In order to understand the spoofing abilities of attackers today, we first examine
results from the Spoofer Project [MIT Advanced Network Architecture
Group 2007; Beverly and Bauer 2005]. This project attempts to measure the
ability of hosts throughout the Internet to send spoofing packets. We will show
that IP source address spoofing remains a severe problem on the Internet. Although
many may feel the network community solved the spoofing problem
through the widespread adoption of ingress and egress filtering, attackers can
still spoof a significant portion of existent IP addresses, often any IP address.