Threat Modeling and Security Improvements for Ethernet-Based Avionic Networks

Avionic networks use various Ethernet-based network protocols, including Ethernet according to IEEE 802.3, ARINC 664 communication and time-triggered communication according to the SAE AS6802A standard. The aim of this work is to determine the security threats of these protocols and compare their security strengths and weaknesses. Based on these findings, technical security measures are developed to improve their security. In this paper, STRIDE is used as a threat modeling method to identify security threats. Data flow diagrams are created for each of the three network protocols to model the system. A total of 45 threats are identified, these can be broken down into 33 threats affecting standard IEEE 802.3 Ethernet networks, 26 threats for ARINC 664 networks and 37 threats for time-triggered AS6802A networks. This paper proposes eleven security measures, which can mitigate 27 (60%) of the identified 45 threats.