1. Issues

Among IT security issues, the problem of denial-of-service attacks has become a major topic over the last ten years. In a survey of a large group of IT security professionals, 29% were victims of such attacks between 2009 and 2010. Over the past five years, this figure has remained relatively stable: between 21% and 32%.

Early definitions of denial of service, such as ISO's, mainly linked denial of service to preventing a user from accessing a service or delaying its use in an unacceptable way. Can we equate denial of service with any situation where customers' legitimate access to services becomes impossible? The answer is obviously no. There are many possible causes for this, and the only distinction that can be made is whether the person causing the problem intends to cause harm. This notion of "will to harm" has been taken into account in subsequent definitions....