Chapter 11 IPsec VPN for FortiOS 5.0 : IPv6 Features : IPv6 Network Address Translation : NAT64 and DNS64 (DNS proxy)
  
NAT64 and DNS64 (DNS proxy)
NAT64 is used to translate IPv6 addresses to IPv4 addresses so that a client on an IPv6 network can communicate transparently with a server on an IPv4 network.
 
NAT64 is usually implemented in combination with the DNS proxy called DNS64. DNS64 synthesizes AAAA records from A records and is used to synthesize IPv6 addresses for hosts that only have IPv4 addresses. ‘DNS proxy’ and ‘DNS64’ are interchangeable terms.
Figure 288: Example NAT64 configuration
With a NAT64 and DNS64 configuration in place on a FortiGate unit, clients on an IPv6 network can transparently connect to addresses on an IPv4 network. NAT64 and DNS64 perform the IPv4 to IPv6 transition, allowing clients that have already switched to IPv6 addresses to continue communicating with servers that still use IPv4 addresses.
To enable NAT64 and DNS64, use the following CLI command:
config system nat64
set status enable
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