Kurt Stammberger, Mocana
Implementing SSH on Devices: A guide for developers, with an introduction to Mocana’s NanoSSH embedded client and server
Earlier network-related programs, such as ftp (for file transfers), telnet (for remote logins), and rsh (for remote command execution) lack a basic security mechanism: encryption. Without encryption, users of such programs are vulnerable to eavesdropping, connection hijacking, and other attacks as they inadvertently expose all transmitted data, including passwords, to almost anyone who's interested. That's why SSH was developed.