APPLICATION OF SPOOF RESISTANT AUTHENTICATION PROTOCOL OF SPACECRAFT IN LOW EARTH ORBIT SYSTEMS OF SATELLITE COMMUNICATION

Efficient application of low Earth orbit (LEO) satellite communication systems (SCS) is clearly demonstrated in remote monitoring and control complexes of nonmaintainable facilities intended for production and transportation of hydrocarbons in the Far North. In order to arrange continuous communication with such facilities SCS is comprised of from 48 to 60 spacecrafts. Increase in the number of such orbital constellations can lead to situation when an alien satellite would attempt to impose previously intercepted command to receiver located on non-maintainable facility. As a consequence, the intercepted and imposed control command would shut down the oil production facilities, thus impairing Arctic wild landscape. In order to prevent such situation, it is proposed to apply Identification-Friend-or-Foe system (IFF system) of spacecraft (SC). It is obvious that spoof resistance of such system depends mainly on authentication protocol. Aiming at reduction of time consumptions for authentication, this article proposes to use modular codes. In such codes computations are carried out in parallel according to code modules and independent on each other. The aim of the work is increase in execution of question/answer authentication protocol by means of modular codes.