ABSTRACT
Secure shell (SSH) is a cryptographic network protocol for secure data communication, remote command-line login, remote command execution, and other secure network services between two networked computers. It connects, via a secure channel over an insecure network, a server and a client running SSH server and SSH client programs, respectively. Remote login to Linux compute server needs to use an SSH. Here, we use PuTTY as an SSH client example. PuTTY was developed originally by Simon Tatham for the Windows platform. PuTTY is an open-source soware that is available with source code and is developed and supported by a group of volunteers. PuTTY can be freely and easily downloaded from the site (https://www.putty.org/) and installed by following the online instructions. Figure 1.1a displays the starting portal of a PuTTY SSH. When you input an IP address under Host Name (or IP address) such as 10.250.20.231, select Protocol SSH, and then click Open; a login screen will appear. Aer successful login, you are at the input prompt $ as shown in Figure 1.1b and the shell is ready to receive proper command or execute a script.
