Patent ID: 8417831

Claim:
A network system adopting a first IP protocol, the network system comprising: an address allocating server and a communication terminal supporting both the first IP protocol and a second IP protocol different from the first IP protocol, the address allocating server dynamically allocating an address of the second IP protocol to the communication terminal, characterized in that: said communication terminal comprises: a dynamic address manager for acquiring said dynamically allocated address of the second IP protocol of said communication terminal from the address allocating server such that the address of the second IP protocol is temporarily acquired and then released after a specified time interval and acquiring a second IP protocol address of a destination of a second IP protocol packet from a second IP protocol application, and an address adapter for encapsulating the second IP protocol packet from the second IP protocol application into a first IP protocol packet, wherein the second IP protocol address of said communication terminal, included in a header of the second IP protocol packet, and the second IP protocol address of the destination are encapsulated into said first IP protocol packet; wherein said address adapter further comprises: an address-mapping table for storing a correspondence between the first IP protocol address and the second IP protocol address; an address-mapping table manager for managing the address-mapping table; a packet translator for transforming the first IP protocol packet into the second IP protocol packet or transforming the second IP protocol packet into the first IP protocol packet, according to the correspondence stored in the address-mapping table; wherein said first IP protocol packet is either an IPv4 packet or an IPv6 packet, said second IP protocol packet is an IPv6 packet when said first IP protocol packet is an IPv4 packet and said second IP protocol packet is an IPv4 packet when said first IP protocol packet is an IPv6 packet.