Abstract
In the rapid penetration of advanced and highly networked information society, it is necessary to assure the safety of computer systems at the wide-area disaster in the inner city district of Tokyo. We examined distribution and concentration of computers that take the important roles in business activities and administrative activities from introduction records. They stand evenly on intensity 6 upper and intensity 6 lower ground of the earthquake intensity map and we found comparatively high concentration around the representative business district of Tokyo. This result is that it is important to make infrastructures secure and to enhance the credibility of infrastructures of the representative business district of Tokyo would contribute to assuring the safety of computer systems at the wide-area disaster in the inner city district of Tokyo.
