It's sickening to hear all this hocus-pocus about Windows 10 is spying.
Please explain how data is sent to Microsoft?
Windows Hello Privacy:
Windows Hello and privacy: FAQ - Microsoft Windows
What data is used to identify me and how is that data stored?
During set-up, Windows takes the data captured from the face or iris sensor or fingerprint reader and creates a representation that it encrypts and stores on your device. (This isn't an image; it's more like a graph.) The representation of you stays on your device. Windows never stores pictures or images of your face, iris or fingerprint on your device or anywhere else.
Does any of the data that Windows Hello collects ever leave my device, and if so, how is it transmitted?
Your identification data – the representation of your face, iris or fingerprint that's created when you enrol – never leaves your device. To help us keep things working properly, to help detect and prevent fraud, and to continue to make improvements, Microsoft collects usage data such as which method you used to sign in (face, iris, fingerprint or PIN), the number of times you signed in, and whether or not each sign-in was successful. This data is stripped of any information that could be used to specifically identify you, and it's encrypted before it's transmitted to Microsoft.
Can you recreate my face, iris or fingerprint from the data that Windows Hello collects?
No. The identification data collected to sign you in isn't an actual image. It's a representation based on the unique qualities of your face, fingerprint or iris (more like a graph than an image). This data can't be used to recreate an image of your face, fingerprint or iris.
Do third parties have access to my Windows Hello identification data?
No, third parties don’t have access to your Windows Hello identification data.
Similar with Touch ID Security: About Touch ID security on iPhone and iPad - Apple Support
Secure Enclave
Touch ID doesn't store any images of your fingerprint. It stores only a mathematical representation of your fingerprint. It isn't possible for someone to reverse engineer your actual fingerprint image from this mathematical representation. The chip in your device also includes an advanced security architecture called the Secure Enclave which was developed to protect passcode and fingerprint data. Fingerprint data is encrypted and protected with a key available only to the Secure Enclave. Fingerprint data is used only by the Secure Enclave to verify that your fingerprint matches the enrolled fingerprint data. The Secure Enclave is walled off from the rest of the chip and the rest of iOS. Therefore, iOS and other apps never access your fingerprint data, it's never stored on Apple servers, and it's never backed up to iCloud or anywhere else. Only Touch ID uses it, and it can't be used to match against other fingerprint databases.
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