[WTA]Streamyx IP, Trying to setup DDNS

Hi forumers,

I'm trying to set up a DDNS on my Streamyx line.

I have question on my dynamic IP address I get from my modem and from whatismyip.com which is totally different.

Isn't it suppose to be the same IP on my WAN interface and from what I get from whatismyip.com?

I tried to ping the IP i got from whatismyip.com with 'request timed out' result but no problem using WAN from my modem.

any ideas ?

Thanks