HELP: Speeds drop from normal to <.5k!

I'm connecting to a UNIX server at Columbia U. and getting an average download speed of 200k/s. Pretty normal for this guy's server. All of a sudden and without error the speed drops to under 1 kb/s until a timeout occurs. Loging back on the connection speed is still below 1kb/s. Intermitantly I can get normal speeds back, but it always drops again. I've tried passive and active modes with no resolve. Any ideas? The server owner has others pulling data with no issues at all.

I have a 1500 cable modem connection. Thanks.

well. for sure this have nothing to do with smartftp.
check your connetion, your settings, or even check if Columbia u dont have some kind of cap or something.

carlos