ZyXEL Communications USG40 User Manual page 306

Figure 227 GRE Tunnel Example
IPv6 Over IPv4 Tunnels
To route traffic between two IPv6 networks over an IPv4 network, an IPv6 over IPv4 tunnel has to
be used.
Figure 228 IPv6 over IPv4 Network
IPv6
On the ZyWALL/USG, you can either set up a manual IPv6-in-IPv4 tunnel or an automatic 6to4
tunnel. The following describes each method:
IPv6-in-IPv4 Tunneling
Use this mode on the WAN of the ZyWALL/USG if
• your ZyWALL/USG has a public IPv4 IP address given from your ISP,
and
• you want to transmit your IPv6 packets to one and only one remote site whose LAN network is
also an IPv6 network.
With this mode, the ZyWALL/USG encapsulates IPv6 packets within IPv4 packets across the
Internet. You must know the WAN IP address of the remote gateway device. This mode is normally
used for a site-to-site application such as two branch offices.
Figure 229 IPv6-in-IPv4 Tunnel
IPv6
Chapter 10 Interfaces
IPv4
Internet
IPv4
IPv4
Internet
ZyWALL/USG Series User's Guide
306
IPv6
IPv6