How secure is 256 bit security?

How hard is it to find a 256-bit hash just by guessing and checking?
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Several people have commented about how 2^256 would be the maximum number of attempts, not the average. This depends on the thing being attempted. If it’s guessing a private key, you are correct, but for something like guessing which input to a hash function gives the desired output (as in bitcoin mining, for example), which is the kind of thing I had in mind here, 2^256 would indeed be the average number of attempts needed, at least for a true cryptographic hash function. Think of rolling a die until you get a 6, how many rolls do you need to make, on average?

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30 gedachten over “How secure is 256 bit security?”

  1. This channel has now surpassed 2²² subscribers and is racing towards 2²³ subs.

  2. So that's what the supercomputer in hitchhikers guide to the galaxy was really about. They wanted to crack a hash. And got… 42.

  3. For the average genius out there: 256 bit being secure, does not mean <your-name>1234 is a good password.

  4. Dilip kumar yadav bhagpur paryagraj upesior ❤up

  5. Nice mind blowing video. Loved it. A followup that would be neat is if quantum computing advancements in processing power was projected out 10 years what would that look like in terms of quantum computers coming near this problem mathematically.

  6. Now imagine instead of having a gpu machine, you have a 240Qbit Quantum Computer.
    Think again.

  7. Another statement that explains the size of 2²⁵⁶…

    $2²⁵⁶ per millennium is enough to make everyone on Earth (distributed) an unvigintillionaire in ~0.27 seconds, and 1 unvigintillion is 10⁶⁶, which is typed/written out as 1,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000.

  8. The funny thing is, 128 bits is already a kilogoogle for multiple times the age of the universe. We still decided to push to 256 bit… Just in case.
    Basically, you only need 256 bit security if you think your security will need to stand up to the combined technological might of a large nation state. Say, for example, nuckear codes.
    But… Is it really good enough to secure my taco delivery order? Rofl.

  9. hello I have a question my seed password is 56 letters long each letter is 8 bits so 8 for 56 and 448 bits right I can't understand can you explain me better thanks everyone

  10. Summary: in theory, if you use SHA-256 to encrypt a file and then you upload it to G Drive… they should need to multiply by billions their hashpower to decrypt it

    PS: pls upload a vid about segwit and its effect on bitcoin security. I heard it removes digital signatures or something

  11. 3 blue 1 brown always comes In clutch with the visualizations. This reminds of combinatorial explosion, and how often it comes up in real world problems, it would be interesting to see you make a video going into depth on this topic.

  12. Well, I'm running Shor's Algorithm on my personal Quantum Computer.
    You keep going with your (4 Billion)^8 seconds.

  13. As of Jan 9th 2024 the total Bitcoin mining hash rate is 533 billion billion hashes per second.

  14. It depends on how long your input is. for example if you have decrypted input like 4394 its like a second to encrypt it with brute force. Thats why you should use 8 length passwords At least 1 uppercase character and a number or symbol. Then you will be dead by that time by you try to encrypt it). But still possible

  15. As of watching, you not only have surpassed 2^18 but also 2^22

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