Energy-Aware Key Exchange for Securing Implantable Medical Devices

Abstract

Implantable medical devices (IMDs) continuously monitor the condition of a patient and directly apply treatments if considered necessary. Because IMDs are highly effective for patients who frequently visit hospitals (e.g., because of chronic illnesses such as diabetes and heart disease), their use is increasing significantly. However, related security concerns have also come to the fore. It has been demonstrated that IMDs can be hacked-the IMD power can be turned off remotely, and abnormally large doses of drugs can be injected into the body. Thus, IMDs may ultimately threaten a patient's life. In this paper, we propose an energy-aware key exchange protocol for securing IMDs. We utilize synchronous interpulse intervals (IPIs) as the source of a secret key. These IPIs enable IMDs to agree upon a secret key with an external programmer in an authenticated and transparent manner without any key material being exposed either before distribution or during initialization. We demonstrate that it is difficult for adversaries to guess the keys established using our method. In addition, we show that the reduced communication overhead of our method enhances battery life, making the proposed approach more energy-efficient than previous methods.

Information Theoretic Key Agreement Protocol based on ECG signals

“…In particular, in [8], fuzzy-vault based protocol was shown to shorten the key establishment time by reducing the number of IPIs needed to generate a secret key. In [9], an energy-efficient key exchange protocol using IPIs was able to generate a secret key in an authenticated and transparent manner, without any key material being exposed before distribution or during initialization. The authors could dramatically reduce energy consumption (in communication and computation) compared to the state-of-the-art (e.g., [7]), while keeping secure key exchange.…”