I need to build a small application to detect a ftp server's operating system and also it's server. Until now, I can only detect a web server's server but not the operating system (and not a ftp server :( ). Can anyone help me out?

Prasad Krishnamorthy

You have to check for port 21 to see whether a FTP server exists on a host. You can connect to that port and then use the 'SYST' command. For more details check out RFC 959