I was having a problem similar to this.  At least with certain web/ftp 
sites.  For instance I tried to download the Helix desktop about a hundred 
times and the connection would die within a couple minutes every 
time.  Windows downloads worked fine connected to the same modem pool at my 
ISP.  Then recently my ISP (Bitstream) switched me to a new modem pool and 
now my Linux downloads have stopped dying.

I would suggest trying a different ISP (like realtime.com which is 
supportive of Linux) or checking if your ISP can switch you to a new modem 
pool.

Brady

>Hiya,
>
>I have Debian Linux installed on my computer and an external modem.
>When I attempt to download anything (like the 2.4.0 kernel for example) my
>download constantly cuts out. By this I mean, a connection (ftp or http)
>starts, gets a download rate of about 4kb/sec, downloads for about 8
>seconds, translating to around 30kb of data, and then it just stops
>receiving.
>This is very frustrating.
>
>Now, I have tried 2 external modems, and get the same results. Also, I can
>download things over a Windoze partition on the same box without these
>problems.
>I am using an external US Robotics 56k Faxmodem.
>
>I don't see anything in the ppp logs. I also don't see anything in syslog.
>
>If I am doing something like openssh or telnet, the connection does not
>drop for a long time - perhaps because I am typing something in....but
>after seemingly random amount of time, I will suddenly not be able to
>converse with the other end. I end up having to drop my ppp connection and
>reconnect to start again.
>
>If it didn't work with Windoze either, I would guess it would be my ISP,
>but since it works, I am not sure what is going on here.
>
>____
>Mike
>
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