This is the path we CISCO2600 device on the Internet through NAT, only one outside the IP network, like mapping an FTP server, do the following operations :
Senat inside source static tcp 192.168.168.2 ip 21 xxx.xxx.xxx.xxx (external network IP) 21

However, the visit is not ftp:\\xxx.xxx.xxx.xxx
Ftp:\\192.168.168.2 no problem with Network Access
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