SSH (otherwise known as secure shell) is a network protocol that's designed to enable the exchange of data through a protected avenue between two linked gadgets or machines.It's the next generation of remote shells, replacing old standards such as Telnet (a protocol that delivers information, notably passwords, in unencrypted plaintext, which leaves it exposed to interception during data transmissions), and it's used mostly on Unix- and Linux-based operating systems to handle shell accounts. The encryption approach of SSH offers data integrity and assured confidentiality over the Internet and other notoriously insecure computer networks.
The client-server-based SSH also employs a public key methodology to confirm that the remote machine you're exchanging data with is secure and vice-versa. Moreover, its cryptography approach works on a case-to-case basis, which allows for extra versatility regardless of the circumstances. The ever-adaptable network protocol is usually deployed during command executions and logins into a distant, physically inaccessible computer. Furthermore, it also supports file transferring via the associated SCP or SFTP protocols, forwarding X11 connections and TCP ports, and tunneling as well.
What's more, the standard TCP port 22 has been specifically allocated for the sake of linking to SSH servers, so compatibility isn't a problem for this standard either. The SSH client application is often utilized for establishing connections to an SSH daemon that receives remote links. Both of them are typically available on most of the latest operating systems out there, which includes Microsoft Windows, OpenVMS, Solaris, FreeBSD, Linux, and Mac OS X. Open source, freeware, and propriety variants of this protocol are available in varying levels of completeness and complexity.
The number of applications and platforms you can use the SSH standard on are numerous, which proves this modern security measure's ubiquitous accessibility. Nonetheless, several programs may need features that are only suitable or obtainable with specific SSH servers or clients, so it's always best to consult your software or platform provider about SSH compatibility. For instance, even though using SSH to employ a VPN is viable, it could only be done with client implementation and the OpenSSH server present.