A digital bus is a shared communication pathway that lets onboard computers and sensors exchange data over the same wiring or protocol network. Instead of every device talking point-to-point, a bus carries messages between many systems, often with rules for timing, priority, and message format.
In cyber security, digital buses matter because they are the nervous system of many cyber-physical platforms, including aircraft, vehicles, and industrial equipment. If an attacker can inject, replay, or corrupt bus traffic, they may influence displays, controls, or safety logic without touching the hardware directly. Defenders therefore look for strong segmentation, message authentication, monitoring for abnormal traffic, and strict control over connected devices. In aviation, a bus can also be an attack surface in lab testing, where researchers study how subsystems trust one another and whether unexpected messages can change system behavior.