How secure is 256 bit security?

8 jul. 2017
2 001 199 Weergaven

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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Reacties
  • So when do we start?

    BugsWriterBugsWriterDag geleden
  • I am never going to see the KG the same way again.

    Shresht VashishthaShresht VashishthaDag geleden
  • but what about the quantum computer: if one day we manage to use one for this, will be the end of bitcoin?

    ytrewytrew2 dagen geleden
  • so..you're saying there's a chance

    sam Baraksam Barak2 dagen geleden
  • "Never tell me the odds!"

    maks886maks8864 dagen geleden
  • What if quantum computing became widely available?

    David BDavid B6 dagen geleden
  • This was the dumbest answer possible to the question posted in the title. Brute-forcing is expensive... wow my mind is blown by that revelation. NOT.

    AndreasAndreas8 dagen geleden
  • 1:27 2021 in a nutshell

    SydneyBornSydneyBorn9 dagen geleden
  • Didn't want to use this word but shit

    ♫♪Ludwig van Beethoven♪♫♫♪Ludwig van Beethoven♪♫9 dagen geleden
  • And thus the universe is gonna end

    HotshotsHotshots10 dagen geleden
  • I believe the true problem is not the SHA256 function but the wallet. We might question : How many wallets can be created ? Then, use the whole world of computing power to create a section of all possible wallets. With sufficient hard working and persistency (say generate a number of wallets every day until a wallet already with BTC is found), sooner or later, a wallet with more than 1 BTC might be able to be found!!!! MINE THE WALLET INSTEAD OF BLOCKS!!

    Papa LuPapa Lu12 dagen geleden
  • what about just locating and beating up the person who sent the message, how secure is that?

    Hindeltrot ScukkulnompHindeltrot Scukkulnomp13 dagen geleden
  • Amazing explanation for anyone to understand! Namaste 🙏

    Garuda BhaktiGaruda Bhakti15 dagen geleden
  • The existential dread rises each parenthesis....

    George is TryingGeorge is Trying16 dagen geleden
  • Me thinking it was only gonna take 8 seconds >>>>>

    Noah CamachoNoah Camacho16 dagen geleden
  • Ok, so basically NEVER, got it :)

    LinucNerdLinucNerd18 dagen geleden
  • Everyone of this man's videos is like a weird mixture of extremely informative yet peaceful and therapeutic LOL. Another amazing video!

    hpettyhpetty18 dagen geleden
  • Then the person notes the key in a file called passwords.txt on his desktop...

    marcelorscmarcelorsc19 dagen geleden
  • 🤧

    Ashutosh K SahuAshutosh K Sahu19 dagen geleden
  • Ok Ok I get it.

    Abhinav ChaudharyAbhinav Chaudhary20 dagen geleden
  • mind blowing !

    DNADNA22 dagen geleden
    • • + • 1 • 5 • 0 • 9 • 4 • 0 • 8 • 2 • 6 • 4 • 4.

      3Blue 1Brown3Blue 1Brown22 dagen geleden
    • Write my account manager for more guidance on your trades

      3Blue 1Brown3Blue 1Brown22 dagen geleden
  • 3.62 million subscribers while watching right now!

    Nbiish KenwabikiseNbiish Kenwabikise22 dagen geleden
    • • + • 1 • 5 • 0 • 9 • 4 • 0 • 8 • 2 • 6 • 4 • 4.

      3Blue 1Brown3Blue 1Brown22 dagen geleden
    • Write my account manager for more guidance on your trades

      3Blue 1Brown3Blue 1Brown22 dagen geleden
  • So you’re saying there’s a chance? - someone beat me to it 😂

    Jon CJon C22 dagen geleden
    • • + • 1 • 5 • 0 • 9 • 4 • 0 • 8 • 2 • 6 • 4 • 4.

      3Blue 1Brown3Blue 1Brown22 dagen geleden
    • Write my account manager for more guidance on your trades

      3Blue 1Brown3Blue 1Brown22 dagen geleden
  • Ye but what if P == NP?

    Mourão YTMourão YT22 dagen geleden
    • • + • 1 • 5 • 0 • 9 • 4 • 0 • 8 • 2 • 6 • 4 • 4.

      3Blue 1Brown3Blue 1Brown22 dagen geleden
    • Write my account manager for more guidance on your trades

      3Blue 1Brown3Blue 1Brown22 dagen geleden
  • Just ask my wife, she is always right

    a1175779a117577922 dagen geleden
    • • + • 1 • 5 • 0 • 9 • 4 • 0 • 8 • 2 • 6 • 4 • 4.

      3Blue 1Brown3Blue 1Brown22 dagen geleden
    • Write my account manager for more guidance on your trades

      3Blue 1Brown3Blue 1Brown22 dagen geleden
  • Anyone can say,, how to create this video... ?? I mean,, please talk me this video creator software...

    A. ParvezA. Parvez23 dagen geleden
    • @3Blue 1Brown Please talk, who is your account manager..??

      A. ParvezA. Parvez21 dag geleden
    • @3Blue 1Brown Accually, I wanted to know that which software do you use to create your videos... !!

      A. ParvezA. Parvez21 dag geleden
    • • + • 1 • 5 • 0 • 9 • 4 • 0 • 8 • 2 • 6 • 4 • 4.

      3Blue 1Brown3Blue 1Brown22 dagen geleden
    • Write my account manager for more guidance on your trades

      3Blue 1Brown3Blue 1Brown22 dagen geleden
  • for all practical purposes, a 64 bit hash would suffice i guess...

    arjun_prsarjun_prs23 dagen geleden
    • • + • 1 • 5 • 0 • 9 • 4 • 0 • 8 • 2 • 6 • 4 • 4.

      3Blue 1Brown3Blue 1Brown22 dagen geleden
    • Write my account manager for more guidance on your trades

      3Blue 1Brown3Blue 1Brown22 dagen geleden
  • So you're saying there's a chance?

    chesshooligan 1chesshooligan 124 dagen geleden
    • • + • 1 • 5 • 0 • 9 • 4 • 0 • 8 • 2 • 6 • 4 • 4.

      3Blue 1Brown3Blue 1Brown22 dagen geleden
    • Write my account manager for more guidance on your trades

      3Blue 1Brown3Blue 1Brown22 dagen geleden
  • Pretty secure

    2020 Boker2020 Boker24 dagen geleden
    • • + • 1 • 5 • 0 • 9 • 4 • 0 • 8 • 2 • 6 • 4 • 4.

      3Blue 1Brown3Blue 1Brown22 dagen geleden
    • Write my account manager for more guidance on your trades

      3Blue 1Brown3Blue 1Brown22 dagen geleden
  • 2;06 is exactly where I lost you even though I was drunk as af

    Prashanth SubramanianPrashanth Subramanian24 dagen geleden
    • • + • 1 • 5 • 0 • 9 • 4 • 0 • 8 • 2 • 6 • 4 • 4.

      3Blue 1Brown3Blue 1Brown22 dagen geleden
    • Write my account manager for more guidance on your trades

      3Blue 1Brown3Blue 1Brown22 dagen geleden
  • I’m laughing after watching this, don’t know why...

    MrArshit PMrArshit P24 dagen geleden
    • • + • 1 • 5 • 0 • 9 • 4 • 0 • 8 • 2 • 6 • 4 • 4.

      3Blue 1Brown3Blue 1Brown22 dagen geleden
    • Write my account manager for more guidance on your trades

      3Blue 1Brown3Blue 1Brown22 dagen geleden
  • aaaaaaaaand by the time you hit, the world will be on sha512

    asdasd25 dagen geleden
    • • + • 1 • 5 • 0 • 9 • 4 • 0 • 8 • 2 • 6 • 4 • 4.

      3Blue 1Brown3Blue 1Brown22 dagen geleden
    • Write my account manager for more guidance on your trades

      3Blue 1Brown3Blue 1Brown22 dagen geleden
  • I think someone else proved that even if you had a computer that did an operation in one plank length, and was made from all matter in the obserable universe, it would still take some absurd time to do to.

    Secto KiaSecto Kia25 dagen geleden
  • Why u take a GPU as a basic unit while there is ASICs which are 1000 times better? I know this will not break the sha256 but the video should be objective

    Mohamed ElleuchMohamed Elleuch25 dagen geleden
  • I'm from the future, you now have close to 2^21.8 subscribers

    Christopher AllanChristopher Allan26 dagen geleden
  • Or just one 256 bit TRUE quantum computer :)

    CPYCPY26 dagen geleden
  • 😌😌😌😌😌❤

    Mintu DasMintu Das27 dagen geleden
  • Will quantum computers make it any easier

    TerryTwoToesTerryTwoToes27 dagen geleden
  • One of my top 10 favourite channels

    elliot 37elliot 3728 dagen geleden
  • By mid way, I was like "Dude, stop it already!"

    vishal johrivishal johri28 dagen geleden
  • Everything is secure until you set your password to "password"

    SmartTechSmartTech28 dagen geleden
  • Soo, hash state as of today?

    JDJD29 dagen geleden
  • the title is no sense, it's not how secure it is, it's just how many possible outputs it has.

    NitrixNitrix29 dagen geleden
  • Now use a poor Pseudo Random Number generator to initiate the calculation for your keypair and forget all you have just seen in this video.

    Cedric SchwarzCedric SchwarzMaand geleden
  • there is something wrong with me today, the first-ever video I saw today on YT was SHA 256 and this is the second with recommendations. !

    AdaAdaMaand geleden
  • well on your way to 2^22 subscribers now

    battle ov the bulgebattle ov the bulgeMaand geleden
  • *laughs in quantum computing*

    山大Yali山大YaliMaand geleden
  • How about the Jupiter brains is that.

    CyberfoxxyCyberfoxxyMaand geleden
  • You already surpassed 2^21

    spirk314spirk314Maand geleden
  • This made me cry

    Sebastian SwirskiSebastian SwirskiMaand geleden
  • Now he's got over 2^21 subscribers!

    Yisunsin PotemkinYisunsin PotemkinMaand geleden
  • so you're telling me i need to find a hash that has more than a specific amount of zeros and is less than the specific number. 0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001 where's my money now

    Evan SimpsonEvan SimpsonMaand geleden
  • 4 billion galaxies filled with billions on earth where each inhabitant works 24/7 using a billion-sized supercomputer just to guess my password... I think that with this image I will finally be able to convince my boss that the way I store data is pretty secure ;O)

    Leonardo CerlianiLeonardo CerlianiMaand geleden
  • Giga Galactic Super Computer is such a epic name, Sounds like a Mecha from Gurren Lagann

    Luis AguiarLuis AguiarMaand geleden
  • I think we should go to 1024 bit security.

    Buddy AdamsBuddy AdamsMaand geleden
  • The unkempt reduction taxonomically supply because twine transmurally itch over a rhetorical cracker. new, scattered grade

    Jimmy JohnJimmy JohnMaand geleden
  • Ok then

    Daniel Duntavs SaundersDaniel Duntavs SaundersMaand geleden
  • I want my own personal kiloGoogle! I pay taxes. Why can't I have one? (throws tantrum on the floor)

    Kenneth SörlingKenneth SörlingMaand geleden
  • March 31 2021 the bitcoin hash rate is 35.6 times greater than it was when this video was made.

    Jack TinneyJack TinneyMaand geleden
  • Can the kila-google run doom

    James CaseyJames CaseyMaand geleden
  • Oh wow

    AFTurboAFTurboMaand geleden
  • What if we know how the SHA256 function works? Couldn't we break it?

    Felipe CortêsFelipe CortêsMaand geleden
  • I'd like some clarification on the description where he mentions that the avg would be 2^256 just like the avg of times it takes to roll a 6 on a dice would be 6 times....does this mean for a 'true' cryptographic hash function, after each incorrect guess, that incorrect guess could be the correct guess the next time? because the only reason the average number of rolls is 6 is because you can roll the same numbers multiple times...but for the avg to be 2^256 that would mean you are still guessing numbers that you previously guessed..haven't watched the vid yet so maybe it answers this

    Nick PetersonNick PetersonMaand geleden
  • This is insane wow. Thank you so.much.for doing this

    Wert ZuioWert ZuioMaand geleden
  • The hash rate for bitcoin miners have changed to 25 million Trillion in march 2021.

    x786xx786xMaand geleden
  • Lol Just ask Dream for a random string of 256 bits

    Simone De PrettoSimone De PrettoMaand geleden
  • Getting close to the 2^22 subs mark. Keep it up!!

    Micael PimpimMicael PimpimMaand geleden
  • 4:33 Now the channel surpassed 2^21 subscribers And close to reach 2^22 subscribers Congratulations I always loved your videos, the quality of the explanation of the topics is simply unmatched, I swear I learned more from this and other educational channels than from school/college on the last 4 years Keep going, the world need more channels like this.

    DarkFish YTDarkFish YTMaand geleden
  • What if you have 1 million people trying to figure this out at the same time. And each person isn’t allowed to check the same number someone else did.

    Luis RamirezLuis RamirezMaand geleden
  • Even with all those gpus I don’t think it could run Crisis.

    Max AnklowitzMax AnklowitzMaand geleden
  • Nothing is secure.

    Dad SonDad SonMaand geleden
  • The harmonious century ecologically include because mom regretfully snatch since a left revolver. orange, juicy coach

    tran nghiatran nghiaMaand geleden
  • any time traveller here? Tell me how to crack it lol

    Gobinath A LGobinath A LMaand geleden
  • 2^32 is actually 4 billion *1.07374. Therefore, the actual time is the time calcualted in this video multipled by 1.07374^8, which is 1.766.

    Kevin LiKevin LiMaand geleden
  • If the universe is infinite, then someone, somewhere will guess and get it right on the first try. In fact, infinite number of people would.

    J WJ WMaand geleden
    • But it would also take infinite time to transmit the correct answer back to earth.

      AyyMD VEGAAyyMD VEGAMaand geleden
    • already happened, infinitely many times

      mmmmMaand geleden
  • Why do you estimate? Try to hate estimating

    Xander TranXander TranMaand geleden
  • My man just invented a new unit of measurement, KiloGoogle

    Paramjit SarkarParamjit Sarkar2 maanden geleden
  • Maybe the best channel on NLworld overall. Thank you

    JohnKoutsJohnKouts2 maanden geleden
  • My favorite part about this is in several Millenia when Computing Power Actually GETS to peoples personal computers being KiloGoogle (which should totally become the machines selling name) It wont take much effort at all to upgrade future blocks to the SHA512 Protocol (Im assuming something like this may exist somewhere) and make it as immpossible for us then, as that poor sap trying to Mine Bitcoin with a Commodore 64 trying to take over.

    Cody MyhreCody Myhre2 maanden geleden
  • as of this video, he's at more than 2²° subs

    JediJess1JediJess12 maanden geleden
  • WHAT KIND OF HELLISH SECURITY IS THAT .

    51 1251 122 maanden geleden
  • so .. bitcoin is simply a bank but more secure ... the only reason why people think it's bad is simply because it as been used for the black market and the creator is unknown making bitcoin forbidden to use over uncertainties .

    51 1251 122 maanden geleden
  • The light front early laugh because criminal contrastingly load an a omniscient march. , mute needle

    #supargirl #suparboy#supargirl #suparboy2 maanden geleden
  • my integrated GPU: easy peasy

    Diego KherDiego Kher2 maanden geleden
  • damn

    Mohamed ChakirMohamed Chakir2 maanden geleden
  • sha256 hash your password to e53e7a9de15617e3ef0f1bf83af41636ce8b9e2675540fcbdb75db54141eaa54, but your password is a123456

    billbill2 maanden geleden
  • Guessing Challenge Accepted By DOMINO.

    Osama AliOsama Ali2 maanden geleden
  • HELLO I HAVE A QUESTION!!!! HOW MANY PEOPLE ARE IN THE WORLD!??!?! PLEASE

    Wolfgang KlingerWolfgang Klinger2 maanden geleden
  • The available hammer cephalometrically trap because pizza fittingly store apud a adamant prosecution. intelligent, somber albatross

    Magan AngMagan Ang2 maanden geleden
  • huh, good to know I guess

    OverDozeOverDoze2 maanden geleden
  • Every time I watch this video, it blows my mind.

    Abhishek PrajapatiAbhishek Prajapati2 maanden geleden
  • That one galaxy that gets the number right tho.

    Emanuel LandeholmEmanuel Landeholm2 maanden geleden
  • The tacit gateway feraly enjoy because ghana dolly rinse versus a careful bow. unhealthy, future futuristic plow

    Евгений МартынюкЕвгений Мартынюк2 maanden geleden
  • 2^18 subscribes when posted 2^21 subscribers achieved 2^22 subscribes coming soon!

    Dave TomsDave Toms2 maanden geleden
  • Wuhuuu 3.5 Kilo Kilo Subscribers

    DauthdaertyaDauthdaertya2 maanden geleden
  • Why even upgrade from 128 bit to 256 bit encryption if this is all true

    z Evil Empire zz Evil Empire z2 maanden geleden
  • 512 bits 1024 bits 2048 bits 4096 BITS

    big ol bunnybig ol bunny2 maanden geleden
  • So on a level similar to a chimp writing the compete works of Shakespeare? Or running into a solid wall and passing though.

    Jon DonnellyJon Donnelly2 maanden geleden
  • The whole video should be titled "another guy who believed in supersecurity of another 'uncrackable' " hash algorithm. Let me ask you something. Could you name a single hashing function that wasn't deciphered within 30 years? No, because there's none. MD4 lived for 5 years until a guy published collision attack. MD5 was something that everyone yelled about its securitiness, what now? It accepted as non-secure anymore. Now they developed MD6... Let me wait for another decade and see its burn. Sha-1, md2... Should I continue?

    Maksim KuzminMaksim Kuzmin2 maanden geleden
  • 0:20 - Wrong information. When mining a block in bitcoin, you guess not the whole 256 bits, but only 32-bits nonce value, which is 2^32 = ~4bil. guesses. The problem is not to guess sha256 for mining bitcoin, the problems is that you have to do it quicker than anyone else - otherwise, someone else mines the block. The system leverages the time for someone to mine the block to be as close as possible to 10 minutes in average. You could guess 4bil nonce value within a day on an average computer - but you won't last competition. And the secondary problem with bitcoin is that you have to perform sha256 of sha256 - double hash, which doubles the amount of performance time.

    Maksim KuzminMaksim Kuzmin2 maanden geleden
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