Crypto-Aided MAP Test for Low-Latency Detection of False Data in Short Packets

Cryptography has been used as the first line of defense to ensure data integrity. However, it incurs a significant overhead for short packets which represent the most common form of traffic in emerging applications, such as the Internet of Things. In this paper, we propose an interdisciplinary framework for detecting false data in short packets that are collected from multiple sources through a relay. The proposed scheme performs a lightweight cryptographic integrity check that employs a short message authentication code, thereby reducing the overhead for data integrity, followed by the maximum
a posteriori
(MAP) test at the physical layer that detects any remaining false data that the cryptographic integrity check misses. This interdisciplinary approach interplays between the cryptographic integrity check and the physical-layer integrity check to assure the data integrity of short packets with reduced overhead and low latency. The proposed scheme can also provide a significant reduction in the average probability of detection error over the traditional cryptographic integrity check.