By Scott Jones, Managing Director, and Nathan Sharp, Senior Business Manager; Embedded Security, Maxim Integrated
From syringe infusion pumps to pacemakers, the types of medical devices that raise security concerns are growing as these devices become more intelligent and more connected. Cloning, counterfeiting, unauthorized reuse—these are just a few of the concerns that afflict any aspect of the internet of things (IoT). And for anyone undergoing a medical procedure, the last thing they want to have to worry about is whether the medical instrument being used has been compromised.
Despite the potential for harm, there’s growing concern that security is still lacking in medical devices. In a survey by the Ponemon Institute, 67% of hospital network security specialists answered “no” or “unsure” when asked if medical device security was on their short list of concerns, according to a Forbes article. Unfortunately, the medical field is not immune to believing the myths about implementing security that are pervasive in so many other sectors: that it’s too complicated, time-consuming, or expensive.
Medical Endpoints Need to Be Protected
Thanks to the integration of technologies like wireless connectivity, optical biosensors,and near-field communication (NFC), portable, implantable, ingestible, or wearable devices are enabling patients and healthcare professionals to continuously track an array of health parameters. The emergence of these capabilities is enabling a more proactive and coordinated approach to healthcare, while helping to streamline costs.
Without protection from hacking, however, medical endpoints, including tools, sensors, and consumables, can succumb to:
- Counterfeiting
- Reuse beyond their targeted lifecycle
- The introduction of viruses or harmful configuration data
Fortunately, medical device designers don’t need to be cryptography experts in order to protect their connected devices. The market now offers a variety ofsecurity ICsthat can be integrated into embedded designs to alleviate many of the threats. Some of these devices provide an unmodifiable root of trust that allows developers to close off more potential entry points into their design than a software-based approach would allow. For instance, in a microcontroller, the root of trust could be startup code stored in internal immutableROM, which can be used to verify and authenticate an application’s software signature when the microcontroller is powered on.
For an even stronger level of security, physically unclonable function (PUF) technology is available. PUF circuitry uses the random electrical properties of IC devices to produce a unique and repeatable root cryptographic key for each IC. Taking advantage of this variability, PUF circuits can extract secret information that is unique to each chip. Thesecret, or key, is generated only when needed, and it isn’t stored on the chip. A device designed with PUF technology, featured in some secure authenticators, is protected from invasive attacks.
Secure authenticators also provide other features that can be advantageous for smart, connected medical devices: traceability, secure monitoring, usage monitoring, and protection against counterfeiting. For example, the challenge-and-response authentication that these ICs provide can ensure that a surgical tool is authentic and hasn’t been used before.
Another consideration for medical instruments is sterilization. Gamma and e-beam sterilization deliver high levels of radiation, which can disrupt or damage certain types of nonvolatile memory. A critical component of secure authenticators, memory stores sensitive information such as keys, application data, and certificates. Nonvolatile memory typically stores calibration and manufacturing data. Now there’s a secure authenticator that provides radiation-resistant bi-directional authentication. Maxim’s DS28E38 is the industry’s first radiation-resistant, 1-Wire® secure authenticator for medical surgical tools or sensors that undergo gamma or e-beam sterilization. Resisting up to 75kGY of radiation, the DS28E38 features an array of protective capabilities, including ECDSA P256 asymmetric secure authentication, SHA-256 hash-based message authentication code (HMAC) symmetric key secure authentication, and elliptic-curve Diffie-Hellman (ECDH) key exchange for optional secure session keys between host and slave authenticator communication.
Safeguard Against Hacking with Security ICs
Many people are taking more proactive control over their well-being, tapping into a personalized stream of health-related data from their smart, connected medical devices. Since connectivity does open up these devices to the possibility of malicious attack, device designers would benefit from integrating security ICs into their designs. It’s good medicine.
