Data Security in Health Information Systems by Applying Software Techniques

The problems encountered in achieving data security within computer-supported information systems increased with the development of modern computer systems. The threats are manifold and have to be met by an appropriate set of hardware precautions, organizational procedures and software measures which are the topic of this paper. Design principles and software construction rules are treated first, since the security power of a system is considerably determined by its proper design. A number of software techniques presented may support security mechanisms ranging from user identification and authentication to access control, auditing and threat monitoring. Encryption is a powerful tool for protecting data during physical storage and transmission as well.

Since an increasing number of health information systems with information-integrating functions are database-supported, the main issues and terms of database systems and their specific security aspects are summarized in the appendix.

Mit der Entwicklung moderner Rechnersysteme wuchsen die Probleme zur Gewährleistung des Datenschutzes in rechnergestützten Informationssystemen. Den vielfältigen Risiken muß mit einer geeigneten Kombination von Hardware-Einrichtungen, organisatorischen Verfahren und Software-Maßnahmen, welche Gegenstand dieses Beitrags sind, begegnet werden. Entwurfsprinzipien und Regeln für die Software-Konstruktion werden zuerst behandelt, denn der Sicherheitsgrad eines Systems wird entscheidend durch einen guten Entwurf bestimmt. Eine Reihe von Software-Techniken unterstützen Sicherheitsmechanismen, die sich von der Benutzer-Erkennung bis zur Zugriffskontrolle und -protokollierung erstrecken. Einen wirksamen Schutz bei der Speicherung und auch während der Übertragung der Daten stellt das Kryptieren (Chiffrieren) dar.

Da eine zunehmende Zahl von medizinischen Informationssystemen mit Funktionen der Informations-Integration durch Datenbanken unterstützt werden, sind im Anhang die wesentlichen Begriffe und Konzepte der Datenbanksysteme sowie ihre spezifischen Datenschutz-Aspekte zusammenfassend dargestellt.

Key-Words:

Health Information System - Data Security - Software Technique - Database System - Access Control

Schlüssel-Wörter:

Gesundheitsinformationssystem - Datenschutz - Software-Technik - Datenbanksystem - Zugriffskontrolle

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