Just a thought. Say a download going at 1 gigaBIT was being saved to a disk thats writes as a speed of say 50 megaBYTEs. Would software throttle it? Would it then get buffered into memory? If so, what happens when you out of memory?
TCP flow control.
This negotiates and manages the speed at which data is transmitted so that the receiver doesnt take in more data than it can process.
Just guessing here so don't look at this as "The Answer"
LOL...I had to answer the phone while typing....and Eden beat me to hitting reply. ;)