Difference Between FTP Active Mode FTP Passive Mode in 4 Points

Active Mode

Passive Mode

1)client initiates a random local port (N) Start listening Port N+1 Port should be greater than or equal to 1024 2)Client send PORT command send with Port N+1 Command to server.(these command tell the server to connect Active mode) 3)server will immediately connect to data port specified by the client from it local port 20. NOTE 1)Server initiate the Data connection 2)use the PORT Command.

1)client initiates a random local port (N) Start listening Port N+1 Port should be greater than or equal to 1024 1.1)First port connect to port 21 of server, 2)Client use the PASV command(these command tell the server to enter passive mode) 3)server replies to the Listening port N+1. 4)Client initiates data connection to transfer the data from (n+1) to the server. 1)client Initiate data connection 2)use the PASV command.