Consider a scenario where a computer in a large network, such as a university, starts (D)DoS attack by spoofing its IP address against a public server (victim). At best, if an IP traceback technique has been utilized in both the university network and the victim side, the victim would be able to identify that the attacker’s network is the university network. When the victim starts filtering out any traffic from this network, many computers at the university network that have not been involved in the attack will also be filtered out. In general, there are two ways for routing the network traffic from a local network to the Internet: