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Which port number does IE use for FTP? 1

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wvmikep

Programmer
Feb 26, 2001
35
US
IE (and netscape) seem to use a "non-standard" port for FTP. I need to find out what port that is so our network idiots, I mean people ;) can know which port they need to free-up.

Thanks
 
wvmikep,

What makes you think they are using non-standard ports?
The well known port(s) for FTP are 20 for data and 211 for control. That is if you are using standard FTP. There is also PASV mode, Trivial FTP, Simple FTP. Be a little more specific and maybe one of us network idiots can help you out.

The Old Man
 
I can FTP using the command line or WS-FTP. However, when I go to any site that offers software for download (download.com, any software vendor that has an FTP:// link for their software, or Netscape's download page), I can't access the file for download.
 
wvmikep,

The difference is that your FTP clients use stanard FTP. THey use port 20 to transfer the data and port 21 to pass control info. Web browsers typically use passive (PASV) mode for FTP. In PASV mode, you connect to the FTP server and the browser issues the PASV comand which instructs the server to use passive mode. The server then picks a random port and advises the browser which port it is listening on. The transfer then occurs on that random port. Your firewall is blocking that random port.

Here is a description of how it works.

Tell your network guys to allow outgoing FTP connections on high-numbered ports.

The Old Man
 
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