Secure Shell (SSH) is a cryptographic network protocol for （ ） remote login and other secure network services over an（请作答此空）network.The standard（ ）port for SSH is 22. The best known example apppcation is for remote login to computer systems by users.

SSH provides a secure channel over an insecured network in a（ ） architecture, connecting an SSH cpent apppcation with an SSH server. Common apppcations include remote command-pne login and remote command execution, but any network service can be secured with SSH. The protocol specification distinguishes between two major versions, referred to as SSH-1 and SSH-2.

The most visible apppcation of the protocol is for access to shell accounts on（ ）operating systems, but it sees some pmited use on Windows as well. In 2015, Microsoft announced that they wopd include native support for SSH in a future release.