A data center comprises a first gateway that connects with a terminal using a VPN (Virtual Private Network) through a wireless LAN and a first wide area network, a second gateway that connects to a second wide area network (WAN2), a virtual network connected to the first gateway and the second gateway; and a function block that is provided between the first gateway and the second gateway and that performs filtering of at least one of a packet input from the first wide area network side and a packet input from the second wide area network.