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Thread: A smart idea to tackle bots!

  1. #1
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    Thumbs up A smart idea to tackle bots!

    I try to remove that thread but I can't...
    Oops a bug???

    original post: Have you ever suscribed to Yahoo or E-bay or Hotmail ..., ?
    Did you ask yourself why there is a picture of a word in a very strange policy that the subscription page ask you to copy in a textbox?

    I'm really happy to understand why & how now, & I felt I could share it with u.

    Pr Turing in math (For those that have a high degree math background, I'm sure u remember of Turing automates), back in the 50s wrote an paper about that philosophic question "How can we make the difference between Human thought and machine's?".
    To be synthetic Turing said that by asking specific questions like the meaning of a phrase we should be able to make the diff.

    At Carnegie Melon University (Pittsburgh), Pr Mellon had designed an experimental Turing Test serie. & one of the test is the strange picture of a deformed word that u see in yahoo subscription page. Each kind of test is commonly called a Captcha

    An application of Captchas is to fight automatic web member subscription. A flood of valid subscription could result in a site DoS with no way to fight back since the firewall sees all traffics as legit!!!

    That theory is a challenge for all IA projects. For now on 2 researchers from Berkeley in IA managed to designed an algorythm that pass through the yahoo defense (this kind of captcha is called a Gimpy) with 88% of success! But there is still manies unsolved captchas ...
    The beauty of all of that is that when a Captcha is solved by a bot, that make IA making a step forward ....

    For AOs interested in the subject, google captcha or read this !
    [shadow] SHARING KNOWLEDGE[/shadow]

  2. #2
    AO übergeek phishphreek's Avatar
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    A flood of valid subscription could result in a site DoS with no way to fight back since the firewall sees all traffics as legit!!!
    Another reason the free mail services such as homail and yahoo started doing this is so spammers can't use automated bots to get tons of email addresses. Spammers would program a bot (or have someone else do it) to signup for tons of email addresses. This was a good way for spammers to send mail without using their servers and using someone elses bandwidth. This cut down costs considerably for them.

    MSN Y! and the like started using this method so the bots wouldn't suceed. At least for a little while. You'd have to have a human in there to decypher the picture and have the human type that in.

    I realize that you posted a bot can now recognize many of these picutres and MSN, Y! and the like will have to come up with a new way to block spammers from grabbing tons of accounts.

    NETWORKER: Did you post this elsewhere?
    Quitmzilla is a firefox extension that gives you stats on how long you have quit smoking, how much money you\'ve saved, how much you haven\'t smoked and recent milestones. Very helpful for people who quit smoking and used to smoke at their computers... Helps out with the urges.

  3. #3
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    phishphreek80:
    NETWORKER: Did you post this elsewhere?
    Yes indeed Itried to change the thraed title by deleting the thread and crteate a new one by the deletion didn't work. sorry
    edit: I managed to removed the other one

    I realize that you posted a bot can now recognize many of these picutres and MSN, Y! and the like will have to come up with a new way to block spammers from grabbing tons of accounts.
    u r right again! But the IA team did manage to break the simpliest captcha: Gimpy.
    But there is many other type of.

    One that IA guys should struggle with is based on deformed(is deformed proper english, I mean a lot of photoshop filter on it) animal pics. Our mind is capable to recognize a monkey with the head like a golf ball but computer can't since there is so many possible deformation possible.

    I think captcha techniques will spread quickly in the next few years!!! .. .but its my opinion.
    [shadow] SHARING KNOWLEDGE[/shadow]

  4. #4
    AO übergeek phishphreek's Avatar
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    I think captcha techniques will spread quickly in the next few years!!! .. .but its my opinion.
    I also think that this will catch on pretty quickly. I have seen several sites other than mail services that have applied this technology.

    Heck... ticketmaster was one of the first people(s) to apply it.

    Ticket agencies would have a bot and a list of credit card numbers all setup. They'd turn their bots loose for a specific event and it would sell out in a matter of minutes. Then consumers had to go to ticket agencies to buy the tickets to an event at anywhere from double to 10x the ticket value! Ticketmaster has been cracking down on this and taking offending parties to court about it. In this case they were causing a DoS attack becuase consumers couldn't be serviced. They are also being shut down and/or fined by the authorities for this practice.

    Good thing we have something like the Better Business Bureau (at least in the states) to help fight against stuff like this.
    Quitmzilla is a firefox extension that gives you stats on how long you have quit smoking, how much money you\'ve saved, how much you haven\'t smoked and recent milestones. Very helpful for people who quit smoking and used to smoke at their computers... Helps out with the urges.

  5. #5
    The problem with these bots, is they will always be running around, i say word matching with a definition or some sort, atleast then the spammers would have a harder time, but maybe not because they could do that themselves too, or maybe pick something where the person has to move their mouse through a java application,,, either way, all of these methods can and will be broken
    sectac
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  6. #6
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    Originally posted here by sectac
    either way, all of these methods can and will be broken
    Sectac I don't c ur point!
    The whole thing with Captcha is that only human thinking can resolve it! Bots are just automates!
    With image captcha the bot must analyze the pic itself and decode it, when its a deformed string the problem shouldn't be very hard.
    But there many type of Captcha, the first bot job will be to guess what type of, and then run the proper algorithm to solve it (if existing).
    But tell me how a bot can decide what is the type.
    Another thing/example is that within a single pic u could have 4 Captchas, and the site will tell u about what part of the pic user shall answer. But the computer will a single ...

    As I said before Captcha are a real challenge to Artificial Intelligence project. And I do not think that in a close future that would be solved (Maybe in spielberg or Asimov fiction but not in real life).
    [shadow] SHARING KNOWLEDGE[/shadow]

  7. #7
    Senior Member BrainStop's Avatar
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    Scientific American

    Hey all,

    I know this is an old thread, but I figured I would re-use it rather than opening a new one ...

    Scientific American has just published an article on the evolution of CAPTCHA:

    Scientific American: Baffling the Bots

    It makes for interesting reading.

    Cheers,

    BrainStop
    "To estimate the time it takes to do a task, estimate the time you think it should take, multiply by two, and change the unit of measure to the next highest unit. Thus we allocate two days for a one-hour task." -- Westheimer's Rule

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