trying to brute force a specific length of ciphered pad, how do we measure the total number of possible encryptions in One Time Pad

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    $\begingroup$ Brute force the One Time Pad?! Have a nice snipe hunt. Hint: if the pad has length $n$ bits, how many values can it take? $\endgroup$
    – fgrieu
    Nov 20, 2015 at 18:28
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    $\begingroup$ I can do it in 3 steps. 1) Find the person who encrypted the message. 2) Beat them with a rubber hose until they tell you the key. 3) Profit. $\endgroup$
    – mikeazo
    Nov 20, 2015 at 18:41
  • $\begingroup$ @mikeazo I doubt they'll remember the key. $\endgroup$
    – Aleph
    Nov 20, 2015 at 18:43
  • $\begingroup$ @Aleph, but they will tell you where the key is and / or how to recover it! $\endgroup$
    – SEJPM
    Nov 20, 2015 at 18:52
  • $\begingroup$ @AKC The probability of an attack failure scales proportional to the length of ciphertext. See, without human error like (eg) “key reuse”, you’re facing so called “perfect secrecy” – you can’t gain any usable information about the plaintext. Assuming you don’t know any plaintext either, it’s practically a waste of time unless you’re really, really lucky guessing parts of the key… which has near-to-perfect randomness if OTP has been applied correctly. (PS: Always do some research before asking; including searching Crypto.SE. We have 130+ one-time-pad related questions with answers!) $\endgroup$
    – e-sushi
    Nov 20, 2015 at 19:04