Port 21

FTP

FTP, running at TCP port 21, is one of the oldest protocols on the net. FSP (UDP) FSP (File Service Protocol) is an FTP-like UDP-based file transfer service.

FSP


 * Hardening the FTP service-How to configure your FTP service in order to avoid hacks.
 * Exploiting an FTP service-How hackers/crackers break into FTP services.
 * Trojan: DarkFTP