FIREWALL DEVICE

摘要

PROBLEM TO BE SOLVED: To protect a first network from an attack via a wide-area network if data transmission from the first network to a second network is only requested in a network including the first network and the second network connected with the wide-area network.SOLUTION: A firewall device comprises: a first device section for inputting therein communication data from a first network; and a second device section for inputting therein a signal based on the communication data from the first device section and for outputting the communication data to a second network. At least one of the first device section and the second device section comprises a single direction communication unit for transmitting a signal only in a direction from the first device section to the second device section.