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+The `ip64` module lets an IPv6 Contiki network be connected to an IPv4
+network without any additional configuration or outside software. The
+`ip64` module runs on the RPL root node and translates outgoing IPv6
+packets into IPv4 packets nd incoming IPv4 packets to IPv6 packets.
+
+The `ip64` module uses stateful NAT64 (RFC6164) to do the packet
+translation and DNS64 (RFC6147) to catch DNS requests for IPv6
+addresses, turn them into requests for IPv4 addresses, and turn the
+replies into responses for IPv6 addresses. This allows devices on the
+inside IPv6 network to connect to named servers on the outside IPv4
+network.
+
+The `ip64` module hooks into the IPv6 stack via a fallback
+interface. Any packet that can not be routed into the local RPL mesh
+will be sent over the fallback interface, where `ip64` picks it up,
+translates it into an IPv4 packet, and sends it over its outgoing
+interface.
+
+In addition to providing NAT64 and DNS64 services, the `ip64` module
+also performs DHCPv4 to request IPv4 address for devices connected to
+a medium such as Ethernet. The `ip64` module also performs ARP
+processing to communicate over the Ethernet.
+
+The `ip64` module uses a configuration file called `ip64-conf.h` that
+specifies what device to use for the IPv4 network. This file is
+intended to be placed in the platform directory. An example
+configuration file called `ip64-conf-example.h` is provided in this
+directory.
+