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Win $200,000 In RSA's Factoring Challenge

BetaRelease writes: "All ye with excess CPU cycles to spare. Here's a chance to win as much as $200,000. Join RSA's Factoring Challenge." That means you can get $10,000 for figuring out the factors for this laughably easy, completely trivial number, or twenty times that if you can figure out a slightly nastier one. While it would probably take more horsepower to win any of the prizes than the prize money could pay for, admit it would be cool to trade a 98-digit number for a few years' salary.

152 comments

  1. Re:Clustering.. by Anonymous Coward · · Score: 1
    I think you need a Beowulf cluster to crack one of these.

    Fucking hell, that was almost relevant. Unlike this.

  2. Of course by Anonymous Coward · · Score: 1

    If you *do* crack it, you will be sued and go to jail under the DMCA

  3. Re:Method of doing this? karma whore ... by Anonymous Coward · · Score: 1
    Linux is an operating system with math emulation, operating on signed integers, rational numbers, and floating point numbers. It has a rich set of functions, and the functions have a regular interface
    home page for Linux

    Please mod me up too, I posted a link !!!!

  4. Re:Imagine if you will.. by Anonymous Coward · · Score: 1

    More or less yes. But (if I understood the way america count):

    Thousand = 10^3
    Million = 10^6
    Billion = 10^9
    Trillion = 10^12

    The first (the 'easy') number is approximately 10^174. Its factors are in the order of 10^87. In that range, there is a prime number every few hundred of numbers, so your chances are in the 10^84

    You have one chance in a trillion of trillion of trillion of trillion of trillion of trillion to find the good number.

    So, basically, the contest is more about finding new ways to factorize big numbers. Not easy ways, but slighly more practical ones.

    Cheers,

    --fred

  5. the answer is..... by Anonymous Coward · · Score: 1

    ok. hold on, just let me click ok..... DAMN IT!! windows crashed... i guess i have to start over.

  6. So Long and Thanx for all the Fish.... by Anonymous Coward · · Score: 1

    I just showed the RSA numbers to my dolphin and he just laughed.... eeeeee eee eee

  7. Re:Translation by Anonymous Coward · · Score: 1

    They want to see if it can be done efficiently, because they made the bet that it can't. One 617-digit number is only 10^-617 of the whole range of 617-digit numbers, it's almost nothing.

  8. Stupid joke by Anonymous Coward · · Score: 2

    I have a nice factorisation of the 617
    digits one, but it is too big to fit in this post...

    1. Re:Stupid joke by Kraft · · Score: 3

      LOL.... no this is a cool joke!! I presume you are referring to Fermat's comment in the margin on his notebook about having the solution to his own theorem.

      I just read Fermat's Last Theorem by Simon Singh a month ago and I loved it.

      -Kraft

      --

      -Kraft
      Live and let live
  9. Stupid windows calculator by Anonymous Coward · · Score: 2

    Cut and paste the big number into windows calculator and watch the number pad go nuts.

  10. ok... by Anonymous Coward · · Score: 4

    i've decided i'm going to spend any free time i have at work on this project.

    i've just requisitioned 8,000 reams of paper and 5000 number 2 pencils. wish me luck.

    1. Re:ok... by cmclean · · Score: 1
      i've just requisitioned 8,000 reams of paper and 5000 number 2 pencils

      OBPYTHON:
      Pencils! Cor bilmey the young today don't know they're born! In my day we had to use burnt sticks! And we didn't have the decimal system! Ooooh no we had to get by with roman numerals! Which we had to invent! etc. etc.

      cmclean

      --
      "Any similarity between the hooting of a million eager monkeys and Slashdot is purely coincidental." -THEFLASHMAN
    2. Re:ok... by cyberformer · · Score: 1

      Be careful. Your employer might fire you, then two years later prosecute and sue you for improper use of resources. If a second of CPU time is worth 59 cents, a number 2 pencil must be worth several thousand dollars.

    3. Re:ok... by pinkfluffy · · Score: 2

      I bet they all turn out to be primes :)

  11. I'VE GOT IT! by Have+Blue · · Score: 2

    All the numbers are divisible by 1!!! Gimme the cash!

  12. Re:Wonder if Distributed.net will pick this up? by bluGill · · Score: 2

    From the FAQ:

    As shown, to factor a 760-bit number in one year would require 215,000 Pentium-class machines, each with 4 Gigabytes of physical RAM. These are estimates based on today's best factoring technology.

    I don't think distributed.net will make much progress based on current algorythms. Most people just do'nt have that much memory to donate to the cause. Might be time to invest in memory makers if you think they will buy it.

  13. Re:Just to get us started ... by bluGill · · Score: 2

    Accually for 5 you only need to check for a last didget of 5. If the last didget was 0 it would be even, and we already have determined that it isn't even. Further we know that there are exactly TWO primes involved, so if it ended in 0 the only possibility is 2 and 5, which means the number is 10.

    I don't know how to help you with 7, but I did just save you a millisecond with 5.

  14. Re:Imagine if you will.. by bluGill · · Score: 3

    Right. Pick two (presumably large, though there is no reason it has it couldn't be 1 very large and one laughably small prime number) prime numbers. Multiplu them togather. If the answer is that number, you have the solution.

    The only problem is it is easy (as in I once did this when I was taking a class, but since have forgotten how) to prove that there are a lot of prime numbers to chose from. We also know of good ways to find out if a number is prime, but no good way to find the factors if it isn't.

    Still, have fun. It isn't that hard to find two prime numbers with a paper an pencil. Of course arthmitic mistakes are likely, and it takes a lot of time)

  15. Brute force only way to do this? by DG · · Score: 1

    Just doodling on the back of a napkin, trying to figure out the best way to tackle this one.

    The obvious way is pure Brute Force: Iterate between 2 and n, where n is the number. If the current iteration i divides into n, j times (with no remainder), remember the factors i and j, and then recursively repeat with i and j as values for n.

    Continue until all values of n are non-divisible (prime)

    Anybody have a better algorithm?

    --
    Want to learn about race cars? Read my Book
    1. Re:Brute force only way to do this? by forii · · Score: 1

      Actually, there are many better ways. (First of all, you only have to iterate from 2 to sqrt(n) in your algorithm :) ). The current best way is a Number Field Sieve, at least for large numbers. Search around to see what it is.
      The second volume of Knuth's Art of Computer Programming series has a good discussion of different factoring algorithms, and their applicability at different times.

    2. Re:Brute force only way to do this? by forii · · Score: 1

      Ah, all you have to do is factor that 704 bit number and there you go.

      Or, alternatively, you could go factor the 704 bit number in the RSA challenge, take the $30,000, go buy Knuth a beer and just ask him what the answer is. :)

    3. Re:Brute force only way to do this? by alexjohns · · Score: 2

      Hmmm, I have the original edition. I don't see a question 47. Question 16, the last one, is the only one rated 50 that I see: 'Are there infinitely many Mersenne primes?'

      Intuitively, I would say yes. I can't prove it. I don't know that anyone has.

      Knuth does say, in the 'Notes on the Exercises', that a 50 is a research problem that hasn't been solved yet. As his example he uses Fermat's last theorem. Of course, the book is copyright 1969. Don't know if he's corrected that in the latest edition. No reason to buy the new one, I'm not finished with this one yet!
      --
      Alex Johns

    4. Re:Brute force only way to do this? by dlapine · · Score: 1
      Wouldn't it be quicker to stop once n is greater than or equal to the square root of the number to be factored?

      You already have the "j", which will cover all numbers above the square root.

      This is similar to brute force prime finding...

      Also, why recurse? At this number of digits, the number of recursions is gonna give your system a headache. Just do a linear scan from 2 to square root of n equals x

      --
      The Internet has no garbage collection
    5. Re:Brute force only way to do this? by Lozzer · · Score: 2

      Wouldn't it be quicker to stop once n is greater than or equal to the square root of the number to be factored?

      Only in an abstract kind of sense. Given that the numbers are composite (and the RSA could be lying here) - the alogrithm will be sure to have finished before your optimization comes into play. Hence the calculation as to what the square root was will slightly slow down the overall run time.

      --
      Special Relativity: The person in the other queue thinks yours is moving faster.
    6. Re:Brute force only way to do this? by 3am · · Score: 1

      okay, hopelessly math/cs dork question, but have you ever heard of anyone having the answer for question 47 of section 4.5.4 (book 2)? seems doubtful, as it's rated a '50'

      i was more interested in addition chains, but that one piqued my curiosity.

      --

      A: None. The Universe spins the bulb, and the Zen master merely stays out of the way.
    7. Re:Brute force only way to do this? by 3am · · Score: 1

      ah, i have the updated and revised, but here goes:

      '47. [M50] A certain literary quotation x = x1*x2, represented in ASCII code, has the enciphered value (x1^3 mod N, x2^3 mod N) =

      (14e97ef5c531d92591b89cdbab48444a04612c01aa29c2a8f a10fa804ef7ac3ce03d7d3667c4d3e132a24a68e6797fe2865 0dc3adf327474b86b0cbd5387a49872ceo12269a59b3e4b3bd 83b74681a78ad7b6d1772a7451b15b025e2aee095a95425901 84cf62f72b2e8e8dd794aef8511f2591e6bc2c8b8a8e48af1f e04ff2fd933e7309205a3418dbb9bb8c6a7665da309531735f e86c741d1261b34cb2668fa34d0c0c28575a2454e3db00e408 ac7)

      in hexadecimal notation, where N is

      17b2353b9595eca69fef80940160c4084286d1255ffe49d114 f2e633f82c88d5224fc4aa6f9104ced2bca810bea76157ffdc 78f9656a0ed9b3f6ccab99001b8b2571f4ebd095925f07f9be e5111e8375dfd71593628ad8d1

      What is x?

      --

      A: None. The Universe spins the bulb, and the Zen master merely stays out of the way.
  16. Answered my own question: see URL by DG · · Score: 2

    http://www.rsasecurity.com/rsalabs/faq/2-3-4.html

    Hmm...

    All the Challenge numbers are the product of two primes, so there's only 2 factors. If we had a list of al the primes of length n, where n is the length of the longest Challenge number, this would be trivial. But since we don't...

    Well, read the FAQ for yourseves. :)

    --
    Want to learn about race cars? Read my Book
    1. Re:Answered my own question: see URL by Y2K+is+bogus · · Score: 2

      (Please excuse the spaces in the numbers, it's to counter the lameness filter).

      You are incorrect about the square root.

      First of all, just look at RSA 130. It's a 130 digit number with 2, 65 digit prime numbers. In fact the 2 factors are:

      45534498646 73597218840 36868972744 08864356301 26320506960 0999044599

      and

      39685999459 59745429016 11261628837 86067576449 11281006483 2555157243

      The product of those 2 numbers is:

      18070820886 87404805951 65616440590 55662781025 16769401349 17012702145 00566625402 44048387341 12759081230 33717818879 66563182013 214880557

      Which has the square root of (approx):

      42509788151 52346540745 26976625052 94703186899 16508643485 6734890373.3

      Which is LESS than one of the factors.

      This means that checking UP TO the square root was not effective in this case.

      The other point is that the big products appear to generally be 2x the number of digits of their factors. This means that to pick your starting point for the factors, you use the square root of the product. Fitting the numbers isn't something you can just easily brute force. In RSA130 the two factors had a difference of:

      58484991871 38517898242 56073439062 27967798521 50395004768 443887356

      That is a lot of comparisons.

    2. Re:Answered my own question: see URL by sachmet · · Score: 1

      Not exactly...

      For n, there is at least one factor that is between 1 and sqrt(n).

      Thus, for 14, factors being 2 and 7, and sqrt(14) being ~3.741657, your statement is false.

      Although, once you know one factor, the other must fall into place.

      As a side note, if you're too lazy to figure out which numbers are prime before trying them, just try all numbers that end in 1,3,7, and 9. After 10, those are the only digits a prime can end in.

    3. Re:Answered my own question: see URL by honcho · · Score: 1

      The prime number theorem approximates the number of primes < 10^617 as approx. 7*10^612

      pi(x) ~ x/(log x - 1) where x = 10^617 and log is the natrual log

      See http://www.utm.edu/research/primes/howmany.shtml#1

    4. Re:Answered my own question: see URL by egomaniac · · Score: 2

      Uhhhh ... no I'm not. One of the factors is guaranteed to be less than or equal to the square root. We're only trying to find that one -- once you've found that number, you've found both of them. The other one is the quotient of the division, and the fact that it is an integer shows you that you've just found the factors. *No shit* one of the numbers will be bigger than the square root -- given that the number will never be a perfect square (since we choose two different primes) this is absolutely guaranteed.

      Did you actually read my message? If you did, please read it again. My whole point was how dumb a brute force algorithm was -- I sincerely hope you didn't think that I was suggesting that taking far longer than the lifespan of the universe to solve the problem was reasonable.

      --
      ZFS: because love is never having to say fsck
    5. Re:Answered my own question: see URL by egomaniac · · Score: 3

      Please define "trivial", 'cause I don't think we're using the same definition of it.

      I don't know how many primes there are below 10^617, but here's a hint: it's a LOT. A lot a lot. I don't know what the ratio of primes to nonprimes if, but let's just assume that 1 in 1 trillion numbers up to that level is prime (and I imagine that's conservative). 1 trillion is 1,000,000,000,000, or 10^12. So that reduces our number of primes down to 10^605. That's still a 605-digit number of them. Say it's only 1 in 100 quadrillion numbers -- still 10^600 primes.

      So in order to solve the problem, you just attempt to divide the big number by each of the primes, and when you get an integral result, you stop. In fact, you only have use primes up to the square root of the number. The square root of 10^600 is 10^300. Assume you have a super-duper fast machine which can divide such an insanely huge number in just, say, 10 clock cycles, and it runs at 10GHz. That's a billion checks per second (10^9) -- really fast, huh?

      So let's figure out how long our super-fast machine would take to crack this code using your method. 10^300 checks, divided by 10^9 checks per second, gives you 10^291 seconds. There are approximately 31,557,600 seconds in a year, or 3.15 * 10^7. 10^291 / (3.15 * 10^7) = 3.17 * 10^283. That's 31.7 million million million million million million million million million million million million million million million million million million million million million million million million million million million million million million million million million million million million million million million million million million million million million million million years.

      I'm glad to know, however, that I can now file this problem away in my "trivial" category.

      --
      ZFS: because love is never having to say fsck
    6. Re:Answered my own question: see URL by Sir+Mix+A+Lot · · Score: 1

      No, he is right about the square root. Unless your search is broken, you should encounter the first prime number, which is less than the square root of the product, before you encounter the one that is above the square root.

      % rm * .o
      rm: .o: No such file or directory
      % ls
      %

      --

      % rm * .o
      rm: .o: No such file or directory
      % ls
      %
      damn
    7. Re:Answered my own question: see URL by einhverfr · · Score: 2

      Generate one recursively... for n, all possible factors are between 1 and sqr(n)

      Sig: Tell all your friends NOT to download the Advanced Ebook Processor:

      --

      LedgerSMB: Open source Accounting/ERP
  17. Re:More than just two contests by IdiotBoy · · Score: 1

    You need only search the space up to the square root of the first number, a moments thought will let you see why.

  18. Re:More than just two contests by IdiotBoy · · Score: 1

    I wasn't implying that it was easy.. if it was, they wouldn't give you $10,000 for doing it. I am merely pointing out that the original poster's comments had a fatal flaw.

  19. No, don't by ch-chuck · · Score: 1

    GNU bc 1.05 can't even multiply 10(bignum 1)7779
    *
    106603(bignum2)62808643 w/o segfault & core dump. Bah.

    [lameness filter - those are #'s, not CAPS!)

    --
    try { do() || do_not(); } catch (JediException err) { yoda(err); }
    1. Re:No, don't by The+Flymaster · · Score: 1

      No...all numerals are lowercase. Uppercase 1 is !, and uppercase 2 is @...etc. The reason you rarely see uppercase numerals on computers is because of the binary issues. !))!)! is much harder to read than 100101.

  20. Clue: use 'bc' by ch-chuck · · Score: 2

    the 'arbitrary precision calculator' that *nix people (usually) have it right at their fingertips. Don't know what Windows users have to accomplish the task.

    --
    try { do() || do_not(); } catch (JediException err) { yoda(err); }
  21. Damn! by DJPenguin · · Score: 2

    All those numbers are odd. I had an idea about dividing by 2 :)

  22. My user number is prime by weefle · · Score: 2

    Nyah nyah!

    1. Re:My user number is prime by eMilkshake · · Score: 1

      Which you found out using FactorPad for your Palm, right?

  23. Re:Imagine if you will.. by Turmio · · Score: 1

    What "the government"?

    Oh yes, you must be one of those Americans, the great nation that inhabits planet Unkasam all alone. And that planet is ruled by a government, better known as The Government.

    Seriously, what's your puny government going to do if, say, Chinese, "came out tommorow with the solution for *all* of these"?

    Yet again someone has to say this, but you never can't emphasize this message enough: Your're not alone, Yanks.

  24. Re:Oh come on, I could to it... by Aphexian · · Score: 1

    Prior art -- think distributed.net

    Now go home and wait for a visit from the patent lawyers like a good little heathen.

  25. Re:Imagine if you will.. by timster · · Score: 2

    Yes, someone could luck out. But do you realize what you are saying?
    As an example, radioactive decay is, at the atomic level, a fairly random process, and the atoms are basically isolated. Any given atom could just pop at any moment, and at any given moment some of them are.
    Realize now that, with some "luck", it would be very possible for a whole bunch of atoms to decay at once. There's nothing keeping them going at any certain rate other than probability; it's incredibly unlikely that any large number of atoms will do the same relatively unlikely thing at around the same time.
    In this case, I would say that if you use your computer to try some random prime numbers, it's far more likely that you'll explode than find the correct numbers "on accident". Not a good risk, I say.

    --
    I have seen the future, and it is inconvenient.
  26. Re:Blame Matthew Broderick by timster · · Score: 2

    Hah, amen. I used to know a guy who would always tell people that various government agencies were after him for his uber-hacking. He'd even pretend, like if he was driving his car there was a good chance he'd start skidding down side streets because someone was "tailing him".
    Then again, he wasn't anything I'd call a "hacker", in any sense of the word. The best one-word description of him would be "wannabe".

    --
    I have seen the future, and it is inconvenient.
  27. What would be interesting... by zook · · Score: 1
    It seems a lot of work, and not terribly interesting thing, to find the factors of some particular large number. Enough cycles and a reasonable algorithm, and someone will (eventually) get it.

    Of course, I'm sure that that is not what RSA Labs is hoping for. What would be much more interesting is if someone can come up with a method that doesn't take a massive number of cycles and could be quickly used on any such number.

    Or more interesting yet, prove that one needs to work their butt off to factor it.

    If one could either one, the prize would be much more than 200 grand.

  28. Re:I'm sorry by zook · · Score: 1
    But there is no way for you to factor any of these numbers while you're still alive.

    That we know of. Prove it.

    (And then we can all rest a bit easier when we use RSA, for example.)

  29. Re:proof: by zook · · Score: 1

    There's actually a million dollar prize for solving that one. I guess if you solve it the right way you should be able to quickly claim your 1.6 mil.

  30. Re:Translation by gorilla · · Score: 4
    You're wrong - we do not have a generalizable method of factorization. This means that if you factor the RSA-576 number then there is nothing which will make it any easier to factor another random 174 digit.

    RSA is offering this money to show that the RSA public key method IS secure, because we can't factor these numbers.

  31. Re:Imagine if you will.. by CoughDropAddict · · Score: 2

    Someone coming out tommorow with the solution for *all* of these. For everyone. And having it verified.

    I've thought about this before, but more from the perspective of "what if by some freak accident I was to stumble on the algorithm that makes factoring trivial? what would I do?"

    Now, I don't believe everything I see in movies, but I also don't feel like putting my welfare or my sanity on the line by exposing something so momentous and dangerous. A lot of powerful people depend on the difficulty of factoring to keep their stuff secret.

    Here's what I think I would do: Send an encrypted e-mail to Bruce Schneier describing the algorithm (he must have a public key posted somewhere), and forward it through a dozen anonymous remailers. Preface the explanation with this: The existence of the algorithm I am about to describe is terrifying to me, and I am not fit nor willing to take responsibility for it. I trust your judgement in how you feel is the best way to proceed.

    --

  32. Re:Imagine if you will.. by greenrd · · Score: 1
    Surely the efficient algorithms mentioned above would be more efficient than guessing?

  33. Not running out of keys yet. by bharlan · · Score: 2

    Bruce Schneier wrote in Applied Cryptography (p. 258): "If you could store one gigabyte of information on a drive weighing one gram, then a list of just the 512-bit primes would weigh so much that it would exceed the Chandrasekhar limit and collapse into a black hole..."

    --
    (Reality reasserts itself sooner or later.)
  34. Translation by First+Person · · Score: 3

    The first gradstudent to develop a serious quantum computer is gonna pick up a lot of cash.

    --
    Given one hour to live, the student replied: "I'd spend it with professor FP who can make an hour seem like a lifetime."
    1. Re:Translation by anacron · · Score: 3

      Yes, the grad student will. But has anyone figured out why these numbers were picked? Isn't it true that for every number we factor the set of available "secure" keys shrinks by 1?

      Isn't this almost like turning the community against itself "Here, factor this number and win 200k", but by doing so we're actually breaking a number that's important to us in some way we just don't know how? I mean, for someone to pay 200k for a SINGLE number to be factored, the payoff on their side must be enormous. What's their ROI for the 200k they've spent? More importantly, WHY are they asking us to do this?

      .anacron

    2. Re:Translation by ichimunki · · Score: 3

      If you read their FAQ, you will get most of your answers. They estimate that in order to get the factors for a 760 bit key in a year or less it would take 215,000 Pentium class machines, each with 4gb of RAM (although they say a 430 bit key is trivial to factor). That's a lot of horsepower for a single set of factors. You'd need to rerun all that for each key you wanted to crack. Their purpose seems to be twofold: to prove how hard it is to get around the longer key security, and to encourage people to seek better algorithms related to factoring.

      --
      I do not have a signature
    3. Re:Translation by FreeMath · · Score: 2
      Yes, the number of secure keys decreases by one, but there are (by my calculations) 1.89e151 512bit prime numbers. We will have quantum computers before we run out of numbers.

      They are doing this to continually prove how difficult it is to factor numbers. Even with everybody's new 1.7GHz P4's it still takes forever.

      --
      This sig intentionally left blank.
    4. Re:Translation by UberLame · · Score: 1

      I fail to see what makes them think it will take a 4 gigs of ram? It seems to me that at the simplest, you wouldn't need much memory at all. Only a few K (you have to old the original number, the factor you are currently looking at, some scratch space for the math, and some misc. other scratch space).

      --
      I'm a loser baby, so why don't you kill me.
  35. Re:Only Two Factors? by wolf- · · Score: 1


    From earlier on in the FAQ:

    Each number is the product of two large primes, similar to the modulus of an RSA key pair.

    So, 4 factors,
    1, unknown1, unkown2, and the test number itself.

    Only need to submit the 2 primes from the middle pair.

    --
    ----- LoboSoft specializes in Digital Language Lab
  36. Title should have been "Win $635,000 in ..." by Neter · · Score: 1


    If you have enought cycles to factor the 2048 bit challenge any time in the near future one would assume that you could easily factor the lesser numbers as well.

  37. RSA expects to pay the $10,000 within the year by Neter · · Score: 2


    An interview on CNet radio yesterday with the chief research guy @ RSA said that RSA expects to pay the first sum ($10,000) within a year.

  38. Re:Pretty sad by camusflage · · Score: 1

    RSA is in the encryption biz. They're funding (on the cheap, might I add) research into cryptography. This is like saying that Publishers Clearing House should be funding medical research instead of giving away money (and furthering their business).

    Let's say, for sake of argument, that someone comes up with a new algorithm for finding the primes that generate a key, and six weeks from now, they manage to clean up and take every prize offered. For a total outlay of $635,000, we find out that encryption based on primes is vulnerable to cracking. I think anyone would be hard-pressed to find medical research that benefits from that same amount of money to the same degree that cryptography would from the revelation that the factors from a large key can be easily obtained.

    --
    The truth about Scientology, Xenu, and you: Operation Clambake
  39. Imagine if you will.. by iamsure · · Score: 3

    Someone coming out tommorow with the solution for *all* of these. For everyone. And having it verified.

    While cool, and prestigious, and definitely worth money, the government would SURELY seek to either supress his findings, or acquire them.

    If someone came up with an entirely new number theory solution that allowed easy factoring of huge numbers (ala Sneakers), the government would indeed be something to fear.

    Not to mention, very few secrets would be safe.

    Just an interesting thought for a boring day..

    1. Re:Imagine if you will.. by Negadecimal · · Score: 1

      Problem with just releasing the algorithm is that you take down the world's encryption systems in a single blow. That's a pretty mean thing to do.

      I'd recommend giving the world a chance to update its mathematics first: apply the algorithm a few times to prove that you've got it, and then let the world know that you have a dead-man-switch in some random location, just waiting to release the algorithm should something happen to you.

    2. Re:Imagine if you will.. by billh · · Score: 2

      Okay, let's say I'm bored, and I am not familiar with the details of these challenges. I just have to pick two prime numbers that, when multiplied, equal the result?

      I'm serious here. I know it is one shot in a trillion or 10, but simply as an exercise, is that all there is to it?

    3. Re:Imagine if you will.. by billh · · Score: 2

      Okay, this is a serious question. I'm not much on math...

      Let's say I had a list of primes (which, I suppose, I would have to find first). I pick two, and want to multiply them. Can I use a computer? Is this one of the problems? I tried some large number operations with bc, and it core dumped on me.

      Call it a shot in the dark, call it boring, but it would be nice to have a list of prime numbers, pick a couple, check them, and see if I hit it. Not that I expect to, but I'm always looking for a way to alleviate the boredom of confernece calls...

    4. Re:Imagine if you will.. by UberLame · · Score: 1

      Now it seems to me, that if a program was written that just sits there guessing, and that program was run on numerous computers, that someone could luck out. There probably could so some optimizations applied to that guessing to help improve acuracy.

      Actually, I think I might have an idea (related to above, but not quite the same). I think I shall have to try coding it one of these evenings. Problem is I first need code to allow me to multiply and divide such large numbers.

      --
      I'm a loser baby, so why don't you kill me.
    5. Re:Imagine if you will.. by 3am · · Score: 2

      okay, a slightly more detailed number than '1 in a trillion or 10' can be made.

      first of all, you need to know all the prime numbers less than the square root of the number you're trying to factor (up to appr 85 decimal digits). Now, due to the prime number theorem (see Riemann for outline, Hadamard & Vallee Poussin for proof) you can know that the number of prime numbers less than 'n' is on the order of n/log(n). Now, the odds you'll pick the correct pair are 2 out of that number, or:

      2/[(sqr_root(RSA-576)/log(sqr_root(RSA_576))^2]

      now, i just don't care enough to work that out, but i think you'd have a better shot if you started buying superball lotto tickets...

      --

      A: None. The Universe spins the bulb, and the Zen master merely stays out of the way.
  40. Re:Wonder if Distributed.net will pick this up? by po_boy · · Score: 1

    sure, see http://www.cafepress.com/nsa1984.
    Hope it helps.

  41. Just to get us started ... by James+Ezick · · Score: 5

    Well let's see ...
    2 ... None are even ... nope.
    3 ... None of the digit sums is divisible by 3 ... nope.
    5 ... None end in 5 or 0 ... nope.
    7 ... Well, I'm out of ideas.

    1. Re:Just to get us started ... by MikeTheYak · · Score: 2
      I don't know how to help you with 7, but I did just save you a millisecond with 5.

      Yeah? How long did it take to read your post?

    2. Re:Just to get us started ... by Matthaeus · · Score: 1

      The other prime could also be 5, you know. Although using a perfect square for a RSA key probably violates security specs all over the place.

    3. Re:Just to get us started ... by pangu · · Score: 1

      which leaves just 7 and 9...

    4. Re:Just to get us started ... by pangu · · Score: 1

      I know, I hit submit before thinking. My fault.

  42. Well, they're not even by Tony+Hammitt · · Score: 2

    I'm giving up. Maybe I should have stayed in grad school.

  43. Conspiracy! by Spankophile · · Score: 2

    Distributed computing power has become so abundant and easily reachable (seti, dist.net, etc), that the entities with interests in preserving and justifying there existance (seti folk, protein structure folk, encryption folk)have to survive by distracting us with a limitless abundance of distributable contests.

  44. use those cycles for something useful.... by neowintermute · · Score: 1

    If you really want to volunteer your cpu cycles, you can look for the cure for cancer by using this client:

    http://www.ud.com/home.htm

    Or, you could keep file sharing freedom alive by running a Gnutella client!!!

    http://www.bearshare.com

    If you really want to volunteer your hardware, do it for something that will help people, please.
    http://www.redpolygon.com
    http://www.hyperpoem.net

  45. Re:would this be cheating? by billh · · Score: 1

    Similar things have been done. I've seen trojans that install the distributed net client under someone else's e-mail address. Mostly on lab type machines. Zip up your client with some program, put it on gnutella, and watch your stats go up.

  46. T-Shirt by billh · · Score: 2

    Try google:

    http://www.eff.org/Misc/Graphics/nsa_1984.gif

    Now go to cafepress, and have one printed.

    1. Re:T-Shirt by RevAaron · · Score: 2

      Not at cafepress. Perhaps that why it was mentioned in the parent post. WOW!

      --

      Working toward a usable PDA environment in the spirit of Newton OS: Dynapad
    2. Re:T-Shirt by pgpckt · · Score: 1

      I don't want to set up a store to sell these, and custom printings at most stores require a minimun quanity of six in most cases.

      --
      Lawrence Lessig is my personal hero.
  47. I'm sorry by randombit · · Score: 2

    But there is no way for you to factor any of these numbers while you're still alive. Last year the RSA 512 bit number was factored. It required about 9 months on ~400 Alphas and Pentium IIs, plus (and this is the kicker), about 4 weeks on a really huge supercomputer (I think about 2 weeks at the start, and 2 and at the end). You need like 4 gigs of RAM (at least, more as the numbers get longer) to do this.

    The supercomputer steps cannot be done in parrallel - it's a huge linear algebra problem. You would have to find a new factoring algorithm if you wanted to make it a distributed.net-style problem.

    1. Re:I'm sorry by Xilman · · Score: 1
      But there is no way for you to factor any of these numbers while you're still alive.

      I don't intend dying that early - but who knows?

      Some of us are already thinking about the 576-bit number with a $10k reward. It should be finished in less than a year. It's only ten times harder than the 512-bit number we completed two years ago. The 640-bit challenge is about ten times harder again, and so eminently reasonable in the near future.

      The 2048-bit number is well beyond present capabilities.

      Paul

      --
      Lasciate ogne speranza, voi ch'intrate
  48. Re:More than just two contests by cheezus · · Score: 1
    RSA have several different levels of prizes.

    Here is the list:

    * 576 bits - $10,000
    * 640 bits - $20,000
    * 704 bits - $30,000
    * 768 bits - $50,000
    * 896 bits - $75,000
    * 1024 bits - $100,000
    * 1536 bits - $150,000
    * 2048 bits - $200,000

    Yeah, I got up to 1024 bits but then I ran out of lifelines and regis goaded me into picking the wrong factor.

    ---

    --
    /bin/fortune | slashdotsig.sh
  49. any software recommendations? by cheesyfru · · Score: 1

    It'd be great to find some software that's able to work on these problems during my spare CPU cycles. Who knows the scoop on this? It's worth a shot, I'm sure the odds are at least slightly better than winning the lottery!
    ---
    Josh Woodward

    1. Re:any software recommendations? by robiewp · · Score: 1

      I would use mathematica... but if you wanted to win all it would take is a humungus beowolf cluster and mathematica running under linux (it is capable of striping algebraic problems such as this). You could build one out of dual 1.3 ghz thunderbirds and 100mb eathernet with a buncha matrix switches for about 200,000 dollars, and finish the problems in a few months

  50. would this be cheating? by jon_c · · Score: 2

    Create a internet worm that uses your idle clock cycles to find the number, and sends it back to me once it's found it. I would use anonymous Usenet for communication: requesting jobs, posting jobs and (hopefully) posting the current solution.

    The reason for not making a large (voluntary) distributed project is because you'll probably have to split the money with the lucky dope that found the number, this way you get to keep the money.

    -Jon

    --
    this is my sig.
    1. Re:would this be cheating? by daveisoverlord · · Score: 1
      As billh said, it has been done. The Bymer worm/Dnet.Dropper infected my wife's machine.

      It's actually a pretty cool idea. Distributed.net took him out of the contest of course, but still...

      --
      The perception of reality is more important than reality itself.
  51. Re:More than just two contests by soulsteal · · Score: 2
    ok, so the max number represented by 576 bits is 24733040147310453406050252101964719003513134910121 18399140630560928972251065318671703164010612430449 89597671426016139339351365034306751209967546155101 893167916606772148699136

    While I am without the ability to actually check the number you've just provided, I know it should at least be odd, which your number isn't. The max # generated by 576 bits would be 2^576 -1.

    2 times itself 576 times would be even. Subtracting 1 would then make it odd.

    You are the weakest link, goodbye!

  52. Re:More than just two contests by sommere · · Score: 2
    ok, so the max number represented by 576 bits is
    247330401473104534060502521019647190035131349101 21 18399140630560928972251065318671703164010612430449 89597671426016139339351365034306751209967546155101 893167916606772148699136
    so, say you wanted to solve it in a lunar month.You would need to try something on the order of
    883322862403944764501794717927311392982611961075 75 65711216537717603472325233280970368442895044394463 91420255092914783354826303693952682892741236268221 0470282735956148167826
    factors per day or
    368051592668310318542414465803046413742754983781 56 52379673557382334780135513867070986851206268497693 29758439622047826397844293205813617871975515111758 769595113998172840326
    per hour or
    613418654447183864237357443005077356237924972969 27 53966122595637224633559189778451644752010447496155 49597399370079710663073822009689363119959191852931 2826585233302880672
    per minute or
    102236442407863977372892907167512892706320828828 21 25661020432606204105593198296408607458668407916025 91599566561679951777178970334948227186659865308821 880443087221714677
    per second....

    now distributed.net is getting 127Gkeys per second... or about 127000000000 keys per second... look at the difference in the number of digits... RSA won't have to pay on that for a LONG time about
    617542959210482443413008607634637255048426967358 41 91243355002259457438595524172029124979552458558672 34341034133758742263188689327699355242471411637798 00504
    years at that rate if my calculations are right....

    ---

  53. very bad timing by Mr.+Sketch · · Score: 1

    After all, ICFP is tommorow, and I can't work on both at the same time. Oh well, I guess I'll have to wait until sunday afternoon to start cranking on this one. Or I could just say screw ICFP since this one has potentially higher rewards :).

  54. Method of doing this? by MajroMax · · Score: 1
    I would be doing this now, but I have one slight miniature problem:

    Error: 'long long long' is too long for GCC

    Is there any nice, easy way around this that will let me not rewrite division?

    --
    "Evil company X is threatening to restrict our rights! Let's all get together to stop--OOOH! SHINEY!!!" -- AC
    1. Re:Method of doing this? by pdiaz · · Score: 2

      GNU MP is a library for arbitrary precision arithmetic, operating on signed integers, rational numbers, and floating point numbers. It has a rich set of functions, and the functions have a regular interface.
      home page for GNU MP

      --
      Make It Secret . Free JavaScript implementation of AES for your browser
    2. Re:Method of doing this? by Liquid(TJ) · · Score: 1

      Everything here is unsigned, could you maybe use size_t instead? I'd check it out myself but I'm like, lazy and stuff.

  55. Re:Pretty sad by KingAdrock · · Score: 1

    Not only that, but I'm willing to bet if we could start effectively factoring such large numbers, somewhere -- somehow, a medical breakthrough would come from it!

  56. It easy, all these number can be factored by ... by regen · · Score: 2

    42 of course. :)

  57. Re:Raise the Prize amount please. by Tuzanor · · Score: 2

    lets not forget that computers do this many times a second

  58. Bad timing by jlanng · · Score: 1

    We've only just put their cancer cure on hold to help SETI look for lights in the sky. And now this??

  59. Re:Raise the Prize amount please. by istartedi · · Score: 2

    Maybe they should have based the prize ammount on one of the factors, moving the decimal to a reasonable position of course.

    So, if you just randomly pick factors what are your odds, and how does it compare to the lottery when computed on an average PC? Of course unlike lotto, you don't have to pay to play unless you really decide to go all out and purchase additional hardware, which would probably not be justified.

    --
    For all intensive purposes, "whom" is no longer a word. That begs the question, "who cares"?
  60. Re:More than just two contests by Martin+Blank · · Score: 1
    I seem to remember in Applied Cryptography that Bruce Schneier suggested that at a most efficient possible level of computing, harnessing all of the sun's energy for the next four billion years would not be enough to brute-force a 4096-bit key. While keys ranging from 576-bit to 2048-bit keys are theoretically far more simple, we're still nowhere near that level of computing efficiency or power, so unless someone figures out a far more elegant manner of cracking such numbers than are currently in use, RSA may as well spend the prize money, since they'll never have to award it.

    Makes me wish I had known about the NSA's recruitment programs in high school....

    --
    You can never go home again... but I guess you can shop there.
  61. Re:More than just two contests by Martin+Blank · · Score: 1

    I really should read my posts for clarity before clicking Submit.

    I meant that the 2048-bit wouldn't be solved anytime soon.

    ::sigh :: I need some Jolt.

    --
    You can never go home again... but I guess you can shop there.
  62. Re:Raise the Prize amount please. by taliver · · Score: 1
    Well, my recent attempts at math haven't proved too good, but let's see if I can take a shot at your odds:

    617 digits, and with the assumption that the factors are comparable length means they are in the 300 digit area. Which means that you could guess one with about a 1 in 10^300 chance.

    In lotto terms, you are about 10^294 times more likely to win guessing lottery numbers than trying to guess here. However, the guesses here are free, so you're price/probability of winning ratio is infinite.

    --

    I demand a million helicopters and a DOLLAR!

  63. Re:Raise the Prize amount please. by taliver · · Score: 1

    Er... yeah. Zero. Sorry, the Probability/Price ratio is infinite. (My math track record on /. sucks.)

    --

    I demand a million helicopters and a DOLLAR!

  64. Software? by Teflon+Coating · · Score: 1

    What software should i use for this? They don't offer anywhere to download any, can i use the distributed.net client?

  65. Re:Sneakers by doorbot.com · · Score: 2

    Didn't the mathematician guy (who got killed) use his solution of "factoring large primes" to break encryption?

    Please explain how that is possible.

  66. Warning to Slashdot users workin on this! by dstone · · Score: 5

    Just for the hell of it, I tried hitting "Submit" with a blank submission of factors. Mostly, I was curious to see if they were using SSL for submissions because what if someone was snooping and intercepted my submission and then submitted it themself. Hey, it could happen!

    Anyways, no they don't use SSL, but more surprisingly, they care who your referrer was. And they say "slashdot not found in list of allowed referrers". Not sure if this would actually prevent a legitimate submission, but maybe you don't want to risk clicking thru Slashdot to RSA when you find the real factors. (Especially considering the lack of SSL.)

    Error Message:
    slashdot not found in list of allowed referrers.
    Required Field: email has not been completed.
    Required Field: Submitters has not been completed.
    Required Field: challnum has not been completed.
    Required Field: p has not been completed.
    Required Field: q has not been completed.
    Required Field: description has not been completed.
    Please use your 'back' button to return to the Web form.

  67. More than just two contests by MarkusH · · Score: 2

    RSA have several different levels of prizes.

    Here is the list:

    • 576 bits - $10,000
    • 640 bits - $20,000
    • 704 bits - $30,000
    • 768 bits - $50,000
    • 896 bits - $75,000
    • 1024 bits - $100,000
    • 1536 bits - $150,000
    • 2048 bits - $200,000

    Good luck on getting those anytime soon.

    1. Re:More than just two contests by snoopy75 · · Score: 1
      You need only search the space up to the square root of the first number, a moments thought will let you see why.

      And yet, the square root of
      251959084756578934940271832400483985714292821262 04 03202777713783604366202070759555626401852588078440 69182906412495150821892985591491761845028084891200 72844992687392807287776735971418347270261896375014 97182469116507761337985909570009733045974880842840 17974291006424586918171951187461215151726546322822 16869987549182422433637259085141865462043576798423 38718477444792073993423658482382428119816381501067 48104516603773060562016196762561338441436038339044 14952634432190114657544454178424020924616515723350 77870774981712577246796292638635637328991215483143 81678998850404453640235273819513786365643912120103 97122822120720357
      is.... larger than my hand calculator can do. But it's still got to be ridiculously large. So it's still not as easy as you make it out to be.

  68. Re:Only Two Factors? by vwp · · Score: 1

    Actually, having only 2 factors is (part of) what makes it so difficult. The more factors there are, the smaller each individual factor will be (on average), and hence the smaller the amount of time needed to find them.

  69. Distributed computing legal advice of the day by Rosco+P.+Coltrane · · Score: 2

    Just make sure you don't rig up all the computers at your workplace to win the prize.

    --
    "A door is what a dog is perpetually on the wrong side of" - Ogden Nash
  70. Make $199,999 FAST!!!!!! by NoOneInParticular · · Score: 1

    Are you also tired of doing the same old job time and time again. HERE is your possibility for getting rich without leaving the comfort of your own home... etc.

    Too bad /. doesn't allow me to fully mimick the capitalization, but you get the picture.

  71. Who needs a computer? by alen · · Score: 1

    Can't anybody do this in their head?

    1. Re:Who needs a computer? by Geek_Talking_Smack · · Score: 1

      Raymond? I gave my love a sig, and she smoked it.

  72. Found it by Darth_Burrito · · Score: 1

    (Kidding)
    Factor Submission Form
    Submitter Nam(s): Joe Bob
    Contact Email Address: joebob@fake.com
    RSA Challenge Number:RSA-2048
    First Factor: 38927598246791283709823572098375983275987358927598 738750187350...
    Second Factor: 37498278736897245097604376029847602834760982734607 2306987308763087039476092834760298374609827346908. ..
    Description of Effort: Looked at the yellow post-its stuck to the competition organizer's monitor.

  73. can anyone find out...... by canning · · Score: 1
    what I have to factor for the ten dollar prize. I forgot my lunch money today and ten bucks would really come in handy.

    Is there anyone out there that's against cracking a 64bit encryption key?

    --
    I love the smell of Karma in the morning
  74. Re:Primes by Jucius+Maximus · · Score: 1
    "I bet they all turn out to be primes :)"

    Read the site! "A set of eight challenge numbers, ranging in size from 576 bits to 2048 bits is posted here. Each number is the product of two large primes, similar to the modulus of an RSA key pair."

  75. Re:Oh come on, I could to it... by Jucius+Maximus · · Score: 1
    "With 1,000,000,000,000,000 or so of my closest friends, everybody take a chunk of integers..."

    Do you live in an enormous ant colony or something?!?

  76. Re:4 GB of RAM - big deal by plcurechax · · Score: 1
    How about enough for over 215,000 machines with 4GB of RAM, that's set you back...ah, over $ 145,000,000 dollars, plus shipping and handling.

    See the RSA Security FAQ, How Much Does It Cost?

  77. Re:Software? Brute force is not the only way by plcurechax · · Score: 1
    Since there is no known way to do factorization of large numbers aside from brute force

    That is incorrect.

    There are numerous algorithms that are more efficient that dumb brute force. That doesn't mean that will find the answer quickly, but vastly quicker than naive brute force attempts.

    See the RSA FAQ, What are the best factoring methods in use today?

  78. Beowulf Cluster won't work actually by plcurechax · · Score: 1
    A typical Beowulf cluster is made up of numerous modest machines with typical RAM, and moderate networking speed. Today (July 2001) that may be say 20 boxes with dual Intel Pentium III @ 733 Mhz, with 256MB of RAM, and 100Mbit Ethernet to a dedicated switch.

    For trying to use GNFS General Number Field Seive or NFS (Number Field Seive), you need more RAM per CPU (e.g. 4GB per CPU) if you want to factor numbers in the RSA-155+ range.

    Since I've not used NFS, GNFS for any projects, I think the network bandwidth limitations are okay, except in the last stage which I think it a linear matrix reduction.

  79. Re:techniques to factor big numbers by plcurechax · · Score: 1
    The techniques do work, they just require a lot of computing resources and time.

    It is expected that the smallest challenge will be solved within 1 year or so. To break the high-end of the range in the next 2-3 years would require an advance in the state-of-the-art in knowledge about factoring.

    I wouldn't expect a breakthrough because the problem is fairly old, and well understood, but a definate improvement is possible.

  80. Re:Software recommendations: GNFS by plcurechax · · Score: 2
    From: http://dbs.cwi.nl:8080/cwwwi/owa/cwwwi.print_proje cts?ID=12

    CWI has several source code license agreements with companies in The Netherlands, USA, Germany and France which allow them to use the Number Field Sieve factorization code as this was and is being developed by P.L. Montgomery, A.K. Lenstra, M. Elkenbracht-Huizing, S. Cavallar and B. Dodson. On a non-commercial basis, the NFS source code has also been made available for research purposes to other cooperating groups. A group of the Royal Institute of Technology in Stockholm (Hastad) has used this code as a basis for factoring a hard 512-bit challenge number in October 2000.

  81. Wrong by plcurechax · · Score: 2
    What do you think the General in General Number Field Seive (GNFS) stands for?

    See the RSA Crypto FAQ.

  82. techniques to factor big numbers by plcurechax · · Score: 5
    If you want to actually try this, there are several things to realise, first you need a lot of computing power, including at least one very large multiprocessor machine with several (>4) GB of RAM. Think high-end Alphas, slightly dusty Crays, think big.

    The current record factorings were done with the GNFS (General Number Field Sieve).

    GNFS consists of a sieving phase that searches a fixed set of prime numbers for candidates that have a particular algebraic relationship, modulo the number to be factored. This is followed by a matrix solving phase that creates a large matrix from the candidate values, then solves it to determine the factors.

    The sieving phase may be done in distributed fashion, on a large number of processors simultaneously. The matrix solving phase requires massive amounts of storage and is typically performed on a large supercomputer.

    Some pointers:

    In case you haven't noticed...It isn't easy, and cannot be fully solved using a distributed.net technique.

    to factor a 760-bit number in one year would require 215,000 Pentium-class machines, each with 4 Gigabytes of physical RAM.

    to factor a 1620-bit number in one year would require 1.6 x 10^15 Pentium-class machines, each with 120 Terrabytes of physical RAM.

    Good luck.

    1. Re:techniques to factor big numbers by Eryq · · Score: 3
      You forgot the massively-parallel BINOMIAL algorithm: By Infinite Number Of Monkeys In A Laboratory.

      I started the task at 8:00 this morning, and by 9:32 a shrill schreeching sound told me that one of the monkeys had solved the 1620-bit number.

      Now if I could just figure out which one...

      Plus, an infinite number of bananas costs more than my prize money. :-( And don't get me started about the mess they've made...

      --
      I'm a bloodsucking fiend! Look at my outfit!
    2. Re:techniques to factor big numbers by Genoaschild · · Score: 1

      You would need a hell of a lot of CPU cycles those types of numbers by trial and error. In theory, if you could make the numbers somehow linear with a formula using Logarithms, derivatives, etc. you could highly simplify the logic in calculating these. Also, in theory, their is atleast one formula that will give you the amount of compression you need in order to perform this task. Problem is, factorials are not that linear and trying to get them linear is a major task. If a person could find that formula, they could just solve for N and get the answer using many less CPU cycles. Trying to find the formula is the problem.
      ----

      --
      Just because a bunch of people believe or do something stupid, doesn't make it any less stupid.
  83. Of course... by geekplus · · Score: 1

    I'd rather trade $2048 for a 98-digit salary any day of the week...

  84. Re:It easy, all these number can be factored by .. by UberLame · · Score: 1

    No, none of those numbers are divisible by 42, because if they were, they would also be divisible by 2 and 21, and none of the numbers are divisible by 2.

    --
    I'm a loser baby, so why don't you kill me.
  85. Are you sure it is by jsse · · Score: 2
    1. Re:Are you sure it is by Eric+Destiny · · Score: 1
      sarcasm \Sar"casm\, n. [F. sarcasme, L. sarcasmus, Gr. sarkasmo`s, from sarka`zein to tear flesh like dogs, to bite the lips in rage, to speak bitterly, to sneer, fr. sa`rx, sa`rkos, flesh.] A keen, reproachful expression; a satirical remark uttered with some degree of scorn or contempt; a taunt; a gibe; a cutting jest.

      The sarcasms of those critics who imagine our art to be a matter of inspiration. --Sir J. Reynolds.

      Syn: Satire; irony; ridicule; taunt; gibe.

      Source: Webster's Revised Unabridged Dictionary, © 1996, 1998 MICRA, Inc.

      "I am a man, and men are
      animals who tell stories."

      --

      "The meek shall inherit the earth, the rest of us shall go to the stars." Isaac Asimov

  86. It's never to late to start now by jsse · · Score: 2

    For those who want some money but don't know how can start here.

  87. Raise the Prize amount please. by egommer · · Score: 5

    Yes I am planning on using all my school labs computers to win this one. But I only ask one favor.

    Can you raise the prized to $415,000 instead. I might need it.

    --
    Two Towers-Two Worlds.One seeks triumphs and freedom for man.The other deems man unworthy and wrecks them.
  88. What if... by Rogerborg · · Score: 2

    ...someone (think rich, dumb and unethical) used (or even intended to use) those factorable numbers to encrypt some original content, then called the DOJ and screamed "DMCA" and that evil software pirates were trying to crack their encryption?

    Stupid scenario? Really? In the context of the DMCA, nothing's beyond the pale. Remember the SDMI cracking challenge?

    • SDMI: Go ahead, crack the encryption.
    • Researcher: Done it. That was easy. Want to know how?
    • SDMI: Sure, if you want to go to jail.
    • Researcher: Say what?
    • SDMI: No, say nothing, trusting fool.
    --
    If you were blocking sigs, you wouldn't have to read this.
    1. Re:What if... by come_sucker · · Score: 1

      And exactly how would they encrypt something with that composite? You would need to have both factors in order to compute the public and private exponents (through the Euler totient function), and I believe that RSA burned the hard drive with the factors on it. Unless they ran those factors through a key generator, I doubt that anybody can sue you for trying :-)

  89. a few years salary? by kurt555gs · · Score: 1

    Yes, givin the climaye for system engineers these days $10,000 BUX might be a few years salary

    --
    * Carthago Delenda Est *
    1. Re:a few years salary? by jrp2 · · Score: 1

      Yes, givin the climaye for system engineers these days $10,000 BUX might be a few years salary

      I guess they are not very good at math. Might explain why they are having a contest to have others do math for them ;)

      --
      The only athletic sport I ever mastered was backgammon - Douglas William Jerrold
  90. People are going down the wrong path.... by jcochran · · Score: 1

    Actually, everyone is going about this wrong. The real problem is finding the multplicative inverse of an exponent modulus N where N is the product of 2 large primes. Currently, we have a simple way of calculating this inverse *if* we have the factors of N. But, we don't know if that is the only easy method of calculating this inverse. The chain of logic I'm seeing is like this.
    1. We need to calculate d using e and N.
    2. d is easy to calculate if we have the factors to N.
    3. We need to calculate the factors of N

    To my way of thinking, this reminds me of a similar logic chain that I saw someone do in the past.
    1. I need to find the smallest number in this array.
    2. If I sort the array, all I need to do is pick the 1st element of the array.
    3. Now I need to figure out how to sort an array.

    See the problem?

  91. Re:Wonder if Distributed.net will pick this up? by pgpckt · · Score: 1

    The link leads to a 6 years old posting. The shirt isn't avaliable there anymore. The link describes the shirt, and I am asking if people know where the shirt can be purchased today.

    --
    Lawrence Lessig is my personal hero.
  92. Wonder if Distributed.net will pick this up? by pgpckt · · Score: 3

    For those of you who are not donating your clock cycles to seti@home, you might want to try distributed.net. Right now, they are working on cracking a 64bit encryption key, which is also a contest from RSA securities. They are also working on finding more Optimal Golomb Rulers, so it seems that trying to factor this really huge number would be a nice fit. Take a look at the RC5 stats here. They are nifty.

    It may be problematic insomuch as they are already working on three projects, and spliting off into another project would be troublesome. But, there are no other serious efforts going on towards these types of projects, so I suppose us d.net fans will just have to wait and see.

    --
    Lawrence Lessig is my personal hero.
  93. proof: by 3am · · Score: 1

    P=NP is in fact true...

    I've found a remarkable proof of this fact, but there is not enough space in the slashdot comment field to write it.

    --

    A: None. The Universe spins the bulb, and the Zen master merely stays out of the way.
    1. Re:proof: by 3am · · Score: 1

      nah, don't want to spoil it :)

      actually i have my eye on the Hodge conjecture: "on a projective non-singular algebraic variety over the complex numbers, any Hodge class is a rational linear combination of classes cl(Z) of algebraic cycles"

      seems pretty obvious to me...

      (ps, my previous post is a slightly reworked and translated quote from Fermat, where he reported in his journal that he had proved that x^n + y^n = z^n had no integral solutions when n>=3 ... and we all know how that little problem turned out (Wiles). i have no illusion of my total inability (or perhaps the intrinsic intractibility) of the P=NP problem... )

      --

      A: None. The Universe spins the bulb, and the Zen master merely stays out of the way.
  94. Clustering.. by roguerez · · Score: 3
    I think you need a Beowulf cluster to crack one of these.

    Can you imagine that? :-)

  95. Only Two Factors? by 3ryon · · Score: 1
    Quote from the contest page FAQ:
    Enter the name(s) of the submitter(s), the challenge number factored, the two factors, and an e-mail address at which RSA Labs may contact you.
    Does the answer only include two factors? I'm not saying that's easy, but it's a *ton* easier than I thought it would be.
  96. Re:Oh come on, I could to it... by spacefem · · Score: 1

    No way, that's crap! They can't patent the idea of running a program on a bunch of computers, especially if it's all your code, can they? I guess I shouldn't act surprized by what can be patented now, but if any of us got in trouble for that it would be insane, that's like patenting the idea of using jet engines to break land speed records, it's just the only way to solve the problems, no one group can take that can they?

  97. Oh come on, I could to it... by spacefem · · Score: 2

    With 1,000,000,000,000,000 or so of my closest friends, everybody take a chunk of integers, give out some factoring code, and start grinding away every night. It all in the organization, think seti@home.

    1. Re:Oh come on, I could to it... by Unknown+Bovine+Group · · Score: 3
      You work for the US Patent office don't you?

      --
      m00.
  98. Lottery alg. by Antoshka · · Score: 1

    I wonder if there is any guessing algorithm that works on a reasonable hardware in a reasonable time and still has more chances than any regular lottery with similar prizes... Yes, I know that lotteries is a tax for those who don't know math, I just don't think that far.

    --
    Don't say No, say May be
  99. damn... by DuncanMurray · · Score: 1

    I thought I had the money in the bag, but my calculator got an overflow error

    --
    I'll think of a funny sig later on
  100. Blame Matthew Broderick by mypalmike · · Score: 1

    Ever since Broderick played a hacker who got chased around by "the government" in the hit 80's movie "Wargames", all us American geeks have this weird fantasy about "the government" wanting our brains and being willing to kill for our knowledge. Many movies since then have picked up on this fantasy and encouraged the same sort of thinking, "The Matrix", "Hackers", and "Yentl" being prime examples. In any event, I don't think it's so much a disassociation from being part of the bigger global picture so much as a simple, yet perverse desire to be stalked by men in dark suits, ties, and shades, sporting semiautomatic pistols with silencers. A desire to be James Bond with a PalmPilot running an home-brew OS while dot matrix printers at the homestead are printing out reams of secret government documents onto green-striped paper. "The government" isn't the US government, but rather the fictional organizations contrived in these movies, internalized into geek fantasy.

    --
    There are 0x40000000 types of people: those who understand 32-bit IEEE 754 floating point, and those who don't.
  101. Pretty sad by Gzusfreak · · Score: 1

    It's pretty sad really when you think about it. We have so many diseases that have no cure... but these companies are willing to put out this kind of money to make sure thier encryption is really secure... I'm sorry, I forgot I am not a medical researcher. What am I doing wasting my time posting this message, I'd better get cracking...

    1. Re:Pretty sad by Gzusfreak · · Score: 1

      Although my original post was merely a joke, your reply is indeed insightful, and all the more inspiring to find said algorithm.

  102. don't waste your time..... by pj7 · · Score: 1

    I already know the answer....
    42!