Take the 2-minute tour ×
Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

I would like to know exactly what the difference is between the following protocols: FTPS, SFTP, and SCP. For instance Unix has an scp tool, FileZilla offers FTP and SFTP, whereas JetBrains PhpStorm offers distinct SFTP and FTPS protocols.

Thanks for the clarification.

share|improve this question

2 Answers 2

up vote 17 down vote accepted

FTPS is FTP using the SSL protocol for encryption. This is different from the SCP/SFTP family of protocols which use SSH as their transport tunnel. You will usually use the same client programs for scp and sftp (WinSCP for instance; SFTP is an upgraded version of SCP), whereas you usually use a web browser or web Download manager (like filezilla) for FTPS. FTPS is web-based, whereas SFTP is based on secure shell protocols pioneered on *NIX systems.

This article describes the differences nicely: http://www.codeguru.com/csharp/.net/net_general/internet/article.php/c14329/FTPS-vs-SFTP-What-to-Choose.htm

Edit: To expound as requested:

FTP is a core Internet protocol that goes back to 1971 (with a number of updates over the years). FTP is primarily focused on content distribution and the SSL just provides security from eavesdropping and illicit modification. Most browsers do require an external plugin, for a few reasons but the most prevalent being that almost no one uses FTPS anymore, and last time it was popular, web browsers were almost exclusively HTTP only, and everyone used a separate FTP client. At the time FTP was most popular and FTPS made the most sense, HTTP was not capable of handling file downloads well; not until HTTP\1.1 was published in 1997 (and updated in 1999). FTPS use has been waning for a very long time now, and is usually used in niche circumstances these days.

The SSH family is a set of protocols focused on server administration and remote access to the servers processing capability, rather than simple content distribution. it would allow privledged users of a system to connect to a shell to perform work on the server itself, and many file management tasks related to that work involve transferring files between the localhost and the server, which is why SCP and eventually SFTP were developed. Imagine you need to install an update to your apache instance on a remote server. you ssh in, use scp\sftp to upload the update package, and then execute it to install. Quite a different work flow than you can achieve with FTPS.

I hope that helps clarify.

share|improve this answer
1  
The first two and half sentences in your answer are good but could you please show me a browser which supports FTPS (without a plug-in)? What do you mean by the statement "FTPS is web based"? What does it have in common with the web? Theoretically it could be used as a "transfer" protocol besides the common HTTP/HTTPS but you can find many protocols which could be used for this purpose. –  pabouk Nov 20 '13 at 10:50
    
I have opened a question on Meta Stack Overflow because this answer was included into the review audit pool. –  pabouk Nov 20 '13 at 12:16
1  
I had to downvote your answer mainly because it is certainly not a good answer for the review audits. The statement "FTPS is web-based" is very misleading even with the explanation you added. I still do not understand what did you mean by the statement. Maybe that FTP links were (are) often being used in web hypertext documents (while SCP and SFTP not)? –  pabouk Nov 21 '13 at 3:43
    
I have no idea what a review audit is, but whatever you think you need to do. –  Frank Thomas Nov 21 '13 at 3:57
    
Here is an explanation: What are review tests (audits) and how do they work? The problem is that just clicking on "add comment" causes the audit to fail. –  pabouk Nov 21 '13 at 4:07

SCP is the file transfer tool from SSH. It requires SSH on both client and server. It is not interactive.

SFTP is another file transfer tool that can be used with SSH (so it again may require SSH on both client and server) or with any other compatible secure connection tool, since it is intended to be independent of SSH. It is interactive like the old plain FTP. Note that it is not FTP over SSH, but a new protocol.

FTPS is plain old FTP over SSL.

share|improve this answer

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.