FTP has been called the misbehaving child of networking, and I'm being kind. 
While other protocols play nicely on a network, not grabbing all the bandwidth 
they can and refusing to throttle down when needed, FTP generally does the 
opposite. FTP will try to commandeer all the bandwidth your infrastructure 
allows, and won't let go once it has it.

I'm sure modern FTP servers are better behaved than their cave-man-days 
predecessors, but the protocol itself is still what it is.

If you have a router or switch with built in QOS, you may be able to do it 
there. Barring that you may want to use HTTP file transfers instead.

Bob S


On Sep 21, 2015, at 14:33 , Gregory Lypny 
<gregory.ly...@videotron.ca<mailto:gregory.ly...@videotron.ca>> wrote:

Hello everyone,

I posted about this a while back but am still having trouble.

I need to download thousands of files from the Security and Exchange 
Commission's website. Access is through anonymous FTP with "anonymous" as the 
username and my email address as the password. I've been using Put in a Repeat 
With loop as

repeat with each line remoteFilePath in listOfFilePaths
— set new localFileName is set before the download request is made
   put url ("ftp://anonymous:myemailaddr...@ftp.sec.gov/"; & remoteFilePath) 
into url ("file:/" & exportFolderPath & "/" & localFileName )
end repeat

but my script dies (the stack is lifeless and unresponsive) after a few dozen, 
and sometimes a few hundred downloads. I used similar scripts in Mathematica 
and confirmed that the problem is session-timed-out and 
cannot-connect-to-server types of errors. The SEC's webmaster tells me, "There 
is no load/rate limiting on FTP, but if you are running a fast process, it is 
possible you are temporarily overwhelming the server." So, I'm thinking that I 
need to throttle my requests, and maybe should be using libURLDownloadToFile to 
check the status of the current file being downloaded and not request another 
file until the current download is complete. I also wonder whether I should be 
connecting to the FTP site only once with the username and password, loop my 
requests, and then close the connection. Not sure how to do either of these and 
would greatly appreciate any suggestions or tips.

Gregory

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