Packet communication method and apparatus and a recording medium storing a packet communication program

A packet communication system for a network system comprising a first network corresponding to a first communication protocol, a second network corresponding to a second communication protocol and a plurality of packet communication apparatuses connected to at least one of said first network and said second network, comprising:

• an address translation table for storing correspondences between first type network addresses compatible with said first communication protocol and second type network addresses compatible with said second communication protocol for said plurality of packet communication apparatuses, respectively;
• protocol conversion means for a packet transferred for communication between an application program compatible with the first communication protocol and said second network;
• and
• address translation means for performing address translation between said first type network address and said second type network address for a send destination address contained in said packet on the basis of said address translation table, to thereby perform header conversion between said first communication protocol and said second communication protocol for said packet.

A packet communication method in a network system comprising a first network corresponding to a first communication protocol, a second network corresponding to a second communication protocol and a plurality of packet communication apparatuses connected to at least one of said first network and said second network, comprising the steps of:

• in a first packet communication apparatus which is connected to said second network and in which an application program compatible with said first communication protocol can operate, storing correspondence between network addresses of a first type compatible with said first communication protocol and network addresses of a second type compatible with said second communication protocol for said plurality of packet communication apparatuses, respectively;
• and
• upon packet communication between said application program and said second network in said first packet communication apparatus, performing address translation between said first type network address and said second type network address for a send destination address contained in the packet on the basis of the correspondence of said network addresses, to thereby perform header conversion between said first communication protocol and said second communication protocol for said packet,
• wherein said first communication protocol is an IPv4 and said second communication protocol is an IPv6.

A packet communication method in a network system comprising a first network corresponding to a first communication protocol, a second network corresponding to a second communication protocol and a plurality of packet communication apparatuses connected to at least one of said first network and said second network, comprising the steps of:

• in a first packet communication apparatus which is connected to said second network and in which an application program compatible with said first communication protocol can operate, storing correspondence between network addresses of a first type compatible with said first communication protocol and network addresses of a second type compatible with said second communication protocol for said plurality of packet communication apparatuses, respectively;
• upon packet communication between said application program and said second network in said first packet communication apparatus, performing address translation between said first type network address and said second type network address for a send destination address contained in the packet on the basis of the correspondence of said network addresses, to thereby perform header conversion between said first communication protocol and said second communication protocol for said packet;
• and
• when said application program receives a packet corresponding to said second communication protocol from said second network in said first packet communication apparatus, converting a send destination address contained in said received packet from said second type network address to said first type network address on the basis of the correspondence of said network addresses, to thereby convert a header of said received packet from a header of said second communication protocol to a header of said first communication protocol.