| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To obtain a network system capable of identifying a attack source of DoS (denial of service) attack, and relaying normal traffics without troubles, while suppressing consumption of network resources by illegal traffics, even when fraudulent traffics are generated due to DoS attack. <P>SOLUTION: This network system is provided with a plurality of routers (11, 12, 13, 14, 15, 21, 22 and 23), which cooperate in requesting the adjacent routers to monitor packets with each other, in order to take countermeasures against the DoS attack targeting servers over the Internet. Each of the routers which are requested to monitor the packets detects the attacker packets matching a specific bit pattern, thereby tracing the transmission source of the attack packets. <P>COPYRIGHT: (C)2004,JPO</p> |
