| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a network system and a security device capable of enhancing network security by simply controlling the network communication. <P>SOLUTION: The network system includes: a router 5 that relays the communication between an internal network 4 and an external network 3; a client 6 connected to the internal network 4; and a security device 1 that monitors the communication between the router 5 and the client 6. The security device 1 includes: a router advertisement alteration section 14 that changes a content of a router advertisement transmitted by the router 5 so that the client 6 sets the security device 1 as a default gateway; and a router advertisement transmitting section 16 that transmits the router advertisement changed by the router advertisement alteration section 14 to the client 6. <P>COPYRIGHT: (C)2013,JPO&INPIT |
