Bitcoin Forum

Captcha's are so annoying I figured there must be an easy way to eliminate them using bitcoin.  I would think  this would help keep the bitcoin economy going.  One idea would be a full-cycle solution so basically if you don't have any bitcoins to release the captcha in front of you you can dip in and pick up a few bits through a "send me a few bits" system - to send against the captcha payment address of course if you do have some you would just send a few bits to it and again hit the "send me a few bits back"  system . I dunno just thinking out loud .... ???

What's to prevent spammers from automatically sending bits?  Difficulty in obtaining bitcoin?  :P 

good point so maybe take out the part about getting bits of bitcoin lol ...hmm how about a system that is paralleled to the traditional captcha saying if you have bits of bitcoin send and then it passes it back to you  ?

What publio meant was what will stop spammers to automate the process of sending/receiving bitcoins to pass your protected page?

ahhh will ya true  that would suck if they come up with that lol hmmm

Coinworker.com

If you can figure out how to sell captcha solutions of 95% accuracy rate on recaptcha for less than USD $1.35 (about 0.25 BTC at todays price) per 1000 solutions, then you will have found a business model.

interesting ....never occurred to me  sounds like you know a lot about this ?

Indeed. We're currently spending about $600 a week on bulk captcha solutions from imagetyperz and get their best pricing, but I think there is still room for improvement as the service is paid by paypal or credit card. I also believe they are just reselling some foreign labor using some kind of data entry platform, and that probably involves more fees to get the payments to the individual workers who end up typing these things. Now I have no idea what country or language the actual workers who type the captcha solutions are in, but they are there doing it reliably 24/7 and I'm thinking that there must be ways to connect those workers with the $$$ being paid for the bulk services without the middle men or fees, and the end result should be the most cost competitive captcha solving service out there. Having such a service only available for Bitcoin but at a clearly better pricing will encourage the whole black-hat-seo industry to think about getting into Bitcoin simply as a matter of operational cost savings.

I had no idea about this stuff. So your basically saying there are services that have human beings breaking captcha's and people pay for them ? lol

Scalpers trying to buy up everything on Ticketmaster.com the moment tickets are released

Hmmmm good point ^^ never thought about it like that.

Or combine a bit of captcha and btc?
The image will have some random tiny amount to send them, you send it, then enter a unique receive address for the refund. That way the costs to spammers are 2 way. 1 for the btc amount, then for the btc they have to spend to go through.

So all you need is to read some numbers from a picture, enter an address, create blockchain bloat and you get your BTC back anyways? ???

Anyways: if you make it expensive to pass a captcha, you will scare off regular users, if it is dead cheap, bots would just pay.

What might work is a (web-)miner and a getwork source. Mine one or more difficulty 1 shares and you can enter. Still it might be possible for bots to mine themselves or rent hashing power, but it could have a high enough cost to keep them from your page and is easy enough to do for regular users.

Idea: Instead of a captcha, send a 1 bitcoin deposit. After a certian amount of time they determine you arent a spammer, and they send you your btc back. This could at least work on forums and wikis.

In hindsight do you find it that surprising?  Captchas exist to stop "something" automated.  That automation is obviously valuable otherwise captcha or no captcha nobody would be automating it.

If the value of the automation is > slave wages by uneducated workers in 3rd world then .... there is a business to provide "human talent" to bypass captchas.

There is a direct relationship between shares & coins.
1 diff 1 share =  1 BTC / (current difficulty)
Even 1000 diff 1 shares <= 0.07 bitcents.
So there is no real advantage to using shares instead of coins.  Coins are simply "purchased shares".

A modest fee would make bypass for the purposes of spamming prohibitively expensive.
Current captcha bypass solutions are on the order of 25 bitcents per 1K solutions.

That is 0.04 BTC per capthca bypass.   Allowing legit users to bypass the captcha for 1 bitcent would increase spammer's cost by 25x while not costing user much.

I would love a captcha bypass system for 1 cent per capthca.  Eventually as more users use the "humancent" system you could make the captcha more timeconsuming driving up spammer's cost and eventually move to a "no-captcha" system where user must pay a micro tx to continue.

So basically, if you could set it up so you have to send 25 cents worth of BTC to an address, then after a certain amount of time (a month?) you get it back...that would be no big deal to regular people. You spend a few bucks a month on captchas and get it back.

But for spammers...doing 1000 at a time, you have to spend $250. Then wait to get that back. That cuts into the monthly budget, $250 for every 1000 captchas used.

Basically, this is what I was getting at. What you could do even is do a "strongcoin" type element where you "unlock" the content - there would be a "pool of bitcoin" that could be used for people to unlock the captcha/content.

This is where I was heading with all of this. Basically, help eliminate all the hassles with captcha's.

Your first part is right. Obviously, not everyone is a spammer so they will have to figure something out.

I get it now. Yeah this would work well. You basically dont refund your users' microtransactions until they've proven themselves to not be a spammer. That could be right away if the user was invited, after some mod decides they're not, after some period of time of not being flagged as a spammer, or maybe even never (maybe those fees go towards site operational costs!) ... the possibilities are pretty wide open and I think its a great idea. I know it would thwart our bots for sure if we knew we wouldnt get the money back after being identified as a spam account. Unless the value was low enough, anyway ha ha ha. Could use this as a way to drive bitcoin adoption as well, if they dont want to, or cannot, pay the micro BTC signup fee, they can do some incredibly annoying turing test like 5 captchas in a row or something, something that would still cost a potential spammer far more $$ than usual.

http://www.megatypers.com/

But recent reviews say they've stopped paying money.

Quote from website:

"EARN OVER $200 US DOLLARS A MONTH
MegaTypers.com is a workforce management company that service institutions requiring data entry services. Our main goal is to support our client.s digitization requirements by converting scanned papers into editable digital documents. Our services also include Neural Network Text Recognition, Voice-to-text transcription and Completely Automated Public Turing Test to tell Computers and Humans Apart image recognition for the visually impaired (blind).

We.re currently looking for typers from around the globe. All you need to have to work with us is a computer with an internet connection and the ability to type at least 10 Words Per Minute. Our schedules are flexible. You can work at any hour that you want and for as long as you please. The quicker you type, the more cash you earn.

MegaTypers.com is fantastic for:

    * Mothers that stay at home.
    * Parents that need a second job.
    * Students.
    * People in between jobs.

How much you earn depends on how much you work. Our top typers earn between $100 and $250 each month! Our Rates start from $0.50 for each 1000 words typed and can go as high as up to $1.5 for each 1000 words typed. We Pay through Debit Cards, Bank Checks, Paypal, Webmoney, Liberty Reserve and Western Union."

So everyone provided some good information on both sides of the spectrum I wonder what to do next ?  Seems there is a business model any people who are programmers want to figure something out PM me. Thanks!

Catchphrase:
"My 2 cents"

Idea:
Create a company that takes deposits of 2 Bitcents instead of a Captcha and pays them back after 2 weeks. Website owners get a simple API where they embed a small image that either allows you to send 2 Bitcents to a specified address or take 2 Bitcents from your "my 2 cents"-account that you can pre-charge. If abuse/spam is reported, you don't pay the money back - so honest users can (with an investment of a few Bitcoins) post a LOT of comments (or download files, or whatever else would require a captcha) without having to mess with these silly characters without _any_ costs to them (transaction fees, if any, would be covered by the company and you can just send out a huge multi-target transaction once per day to keep blockchain bloat low) while spammers would have quite some difficulties.

I'd actually love something like this as a plugin for forums (maybe the new bitcoin forum? ::) ) too! Scammer tag? Now you pay your 2 cents per post but won't get them back... Broke forum rules? Instead of getting a temp-ban, you get a temp-pay!

1 BTC is too much, smallest satoshi demonination would work well enough to prevent spam bots easily for forums like here or GLBSE though free whitelisting seems to work fine so far. Or simply having to upload a gpg key that matched your registration email. Spam bots would esplode from all the key generation they'd have to do constantly. Bonus of keys would be PM to PM encryption.

What?  Have you thought this through?

Currently spammers (and others) pay about 0.25 BTC per 1000K captchas to bypass existing spam controls because at that price point the cost is < value of the spam.  Replacing that with a system that costs 0.0001 BTC would be worthless.  The only winners would be spammers who would see their costs fall 99.95%.

1 BTC
Currently buys 4,000 recaptchas bypasses.
Under a 1 satoshi system buys 100,000,000 "spam protected" transactions
You are moving the cost curve in the wrong direction.

1 BTC
Currently buys 4,000 recaptchas bypasses.
Under a "my 2 bitcent system" buys 50 "spam protected" transactions.
Spammers cost rise by a factor of 80x possibly making most spam prohibitively expensive.

nah, the tickets just get "magically" transferred to "Tickets Now" (owned by ticketmaster, sells at huge markups). Besides, captcha solving services usually have a response time of > 15 sec, so they're not exactly ideal for time sensitive operations.

The idea of creating a single company to do this sort of defeats the purpose of using Bitcoins.

A single company could just collect money in dollars, keep the money in people's accounts, then set up an API for companies to connect to your server where merchants can connect their APIs.


The first step, which would have many more uses than this, would be to integrate a browser plugin with Bitcoin wallets and allow people to just click on a "pay 2 refundable bitcents" button followed by a confirmation by the plugin.

This was already discussed and designed some time ago:

https://en.bitcoin.it/wiki/Contracts#Example_1:_Providing_a_deposit

Forums, wikis, etc. are usually looking for verification that people are not bots but are not usually going to charge people for the ability to post/edit. 

Agreed.  There should be a simple here I have bitcoin , here bitcoin leaves my hands , bitcoin eliminates captcha, bitcoin returned to person who sent bitcoin ....

This is true shouldn't charge to post/edit agreed. Trying to figure out the full-cycle I mentioned originally...

Typing in a few characters is harder than copying an addy, typing in the amount, and pressing send?

Also, sending bitcoins has already been automated (look at the jsonrpc API), so this would only make it easier for spammers to bypass the system.

The problem here isn't that captchas are too hard against humans, it is that they are not effective enough against computers, and they are currently at the point where making them harder for computers would make them frustrating for humans.

Sending bitcoins can indeed be easily automated but at some price point it would become cost prohibitive for spammers to do on a widespread scale. Spam is dependant on the fact that it costs virtually nothing to send out and therefore they can afford to annoy lots of people with ads that they don't want.

Eliminate captcha, eliminate the lolz.

http://4.bp.blogspot.com/-spJS4HZtDds/TZIdInm5CSI/AAAAAAAAAOk/Mm_i39NH-2I/s1600/funny-captchas.gif

Zomg, recaptcha is pedo

Nice to see at least people go out and steal the idea! lol

http://bitcoincaptcha.org/

Seems to me that a human is not going to be troubled by a 5 second or so lag time to get through a captcha, but a machine which is trying will be.

Why not have the site enterer download a bit of code (with zero effort) which needs to do some bitcoin mining then relinquishes a key proving it has tried before being allowed to proceed.  Once in a blue moon the code will actually hit paydirt (and the site operator becomes a happy camper.)

With such a solution I would welcome multi-threaded robots hammering at my door.

If you havent been spamming other sites before what are the odds you will start spamming sites in future ?

See here for a description of how to use Bitcoin deposits to replace CAPTCHAs in a low trust way:

https://en.bitcoin.it/wiki/Contracts#Example_1:_Providing_a_deposit

Necroing this thread because with bitcoins' growth in popularity this may start becoming relevant.

Also, its not just about captchas... news sites are increasingly requiring login even to +1 or flag a comment; this is a serious PITA!  I'm guessing that's because of spammers as well.


I wonder if you would really need to send a txn.  Imagine a browser plugin that simply signs a message containing the browser's IP address from a bitcoin address that has held X coins for N days (X,N limits can be chosen by each website).  This would limit spammers to relatively few accounts and IP addresses.  These could rapidly be identified, either because there are a lot of IP addresses using the same bitcoin address (spam botnets) or simply by downvotes.

Of course just like with today's captchas a web service is providing this so end sites don't have to worry about bitcoin.  And is gathering spammer data across all sites...

Roughly 80% is still done by specialized scripts developed by the de-captcha service operator, then the 20% that script can not break gets sent to humans in Thailand/Philippines or something, and gets manually broken.

Can your script (or human) crack my proposal?

I think the bitcoin passport/fidelity bond ideas are the best CAPTCHA alternative yet proposed.

This is one use for LBAAT.net. You require a user to send bitcoins to themselves in the future. It is provable that the coins are locked up, and allow access.