Wikipedia
The Secure Shell Protocol (SSH) is a cryptographic network protocol for operating network services securely over an unsecured network Typical applications include remote command-line, login, and remote command execution, but any network service can be secured with SSH SSH provides a secure channel over an unsecured network by using a client–server architecture, connecting an SSH client application with an SSH server The protocol specification distinguishes between two major versions, referred to as SSH-1 and SSH-2 The standard TCP port for SSH is 22 SSH is generally used to access Unix-like operating systems, but it can also be used on Microsoft Windows
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