RE: IP-conntrack / ftp

[Alexey Talikov]

how works active ftp
ftp ftp.somwhere.com
client________server
dyn1  -------> ftp
dyn1  <------- ftp
auth  <------- dyn2  authorization
auth  -------> dyn2  authorization
dyn3  -------> dyn4  ls command
dyn3  <------- dyn4  ls command
passive ftp 
client________server
dyn1  -------> ftp
dyn1  <------- ftp
auth  <------- dyn2  authorization
auth  -------> dyn2  authorization
dyn3  -------> ftp-data  ls command
dyn3  <------- ftp-data  ls command
dyn dynamyc ports 1025-65535
ftp=21 ftp-data=20 auth=113