A method for maintaining connectivity between a mobile node and a corresponding node when the mobile node connects to a foreign network, wherein a home address was associated with the mobile node and a home agent node when the mobile node was within the home network, wherein the foreign network and the home network are Internet protocol version 6, IPv6, networks but the corresponding node is an Internet protocol version 4, IPv4, node, the method comprising: receiving at the home agent node connected to the home network a binding update message from the mobile node currently connected to the foreign network, the binding update message including an IPv6 care-of address of the mobile node assigned by the foreign network; determining by the home agent node that the IPv6 care-of address belongs to the foreign network, that the foreign network has a foreign network address translation 64, NAT64, node, and that the foreign NAT64 node has as a prefix to append to IPv4 addresses to generate virtual IPv6 addresses for any IPv4 nodes communicating with the mobile node while in the foreign network, wherein a NAT64 node translates data traffic between IPv4 and IPv6; and sending a prefix binding request message by the home agent node to a home NAT64 node on the home network to bind the prefix to the home address of the mobile node for translation between IPv6 and IPv4, whereby the home agent node provides to the home NAT64 node the binding information, including the foreign NAT64 node's prefix, that enables the home NAT64 node to translate between IPv6 and IPv4 formatted data packets, which are tunneled between the mobile node and the corresponding node, through concatenation of the prefix to the corresponding node's IPv4 address found in the source address field of those of the data packets traveling toward the mobile node, and through removal of the prefix from the corresponding node's virtual IPv6 address found in the destination address field of those of the data packets traveling toward the corresponding node; the method further comprising the steps of: receiving a data packet over a tunnel from the mobile node at the home agent node; decapsulating by the home agent node the data packet and detecting the foreign NAT64 node's prefix in the destination address field of the data packet; and tunneling by the home agent node the data packet to the home NAT64 node on the home network; and tunneling from the home agent node to the mobile node those of the data packets sent by the corresponding node to the mobile node, wherein these data packets have been translated by the home NAT64 node from IPv4 to IPv6 format and therefore have the corresponding node's virtual IPv6 address in their source address field. receiving at the home agent node connected to the home network a binding update message from the mobile node currently connected to the foreign network, the binding update message including an IPv6 care-of address of the mobile node assigned by the foreign network; determining by the home agent node that the IPv6 care-of address belongs to the foreign network, that the foreign network has a foreign network address translation 64, NAT64, node, and that the foreign NAT64 node has as a prefix to append to IPv4 addresses to generate virtual IPv6 addresses for any IPv4 nodes communicating with the mobile node while in the foreign network, wherein a NAT64 node translates data traffic between IPv4 and IPv6; and sending a prefix binding request message by the home agent node to a home NAT64 node on the home network to bind the prefix to the home address of the mobile node for translation between IPv6 and IPv4, whereby the home agent node provides to the home NAT64 node the binding information, including the foreign NAT64 node's prefix, that enables the home NAT64 node to translate between IPv6 and IPv4 formatted data packets, which are tunneled between the mobile node and the corresponding node, through concatenation of the prefix to the corresponding node's IPv4 address found in the source address field of those of the data packets traveling toward the mobile node, and through removal of the prefix from the corresponding node's virtual IPv6 address found in the destination address field of those of the data packets traveling toward the corresponding node; the method further comprising the steps of: receiving a data packet over a tunnel from the mobile node at the home agent node; decapsulating by the home agent node the data packet and detecting the foreign NAT64 node's prefix in the destination address field of the data packet; and tunneling by the home agent node the data packet to the home NAT64 node on the home network; and receiving a data packet over a tunnel from the mobile node at the home agent node; decapsulating by the home agent node the data packet and detecting the foreign NAT64 node's prefix in the destination address field of the data packet; and tunneling by the home agent node the data packet to the home NAT64 node on the home network; and tunneling from the home agent node to the mobile node those of the data packets sent by the corresponding node to the mobile node, wherein these data packets have been translated by the home NAT64 node from IPv4 to IPv6 format and therefore have the corresponding node's virtual IPv6 address in their source address field.