How Secure Authenticators Ensure Patient Safety

January 9, 2019

Christine Young  By: Christine Young
 Blogger, Maxim Integrated 


The things around us—including medical devices—are getting smarter. There’s good and bad to this. On one hand, it’s hard to argue with the advantages of being able to be more proactive about healthcare. A patient with a smart, WiFi-enabled implanted pacemaker can, for example, send the wealth of useful data that the device continually collects directly to his or her doctor via a smartphone. Armed with this information, the doctor can more quickly (and remotely) evaluate the patient and potentially detect issues of concern. At the same time, however, connected pacemakers are vulnerable to hackers, who, with remote control over the devices, could create dangerous situations for the patients.

According to Allied Market Research, the internet of things (IoT) healthcare market is expected to reach $136.8 billion by 2021, with the patient monitoring application segment anticipated to keep its lead position at $72.7 billion by that year. In October 2018, results from a survey conducted by KLAS Research and the College of Healthcare Information Management Executives found that 18% of provider organizations questioned had experienced malware attacks on medical devices over the 18 months prior. You’ve probably seen the headlines over the years, too, about defibrillators, pacemakers and medication infusion pumps either getting hacked or recalled because of security vulnerabilities. Bottom line: the risk is certainly there, and many of us could be impacted.

The U.S. Food & Drug Administration (FDA), meanwhile, has issued its Medical Device Safety Action Plan, which includes a section on how it can help advance medical device cybersecurity. Its guidance ranges from integrating cybersecurity measures at the product design and development stage to having a risk-management plan in place through the device’s lifecycle to facilitating greater sharing of cyber risk information and intelligence within the medical device community. Looking at this plan, it’s clear that, for medical device developers, ensuring that patient safety is a key consideration early on is a wise course of action.

Protect medical devices with secure authenticators

As smart medical devices become a more integral part of healthcare, it’s increasingly important that they are protected from hackers, unauthorized use, cloning, and other security threats

Hands Off, Hackers!
Security ICs present a robust way for designers to protect their medical devices. When created with crypto-strong authentication, secure authenticators can protect the device and the sensor supply chain from cloning and unauthorized use and also securely manage the device’s usage limits. Boston-based Admetsys took the hardware-based security approach when designing its artificial pancreas for use in hospital settings. The Admetsys artificial pancreas automates what is otherwise a manual, often imprecise process of patient glycemic control. The device works with insulin and dextrose cartridges. To safeguard its system against hacking and also ensure that the information accompanying the medication dispensed will be valid and accurate, the company’s engineers integrated three Maxim security ICs into their solution: the DS28E83 DeepCover® secure authenticator, the DS28E38 DeepCover secure authenticator, and a DeepCover secure microcontroller.

“In medical care, security is about patient safety,” said Jeff Valk, CEO of Admetsys. “Maxim’s security ICs, including the DS28E83 and DS28E38 secure authenticators, enable us to ensure that the medication cartridges for our artificial pancreas will be used as intended and deliver the right dosages to the right patients. These solutions are helping us create a practical standard of care, enabling high-precision infusion and real-time, continuous diagnostics while allowing the patient’s circulatory system to operate unaltered.”

The DS28E83 is a radiation-resistant, 1-Wire® secure authenticator that protects medical equipment processed through gamma or e-beam sterilization. The device can resist up to 75kGY of radiation and provides Elliptic Curve Digital Signature Algorithm (ECDSA) P256 asymmetric secure authentication, SHA-256 symmetric key secure authentication, and elliptic-curve Diffie-Hellman (ECDH) key exchange for optional secure session keys between host and slave authenticator communication. In Admetsys’s solution, the DS28E83 secures the system’s sterilized sensors. The DS28E38 secure authenticator features ChipDNA™ physically unclonable function (PUF) technology. Maxim’s PUF technology depends on the naturally occurring random analog characteristics of fundamental MOSFET devices to produce cryptographic keys. Since PUF is based on random physical factors that are introduced during the manufacturing process, it is virtually impossible to duplicate or clone. The unique binary value generated by each PUF circuit isn’t stored on the chip; it is generated only when needed. Even if someone were to attempt to conduct an invasive physical attack on a PUF circuit, the attack itself would change the electrical characteristics of the PUF circuit, further impeding the attempt. Admetsys uses the DS28E38 to protect its medical cartridges against invasive physical attacks. As for the secure microcontroller, the company uses it for secure storage of keys and certificates to ensure its device’s integrity and authenticity.

One of the advantages of protecting an embedded device with a security IC is that you don’t have to be a cryptography expert to take advantage of crypto-strong protection. So, when you’re considering your next smart, connected medical device design, make sure that security is at the top of your list of design requirements.