The Concept of Trust in the Integration of Information Systems

The integration of information systems is an inevitable reality, because it gives a competitive advantage and allows you to reduce business costs. Information security problems that arise during integration are usually solved by establishing trust. However, the concept of trust itself, as it turned out, has not been studied and formalized, which makes it difficult both to theoretically study this phenomenon and to use it in practice. The purpose of the article is to formalize the concept of trust in information systems on the basis of existing theoretical studies and practical experience. Trust is considered as a measure of security as opposite to risk that is considered as a measure of danger. The functional structure of trust is presented. A statement about the necessary and sufficient condition for the existence of trust in an information system is formulated and proven by the resolution method. The offered concept of trust is equally well applicable to software, hardware, personnel, documents etc.