Since 2013, the installation rate of digital key features such as “keyless entry” and “remote start” in newly launched car models has gradually increased, rising from no installation initially to the current 27.75% and 37.50%. Today, we will discuss digital keys.

Differences Between Digital Keys and Conventional Car Keys

• Different Key Form: Traditional car keys are integrated remote control keys, while digital keys do not have a physical form and can be accessed through a smartphone or smart wearable device, allowing key functions to be performed by simply approaching the vehicle.
• Different Features: Conventional car keys are used solely for locking and unlocking doors, whereas digital keys offer keyless entry and start, remote key authorization, personalized vehicle settings, and additional functions such as locking/unlocking, starting, opening/closing windows, controlling air conditioning, and vehicle sharing through smart devices.

Digital Key Technology Principles Digital keys primarily employ three technology pathways: Bluetooth low-energy (BLE), near-field communication (NFC), and ultra-wideband (UWB), with Bluetooth keys being the most widely used.

Bluetooth BLE (Bluetooth low-energy) Key

Bluetooth BLE keys are relatively straightforward. Vehicle owners add their mobile phone numbers in the digital key management interface, download the app to create the key, and then use it. Bluetooth keys typically work within a range of 15 meters in open spaces, have low power consumption, and are a mature technology. However, their performance may vary due to factors like the smartphone used and environmental interference. Additionally, compatibility issues may arise with different phone models and car brands due to hardware differences.

NFC Key

NFC keys involve using a device (e.g., a phone or a wearable) with NFC functionality near a specific area of the vehicle (e.g., B-pillar or exterior rearview mirror) to activate the key. Unlike Bluetooth keys, NFC unlocking can function even when the phone is low on battery.

UWB Key

UWB technology keys use ultra-wideband, a carrierless communication technology, for precise ranging. When close to the vehicle, UWB keys combine multiple anchor points in the vehicle with a legitimate handheld key or phone to achieve precise spatial perception of the vehicle. The vehicle autonomously adjusts welcoming lights, seat position, unlocks doors when approaching, and locks the vehicle when moving away, based on spatial perception changes.

Currently, the trend in digital keys is to combine Bluetooth and ultra-wideband (UWB) to enable keyless access and engine start from compatible mobile devices. Low-energy Bluetooth is used to verify the digital key between the vehicle and the mobile device, which creates and stores the digital key within a secure module, providing the highest level of protection against hardware or software-based attacks. UWB offers secure and precise high-accuracy distance positioning, allowing the vehicle’s location to be transmitted to authenticated mobile devices, safeguarding against network attacks.

More importantly, UWB data exchange generates critical encryption parameters in the secure module to ensure the highest level of security for positioning the device to the vehicle, authorizing user access, and driving the vehicle.

Is Cyber Security a Concern for Digital Keys?

The answer is yes. To some extent, digital keys can be considered products of the Internet of Things (IoT), and if the IoT is compromised, the consequences could be more severe than those of the internet. Therefore, information security is another crucial focus.

Digital key security primarily encompasses three areas: backend security, the security of mobile devices and controllers, and the security of communication links between the vehicle, mobile device, and backend. Only when digital keys have sufficient security guarantees can they be installed in vehicles on a large scale.

As an example, as early as 2016, hackers in the United States and domestic teams had already cracked models such as the Jeep Cherokee and the Tesla Model S. In one example, a hacker team used software like Ubertooth to crack the vehicle’s Bluetooth PIN code. Once successful, they connected to the Bluetooth system using a mobile device and exploited vulnerabilities between the keyless entry system and the mobile app control program, unlocking the car doors and starting the vehicle.

For the automotive industry, digital keys will play a crucial role in future developments, particularly in the era of autonomous driving. Digital keys are expected to become more intelligent, providing users with a better experience.