1. Introduction

One of the fastest developing subjects associated with applying modern information technologies to manage processes at commercial organisations comprises the acquisition, the flow as well as planning, controlling, analysing, designing and defining detailed actions which forms the main component of the information management process. Scientific research in this field is interdisciplinary in nature and based on knowledge of management, mathematics and information theory, particularly knowledge engineering. The significance and wide popularity of this subject has justified distinguishing a new line of research, called Information Management [1–4]. A new subject, namely the techniques for protecting and encrypting (hiding) important information and protected information [5], has merged with the line of research on the subject and problems of information management. The problems of information encryption and protection are rooted in cryptography, which mainly uses algorithms for ensuring data confidentiality and information division techniques, as well methods of reconstructing information.