2.29.30.0 is a public address assigned to Orange / Wanadoo. The Livebox is a router provided by Orange.
The .0 doesn't look right, unless Orange are doing something a little creative.
2.29.30.0 could be a valid the default route though
Try visiting http://www.whatsmyip.org
To check what your outside address really is.
I feel I need to now ask, why do you need this address?
It might help to fathom which address you should be looking at.