Modern society is increasingly dependent on the security and reliability of IT systems and the Internet, but the vulnerability of our digital world is still proved painfully by hacker attacks on networks or databases, computer viruses, internet worms, and trojan horse attacks. In addition to these facts: the more sensible data like online orders, medical data, or electronic cash is transmitted in open networks like the Internet, the more targets exist for such attacks. So computer and network protection must be one of the most important objectives. This includes protection measures on the underlying network level upto the level of applications and data.
