Router WAN IP diff from Public IP

[tony1l]

Trying to get my FTP server running, and nothing can connect when I discovered my router's WAN IP address reports 100.65.XXX.XXX while my public ip address is 50.115.XXX.XXX. I run No-IP ddns and its reporting (from my router) my IP as 50.115.xxx.xxx address. LAN is (192.168.0.1) scheme. My PC can FTP to itself using both localhost and 100.65.xxx.xxx, but nothing outside can connect to my FTP on 50.115.xxx.xxx. Plus I can't loop-back FTP from the host using the on 50.115.xxx.xxx.

I have no firewall except for Windows 7 firewall, and router's firewall (Dlink dir 655) both are disabled.
I've called my ISP to verify they aren't blocking port 21, they claim they aren't.
I've setup my router to forward ports 21, 22, and 990 along with a block 50000-51000, for passive mode.
I then setup my PC as a DMZ For testing only.
I've scanned my pc with GRC.com's Shields-Up website and it shows no open ports on 50.115.xxx.xxx
I've used FileZilla's test FTP connection, nothing connects.

Any suggestions?

Thanks
-Tony

[botg]

You are behind carrier-grade NAT. As result you simply cannot host servers over IPv4.

[boco]

Carrier Grade NAT is often used in IPv6 transition techniques such as DS-Lite. If you have a connection using DS-Lite, hosting servers is only possible over IPv6.

If you have only IPv4 and are behind carrier grade NAT, you cannot host server at all (as you cannot configure the ISP firewall).