SFTP is not FTP

Today I encountered another confused person who thought that to provide SFTP service, he had to install an FTP server.

I'm writing this post so that I can point people to it next time I encounter this misconception.

Yes, SFTP stands for Secure File Transfer Program and FTP stands for File Transfer Protocol but there the similarity ends. SFTP is run over a ssh connection, which normally uses the single service port 22. FTP is a different protocol using two ports, normally 20 and 21 for data and command (I will not go into the complexity of active and passive modes here). They are not related. The Wikipedia entry for FTP explains it succinctly. SFTP servers are different from FTP servers. Although there are clients that are capable of connecting to both types of servers, for example, Filezilla.

If you can ssh to a server, you can probably sftp also. I qualified that claim with "probably" because the sftp functionality has to be enabled and allowed to users.

SFTP is much much preferred over FTP due to encryption of the stream.

To complicate things there is a variant of FTP called FTPS which uses TLS to encrypt the stream.