Do you have web hosting but dont know what active and passive FTP means??
File transfer via FTP in active or passive mode. Behind a firewall that uses NAT functions normally only passive mode. Why?
Protocol FTP is entirely based on TCP, UDP does not use FTP. FTP typically uses two ports, a control port and a data port. Data port is usually port “in” control port, ie port number – 1. The default is port 21 for control and 20 for data.
Active FTP
In active mode (active mode) connect client from a port (port 1024 or higher) to the server’s port 21. Then the client starts listening to another port and sends information to the server on which port to be used. The server then connects from port 20 (data port) to the port at the client as master and sends the requested data.
Passive FTP
In passvit mode (passive mode [PASV]) initerar client both control and data connection, which solves many problems with firewalls. (The firewall will allow traffic initiated from within the internal network – but block traffic initiated from outside.)
File transfer via FTP in active or passive mode. Behind a firewall that uses NAT functions normally only passive mode. Why?
Protocol FTP is entirely based on TCP, UDP does not use FTP. FTP typically uses two ports, a control port and a data port. Data port is usually port “in” control port, ie port number – 1. The default is port 21 for control and 20 for data.
Active FTP
In active mode (active mode) connect client from a port (port 1024 or higher) to the server’s port 21. Then the client starts listening to another port and sends information to the server on which port to be used. The server then connects from port 20 (data port) to the port at the client as master and sends the requested data.
Passive FTP
In passvit mode (passive mode [PASV]) initerar client both control and data connection, which solves many problems with firewalls. (The firewall will allow traffic initiated from within the internal network – but block traffic initiated from outside.)
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