First, the PASV and PORT modes in the FTP connection:

PORT: it's actually another name for the Standard pattern, also known as the Active model. Active mode;

PASV: that's the abbreviation for Passive. Chinese is passive mode.

Two, what's the difference between the two?:

1, the difference is that, because PORT this way, you need to connect to the TCP 21 port, the server through its own TCP 20 to send data. And you need to set up a new connection to send the file. The PORT command contains some data that the client doesn't have, so there is a PASv;

2, and the PASV model certainly has the advantages of the PORT model and removes some of the PORT's drawbacks. The PASV operation means that when the server receives the PASV command, it automatically selects randomly from port 1024 through 5000, and uses the same port to transfer data without having to build a new connection.

Three, some FTP server does not support PASV mode, login to cancel PASV mode will do. The commonly used FTP download tools cancel the PASV schema as follows:

1, Cutftp: on the menu "file" > "site management" in the "> Site Manager window >" new site "> fill in the" domain name ">" Edit ">" conventional ">" PASV mode "before the hook removed.

2, FlashFXP: on the menu "site" > "site manager" > Site Manager window > "new site" > fill in the "domain name" > "option" > "use passive mode" before the "application" can be removed > google.

3, FileZilla: on the menu "site" > "site manager" > Site Manager window "> transfer settings" > "transmission mode" > choose "active" or "default".