Patent ID: 7031328

Claim:
A method in an IPv6 mobile router, the method including: first generating an IPv6 tag address that includes a prescribed protocol identifier for an IPv6 gateway configured for transferring packets between an IPv4 network and an IPv6 network, and a public IPv4 gateway address for the IPv6 gateway; second generating an IPv6 packet having a source address field that specifies the IPv6 tag address, and a reverse routing header that specifies a home address; encapsulating the IPv6 packet in an IPv4 packet having an IPv4 header including a destination address field that specifies the public gateway IPv4 address and a source address field specifying a mobile router IPv4 address, the mobile router IPv4 address used by the IPv6 mobile router for accessing the IPv6 gateway via the IPv4 network; and outputting the IPv4 packet to the IPv6 gateway via the IPv4 network, for transfer of the IPv6 packet onto the IPv6 network.