Strategies to Protect Against Distributed Denial of Service (DDoS) Attacks
cisco.com
cisco.com
Nowadays, it's all about routing the target host through a series of high bandwidth/high processing filters to identify and drop the bad traffic. People don't use SMURF (haven't in over 5 years), and most floods are not ICMP anymore, they are mindless HTTP requests from seemingly "valid" looking zombie clients.