The number of intrusions and attacks against critical
infrastructures and other information networks is increasing rapidly.
While there is no identified evidence that terrorist organizations are
currently planning a coordinated attack against the vulnerabilities of
computer systems and network connected to critical infrastructure,
and origins of the indiscriminate cyber attacks that infect computers
on network remain largely unknown. The growing trend toward the
use of more automated and menacing attack tools has also
overwhelmed some of the current methodologies used for tracking
cyber attacks. There is an ample possibility that this kind of cyber
attacks can be transform to cyberterrorism caused by illegal purposes.
Cyberterrorism is a matter of vital importance to national welfare.
Therefore, each countries and organizations have to take a proper
measure to meet the situation and consider effective legislation about