[LARTC] Aggregate 3 internet connexions.

[Jeremy SALMON]

Hi,

I have 3 internet connexions :
Router 1 : 192.168.212.2
Router 2 : 192.168.212.3
Router 3 : 196.200.8.73

I can't change IP adress of router 3 because I haven't admin password 
and my provider don't want to give it.

I want only 1 PC to aggregate the 3 connexions.

How I can make that Router 3 work on my 192.168.212.x network?

Thanks
Jeremy