Intermediary device and forwarding method

A intermediary device relays a data packet communicated between two networks. The intermediary device extracts a host name from the data packet transmitted from a transmission-source network, and translates the host name to an address in a transmission-destination network. This function allows an access to a plurality of servers in the transmission-destination network with respective host names. When the transmission-source network is a wide area network, address independent access is allowed because the host name is always constant even if a global IP address is updated. A directory can be placed after the host name, so that a common directory can be used for the plurality of terminals.