Are you concerned with Layer 7 Denial of Service?
With the discovery of the denial of service methods of HTTP GET ("Programming Model Attacks" section of Apache Security) and HTTP POST methods discussed at a single machine can be utilized to conduct a denial of service against web servers such as Microsoft IIS and Apache - Slides
Using a risk based approach, DO YOU CARE about DoS? Are your systems able to defend against this type of availability attack? This tool was created and released GPLv3 Open Source under the OWASP Foundation umbrella for testing of systems and controls.
If you want to learn more about ways to mitigate this attack technique for Apache look at the OWASP Project Page
Download link: HERE
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