Normally is PIN a simple four-digit code ...
Uma boa pergunta, eu pensei o mesmo, mas está errado!
Por favor, dê uma olhada em este artigo :
PIN can be complex
The Passport PIN is subject to the same set of IT management policies as a password, such as complexity, length, expiration, and history. Although we generally think of a PIN as a simple four-digit code, administrators can set policies for managed devices to require a PIN complexity similar to a password. You can require or block: special characters, uppercase characters, lowercase characters, and digits.
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Something like t758A! could be an account password or a complex Passport PIN.
Outros pontos importantes:
PIN is tied to the device
One important difference between a password and a Passport PIN is that the PIN is tied to the specific device on which it was set up.
PIN is local to the device
PIN is backed by hardware