Security Issues in Special-Purpose Digital Radio Communication Systems: A Systematic Review

For applications where general-purpose communication systems, such as mobile telephony, do not satisfy user requirements, special-purpose digital wireless communication standards have been developed. Since these systems often support critical infrastructures, security issues can have far-reaching consequences. To study the extent of research on security issues in specialized communication standards, a systematic literature review was performed, using snowballing to maximize coverage. The found publications cover security issues in radio communication systems for three major areas: civil transportation, public safety and security, and telephony and satellite communication systems. The main results from the included publications are summarized. This is followed by an analysis that presents five common themes among the security issues: lack of encryption, lack of authentication, broken encryption, protocol vulnerabilities, and implementation vulnerabilities. Research tools and methods used across the different technology fields are systematized, showing that software-defined radio and open-source software appear to be enablers of research on the communication standards covered by the review. The systematization also reveals that the application of research methods to different standards is spotty. Finally, numerous open research directions are pointed out, including the need for more holistic research that goes beyond just finding technical flaws in single standards.