"Name me one brand of standard of the shelf
routers that supports IPIP"
Cisco
Juniper
Mikrotik
By the way,
<http://etutorials.org/Networking/Integrated+cisco+and+unix+network+architectures/Chapter+11.+VPN+Technologies+Tunnel+Interfaces+and+Architectures/IP-IP+Tunnel/>
has a tutorial/lab on setting up IPIP tunnels on both Cisco and
Linux systems.
- Brian