Good question. There are two methods of doing so:
I hope to eventually expand this into a section with screenshots and stuff, but right now I'm just trying to get the general skeleton done. Here's a quick rundown on how to do it:
Tell your ssh program to forward local port 21 to remote host:port yip.org:21.
The advantage of using port forwarding to transfer files is that your cracked webcam software from 1993 or your drag 'n drop commercial FTP software you paid good money for will work with this. The disadvantages are: 1) many ssh programs are buggy and will hold onto their forwarded ports after they are closed, forcing you to reboot before being able to use the forward again. Symptoms of this are usually connection attempts that hang, or "Connection refused" error messages. 2) Only the login info will be private - the files transferred can be seen by anyone watching the traffic. This is generally ok as long as you're uploading webpages or other non-sensitive information.
As a side note, yip.org also offers ftp-only accounts that can be restricted to a certain directory. If you simply must use unencrypted ftp, please contact us and we'll hook you up with one.
MacSFTP is an sftp client - you can download the beta here - .sit - but you may need the Carbon Library to use it. Or you could just get the Classic version. Liz at YIP has reported what sound like protocol errors when trying to use MacSFTP Carbon. Perhaps the Classic version might work, or might not.
New! MacOS X users can use Fugu, a graphical front-end for the commandline SFTP in the base system. Recommended by Phenethaine.
NiftyTelnet 1.1 revision 3 claims to support Secure Copy (scp) with lots of bugs fixed in the latest version. So far no documentation has been found on this, much less reports of whether it works or not.
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