Please find the latest ULP Winter 2017 Quarterly from www.nordicsemi.com.
Integra Systems, Inc., has worked with Nordic for many years on unique product development efforts for the medical device space using both ANT www.thisisant.com and BTLE. , as well as the WLAN. This however is the first issue of ULP Quarterly that “really highlights” the huge growing BTLE medical device market space.
While Bluetooth has been around for a long time. The advent of the “smart-phone” with BTLE, the Bluetooth SIG driving improvements to now the release of 5.0, the connectivity convergence has now arrived for healthcare and medicine big time in 2017. The momentum will continue in 2018. Consumers also are demanding the connectivity as well from glucose meters to in-ear wireless temperature measurements for babies. The smart phone, the application, and the “connected” device, brings it all together. (Page 3)
Some interesting highlights that sets the tone for continued medical device product development for BTLE. “The FDA has approved the first drug in the United States with a digital ingestion tracking system”. The patch sends data, i.e. dosage and when the pill was taken via Bluetooth Low Energy to a smart phone application allowing patient’s and caregivers to track the ingestion of medication. (Page 11).
Everybody is concerned today about security. By the nature of BTLE and FHSS, BTLE is considered a secure protocol. While security has greatly increased over the improvements in BTLE and now 5.0, design and development efforts may want to consider the addition of an ARM TrustZone CryptoCell-310 Cryptographic module and an AES 128-bit hardware accelerator. This can provide support for a wide range of asymmetric, symmetric, and hashing cryptographic services for secure applications. In BLTE 4.2 an asymmetric encryption scheme was introduced called “secure connections”. This revision of the BTLE specification included an algorithm that generated a private key using an Elliptic key exchange method making it almost impossible to intercept.
https://www.arm.com/products/security-on-arm/trustzone-security-ip
Just like Wi-Fi, “man in the middle” attacks can pose a security to BTLE. OOB commissioning was introduced as a part of Bluetooth 4.0. This moved authentication away from the usual Bluetooth LE channels to an “out-of-band” channel which remains unknown to the prospective hacker. It seems that NFC (Near Field Communications) offers the best balance of security, but also user friendly for the implementation of the OOB channel.
NFC devices exchange information in the 13.56 MHz ISM band at rates ranging from 106 to 424kbps. Bidirectional interaction is established by bringing the devices within 4 to 10cm of each other. The NFC link can be used as the OOB channel to start the pairing process and look after authentication. Once this handshake commissioning process is completed, then communication switches to the secure Bluetooth LE link.
The value to NFC for the OOB channel is the very short distance which would make hacking via a man in the middle intercept very difficult to reveal their intent. Finally OOB commissioning also stops unwanted devices from establishing a connection with the user’s permission. From a user’s standpoint, there is no need to enter or verify a passcode.
