Carnegie Mellon University: "Denial of Service"
Read this page. While you read, try to explain the modes of DoS attacks, such as consumption of scarce resources, configuration information alternation, and physical destruction. For DDoS attacks, describe the tools that are used for DDoS, why the DDoS attacks are possible, and the protocol vulnerabilities that are used in DDoS attacks.
Click https://web.archive.org/web/20160606093409/http://www.cert.org/information-for/denial_of_service.cfm link to open resource.