What is the difference between Active and Passive FTP session modes?
A. The File Transfer Protocol (FTP) has multiple modes of operation that can affect its operation and, as a result, the security of your network. These modes of operation determine whether the FTP server or FTP client initiates the TCP connections that send information from the server to the client. The FTP protocol supports two modes of operation: •Active Mode •Passive Mode Active Mode In Active FTP, the client opens a control connection on port 21 to the server. Whenever the client requests data from the server, the server opens a TCP session on port 20. The Active mode of operation is less secure than the Passive mode. This mode of operation complicates the construction of firewalls, because the firewall must anticipate the connection from the FTP server back to the client program. The steps in the Active mode are: 1. The client opens a control channel (port 21) to the server and informs the server which port number it should respond to. This port number is a randomly determined por
