Hi all valued members!

I am using Asus DSL N12u B1 with a 3g Usb Dongle (Micromax MMX 352G)

my DSL is acting as a router in this configuration.

I can successfully browse internet but whenever I try to register for DDNS service from the router configuration page,

router says:
"The Wireless router currently uses a private WAN IP address.
This router may be in the multiple NAT envionment and DDNS service cannot work in this environment"

I also checked the WAN IP in the router and it was 100.XXX.XXX.XXX and not a private IP.

But when I checked with whatismyip.com it was showing my ip as 106.XXX.XXX.XXX
I am not able to access my public IP(106.XXX.XXX.XXX) from another network also.

please provide me some inputs so that i can resolve this problem.