Unix telnet will attempt to detect or guess whether the service it is talking to is a real Telnet service or not PuTTY prefers to be told for certain.
Really there is no actual protocol at all the bytes sent down the connection are exactly the ones you type, and the bytes shown on the screen are exactly the ones sent by the server. For example, telnet 25 might enable you to talk directly to the SMTP service running on a mail server.Īlthough the Unix telnet program provides this functionality, the protocol being used is not really Telnet. PuTTY is open source software that is available with source code and is developed and supported by a group of volunteers. PuTTY is a popular client-side program available for Windows, macOS, Unix, and Unix-like systems such as Linux that is designed for use with the SSH. On Unix machines, you can do this using the system's telnet command to connect to the right port number. PuTTY is an SSH and telnet client, developed originally by Simon Tatham for the Windows platform.
Sometimes it can be useful to connect directly to one of these services and speak the protocol ‘by hand’, by typing protocol commands and watching the responses.
