SSH is a remote login login application like telnet, rsh, and rlogin, which is much more secure. Developed first by the OpenBSD project and then the release version p (port) is managed by the team ported to other operating systems, including the Linux operating system. The main function of this application is to access the machine remotely. The form of remote access that can be had is the mode mode and the graphical mode / X configuration area allows. Scp which is a member of the ssh family is a secure rcp replacement app, the other family is sftp which can be used instead of ftp.
The OpenSSH server component, sshd, listens continuously during the client connection from one of the client tools. When a connection request occurs, sshd establishes the correct connection depending on the type of tool connecting the client. For example, if a remote computer connects with a client ssh application, the OpenSSH server creates a remote control session after authentication. If the remote user connects to the OpenSSH server with scp, the OpenSSH server daemon initiates a secure copy of the files between the server and the client after authentication. OpenSSH can use authentication methods, including plain passwords, public keys, and Kerberos tickets.
Remote login service is a required service to internet users. To access (login) to a terminal (remote host) in the internet network environment. By utilizing remote login, an internet user can operate a host remotely without having to physically.From there he can perform maintenance (maintenance), run a program or even install a new program on the remote host. The commonly used protocol for remote login purposes is Telnet.