Secure Status Updates under Eavesdropping: Age of Information-based Physical Layer Security Metrics
This work addresses security and timeliness issues in wireless communication systems for applications like IoT and real-time monitoring, but it is incremental as it builds on existing wiretap channel models and age of information concepts.
The paper tackles the problem of maintaining information freshness in wireless status update systems under eavesdropping attacks by defining two new age of information-based secrecy metrics and proposing a randomized stationary transmission policy to enhance secrecy performance, with simulation results validating the analysis and optimization.
This letter studies the problem of maintaining information freshness under passive eavesdropping attacks. The classical three-node wiretap channel model is considered, in which a source aims to send its latest status wirelessly to its intended destination, while protecting the message from being overheard by an eavesdropper. Considering that conventional channel capacity-based secrecy metrics are no longer adequate to measure the information timeliness in status update systems, we define two new age of information-based metrics to characterize the secrecy performance of the considered system. We further propose, analyze, and optimize a randomized stationary transmission policy implemented at the source for further enhancing the secrecy performance. Simulation results are provided to validate our analysis and optimization.