Indistinguishable from random (IND)
 Indistinguishable from random or IND is often referenced in cryptography text.
                    See inside for a practical description!
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Indistinguishable from random (IND)
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2 min read

/[jacobi: angel]---------------------------------------------------------------\
| A cryptographically-suitable key is a sequence of bits that are              |
| indistinguishable from random. In academic literature, it is typically       |
| contracted to IND. Others may say that it is "uniformly random" as it was    |
| selected from a uniform distribution of possible configurations.             |
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/[jacobi: bullshit]------------------------------------------------------------\
| If there is a bias in which states are selected, then it is not uniformly    |
| random. Likewise, if there is a bias when it is encoded to binary, then it   |
| is not uniformly random in binary.                                           |
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/[jacobi: hooray]--------------------------------------------------------------\
| In practical terms an IND bit string cannot be meaningfully analyzed. It is  |
| also impractical to guess or brute force when it is sufficiently long.       |
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/[jacobi: dizzy]---------------------------------------------------------------\
| You may see names like AES-128 or SHA-256 and wonder what that's about. The  |
| names refer to how many bits there are in their configuration or design.     |
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/[jacobi: hmm]-----------------------------------------------------------------\
| Asymmetric keys and asymmetric computations have distinctive patterns, which |
| makes them unsuitable for use in symmetric cryptography like AES-256. See    |
| Why some cryptographic keys are much smaller than others [L1] (archived [L2] |
| ) by CloudFlare. A distinctive pattern makes it not IND!                     |
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Indistinguishable from random (IND):
  It is computationally impractical to determine if an indistinguishable from
  random string was truly random or generated through a computational process.

 [L1]: https://blog.cloudflare.com/why-are-some-keys-small/
 [L2]: https://archive.vn/jhjMm