When I try and open the ftp using Chrome I get:
Is this what you see?
When I click on average_rtt-100-by-node/ then in Chrome I get
Scroll down to some recent data, e.g. average_rtt-100-by-node-2014-09-10.txt.gz. Click on it and in Chrome
The file appears at the bottom left
Drag this file to a more permanent place (e.g. your desktop). Then you have to unzip it. How you do that depends on your OS. I would do it in Unix. So I copy it to a Unix host and use gunzip. On windows I copy it to the desktop and the use WinRAR (you may need to download) to unzip and look at.
There is a copy of the file here.