How does Apple's new 3D Face Recognition System work and can we trust it? As well as technically, ethically and conveniently, the iPhone X rebates the cards of securing electronic devices.
"Can we trust Face ID? "This is certainly the question that comes up most often about the new security system for iPhone X." How does this three-dimensional facial recognition, led to replace Touch ID in the next few years? Is another. Although the demonstration at the last keynote was convincing, it raises many questions.
Like its predecessor, Face ID would be impossible without a very close union between hardware and software. For this, Apple has developed a set of components called TrueDepth. Located on the front in the notch made at the top of the screen, it gathers several sensors analyzing the face. There is a spotlight that sends more than 30,000 to map the face. An infrared illuminator illuminates the face to help identify it even in the dark.
No visible light emitted by the infrared illuminator
Many have worried that visible and disturbing light is emitted in the dark, but Apple makes it clear on its site that it is an "invisible infrared light". Finally, an infrared camera scans the point network generated by the projector to create an image and send it to the secure enclosure of the A11 Bionic processor where initial information about the owner's face is stored.
There, the operation looks much like what Apple already did with Touch ID. The "Secure Enclave Coprocessor", as described by Apple in iOS Security Documentation (PDF), uses an encrypted memory in which is stored a mathematical representation of the fingerprint (or face for 'iPhone X). For Touch ID, the image of the fingerprint sent to the secured enclave is then temporarily stored in this encrypted memory the time to be vectorized. It is then immediately erased. The same is true for Face ID.
The Secure Enclave of Apple always inviolable
This mapping is in turn encrypted in a format that can only be read by the Secure Enclave. The latter then compares this model with the original one. If it matches, a green light is then given to the system to unlock the screen. This partial schema does not allow Apple to reconstruct the user's fingerprint. The manufacturer responds to all those who are afraid that their biometric data can be stolen and used without their knowledge.
The advantage of this enclave is its complete isolation from the rest of the system. If the main processor can send the information to the sensor (fingerprint or TrueDepth), it can not read it because it is encrypted and authenticated with a single session key. Apple does not know this key at all and therefore does not have access to any personal data of the user. This information remains in the Secure Enclave and is never sent to Apple's servers for storage. This means that no one can intercept or steal them. If a flaw appeared on Face ID - some are already working on it - it would take physical access to the iPhone X.
Fast through neural calculus
For Face ID, the system goes even further in complexity because the mapping is designed by the new two-core neural computing unit included in the A11 Bionic chip. It can handle more than 600 billion transactions per second. Thanks to "machine learning" - the model was trained by Apple using ultra-realistic masks