The network connection device

PROBLEM TO BE SOLVED: To provide a network connection device in which by connecting between different networks (e.g. connecting between 1394 networks, and connecting two 1394 networks through another network), data are easily transferred between terminal equipment which are connected to the respective networks. SOLUTION: Topology of a 1st network 201 is recognized to prepare 1st topology information, the 1st topology information and topology information of a 3rd network 203 are exchanged via a 2nd network 300. The 1st topology information and topology information of the 3rd network are stored, and new topology information sharing them based on the 1st topology information and the topology information of the 3rd topology information is prepared to recognize the topology of the 1st network 201.