More and more critical business processes in commercial environments are being supported by electronic data processing. It is therefore vital to ensure the permanent availability of the IT infrastructure. Undisturbed workflow operation is the key to success regardless of whether the operation involves e-mail communication or ERP systems. The spiralling growth of threats from worms, viruses, Trojans, spam, DoS attacks and hackers is resulting in immense costs every year. These are cutting productivity and even threatening many business’ very existence.