptive secure protocol (FASP) is a file transfer protocol designed by Aspera (now part of IBM) for transferring very large files using UDP as the underlying protocol and using its own algorithm for pacing the sending of these UDP packets. Unlike traditional TCP congestion control algorithms, it adjusts its sending rate based upon measurements of the arrival times of packets rather than packet loss. However, as the protocol is proprietary we do not know exactly how it works. In the following pages, we will look at measurements of the traffic between a client and server using this protocol.
[NCBI 2014] National Center for Biotechnology Information, ‘Aspera Transfer Guide’, National Center for Biotechnology Information, U.S. National Library of Medicine, 16-Apr-2014. [Online]. Available: http://www.ncbi.nlm.nih.gov/books/NBK242625/. [Accessed: 18-Aug-2015]
Transcript
Now, I was inspired by the National Center for Biotechnology Information's "Aspera Transfer Guide", because a master's thesis student who was using this Aspera protocol for transferring files. This protocol designed to be able to rapidly transfer very large files. So I said, "okay, let's do an experiment to see how fast it does transfers" and "can I understand what's going on in this protocol even though the protocol is proprietary". So I set up the data collection using a one-gigabyte test file, and I use tcpdump to capture the traffic as described here on interface 0, and I wrote it to a temporary file.