Mac® Security Bible

11.1. Transferring Files

If you're copying files between computers on your local network, you can be reasonably confident that you're safe from eavesdropping — at least if you use a wired Ethernet network or a Wi-Fi network protected with WPA or 802.1x encryption, along with a NAT gateway of some kind — and that's true regardless of which protocol you use. However, if you want to transfer files to or from computers outside your local network, you should think more carefully about security because merely having a username and password isn't necessarily enough to keep your data (and your credentials) safe.

In this section, I discuss several of the protocols used for transferring files to and from remote computers. Then, I show how to use these protocols in the Finder (to the extent the Finder supports remote transfers) and other popular applications.

11.1.1. FTP, SCP, SFTP, and FTPS

The first thing many people think when they hear FTP is something along the lines of, "Oh, yeah, that's how you download software from websites." Even though it's less often the case than it once was, it's true that many websites that distribute software still store those files on a server separate from the web server where the HTML files reside; if you click a link that starts with ftp://, you're downloading a file from an FTP server. FTP, or File Transfer Protocol, was in existence long before the web, and because it was an established, reliable way of transferring files, a lot of people stuck with ...