Glossary (Definition of key terms used in the National Plan for Information Infrastructure Protection / in the present document) Information infrastructure The entirety of IT elements that are part of a given infrastructure. Interdependency The total or partial mutual dependency of several goods or services. IT security Ensures the availability, integrity, verifiability and confidentiality of information in the use of information technology. For this purpose, • ‘availability’ means the situation in which the necessary usability of information as well as IT systems and components is ensured; • ‘integrity’ refers to the exclusion of unauthorized and prohibited modifications of information as well as of IT systems and components; • ‘verifiability’ means the situation in which required or promised properties or features of information or transfer facilities can be verified by the user and vis-á-vis third parties; • ‘confidentiality’ refers to the exclusion of unauthorized obtaining or procuring of information. IT security products Products used to ensure compliance with IT security requirements, including virus scanners, firewalls, public key infrastructures (PKI), intrusion detection systems (IDS), and plug-ins for data encryption in e-mail clients, e.g. for PGP or S/MIME. IT security products help ensure protect software applications, processes, systems and/or data to a greater extent than would be possible without such products. Critical infrastructures Organizations and facilities of great significance for the community whose failure or impairment would cause a sustained shortage of supplies, significant disruptions of public order or other dramatic consequences. Page 18