SITE Servername Authentication Command Sequence
The FTP Client uses the following command sequence to make a connection when you have configured Style to SITE servername in the Firewall section of the Security Properties dialog box.
OPEN <proxy_server>
USER <firewall_username>
PASS <firewall_password>
SITE <FTP_server>
USER <FTP_server_username>
PASS <FTP_server_password>
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