Abstract
A basic requirement for a modern communications system is the protection of the communications services provided and of the information transmitted through them. This consists of a set of security measures and procedures organized in accordance with the legal provisions in force within each military structure, for the protection of the stored, processed and transmitted information through communications and informatics systems against threats and actions/inactions that may affect their confidentiality, integrity, availability and authenticity or may affect the operation of communications and informatics systems. In these circumstances, the development of communications equipment and the growing integration of the related technical equipment is accompanied by the emergence of numerous means and processes whereby unauthorized access to classified information may be achieved, both by direct interception of the traffic - especially the one transmitted by electromagnetic waves and the unintended (parasite) radiation of the communications and computing equipment. Therefore, a secure communications system within the modern battle space cannot be concieved without technical equipment needed to protect classified information, mainly based on automatic encryption and on appropriate organizational measures