METHOD FOR CREATING TUNNEL NETWORK INTERFACE AND TRANSMITTING/RECEIVING PACKET USING TUNNEL NETWORK INTERFACE IN SERVER OF IPv4 NETWORK

摘要

A method for constructing a tunnel network interface in a server of an IPv4 network and transmitting/receiving packets by using a tunnel network interface are provided to transmit/receive packets to/from each terminal by using a single tunnel network interface established in an OS(Operating System) of a server. When a new terminal attempts a connection(201), a server establishes information for the new terminal in a single tunnel network interface(202). The server sets an output network interface with respect to an IPv6 address of the new terminal as the tunnel network interface(203), and establishes a tunnel for the new terminal(204). The server checks whether there is a request for transmission of an IPv6 packet from an application program(205). If there is a request for transmission of an IPv6 packet, the server searches an IPv4 address and UDP port information by using destination IPv6 information as a key value(206), establishes an IPv4 or IPv6_UDP header by using the searched IPv4 information and transfers it to an IPv4 stack(207). The server transmits the packet transferred via the IPv4 stack to a corresponding terminal(208). The server checks whether an IPv4 packet has been received from an arbitrary terminal located in an IPv4 network(209). If an IPv4 packet has been received, the server checks whether the received packet is an IPv6 or UDP_IPv6 tunneling packet(210). If the received packet is the IPv6 or UDP_IPv6 tunneling packet and if the received packet has been tunneled to an IPv4 header, the server removes the IPv4 header, and if the received packet has been tunneled to an IPv4_UDP, the server removes a UD P header from a UDP stack(212). The server sets a packet reception interface as a tunnel network interface(213) and transfers the IPv4 header or IPv4_UDP header-deleted IPv6 packet to a reception processing routine of the tunnel network interface(214).