FTP proxies are IP addresses that leaves port 21 (FTP) and port 22 (SSH) open. In most cases, they are used to access a web server because web developers and IT technicians often require static IP addresses that allow SSH & FTP access. In computing terms, SSH File Transfer Protocol, also known as Secure File Transfer Protocol is essentially dubbed as a network protocol. This protocol provides functionalities like file management, file transfer, and file access over any reliable data stream.
Both SSH and FTP are network protocols that operate over the IP/TCP layer. It is used to facilitate communication between devices connected to the same network.
Shell Accounts and Shells
To better understand the purposes of SSH, it is best to learn some of the basic terminologies associated with it. For starters, the shell (computer software) allows users to establish direct connection with the kernel, which comprises the very center of an operating system. The interface of the shell can be in command-line, graphical, or a combination of both.
A Shell account is generally a personal account, which the user may use to gain access to the shell of another computer. These are mostly provided by ISPs (Internet Service Providers) and are used for email accounts, newsgroups, and file storage. Commands are often delivered to remote computers through shell accounts.
Secure Shell Protocol
Communication is established between web browsers and websites with an HTTP Protocol. Data exchange through a shell account is done over a certain protocol; this is also the job of SSH proxies. Next, the public key encryption was developed to replace unsecure protocols like Telnet. Accessing shell accounts is now done by dominant internet protocols like SSH-1 and the SSH-2. All major operating systems, including Mac, Linux and Windows make use of OpenSSH.
SFTP and FTP
SSH does not, by default, host VPN applications and File transfer. They run on SFTP or the SSH File Transfer Protocol. You should note that SSH that supports FTP protocol is not SFTP. It is a completely separate file transfer protocol which was developed as an SSH-2 extension. Transferring files is always preferable on SFTP.
While there is no official note to it, SFTP is seen by many as a secured variant of FTP. As the latter is used in plain-text data transmission, private and sensitive data may become visible through the packets that get transmitted back and forth. This information may include usernames and passwords! SFTP, on the other hand, makes use of public key security like an SSH-2 extension. This prevents any unauthorized interceptions from happening as there is data encryption at the time of transmission. Several popular FTP Suites still make use of SFTP, even though it is often used without the SSH functionality.