| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an authentication system for a communication device that enables only a permitted right communication device to communicate with a network side such as the Internet by disabling an illegal communication device to communicate with the network side even when the illegal communication device impersonates a permitted communication device. <P>SOLUTION: The communication device 102 when successfully authenticated by an authenticating device 101 transmits a network address confirmation packet 201 of ARP, RARP, etc., by an illegal terminal detector 103 to check whether the MAC address or IP address of the device itself is used as a false address. The illegal communication device 25 impersonating the communication device 102 has the same address with the communication device 102, so the illegal communication device 205 sends an answer packet 202 back. The illegal terminal detector 103 receives the answer packet 202 to recognize that the communication device 105 having the same address with the device itself is present on the same network. <P>COPYRIGHT: (C)2008,JPO&INPIT</p> |
