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A one-time pass is still uncrackable.

Take your secret. Write it on a piece of grid paper. Fill EVERY FIELD on another piece of grid paper with random data. Transform every character on the first piece of paper based on the corresponding characters on the second piece of paper and write the result on a third piece of grid paper. Then burn the first piece of paper.

It's not possible to read the 3rd piece of paper without the 2nd now. You also obscure the length by filling the second piece of paper with data.




One-time pads are extremely impractical and error-prone. You need:

1. A secret key as long as the plaintext.

2. A consistent source of true randomness and a way of sampling it such that your secret key is truly random.

3. To never reuse a key once it's been used once.

Imagine the ramifications of retrofitting servers to use one-time pads for TLS. Moreover, essentially everything we take for granted in cryptography relies on constructions which use pseudorandom permutations and generators. Even if we resolved all these problems and forged ahead in a brave new world using stream cipher-like constructions based on one-time pads, we'd still have to rethink all of public-key cryptography.

This impracticality is one of the major reasons we moved on from information theoretic security to complexity theoretic security by the mid 20th century.


For what it's worth, quantum computers might give a provably correct source of 2 (random numbers).

The version I saw (requires 2 quantum devices): http://www.henryyuen.net/fall2018/scribe2.pdf

New paper that claims to do it with only one quantum device: https://arxiv.org/pdf/1804.00640.pdf


Sure of course its incomprehensibly impractical.




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