Bitcoin Forum

Notices to EVERYONE who owns a website...

Not for nothing folks, but here's some bad news.  Captcha stops... NO ONE.

Actually thats a lie.

Captcha stops HUMANS...  these things are impossible to read... especially in the wonderful world of SMF Land.

Either use reCaptcha, with their API, or don't bother at all.

and yes... don't believe the hype.. BOTS can decipher captcha,  its just a waste of time and aggrevating for HUMAN users.

Personally, That's your opinion.

Captcha prevents a lot of spam bots, especially when the practice of the captcha is done right where the bot itself cannot read the numbers against the set of the site. (design wise).

I do still believe that ReCaptcha is leaps and bounds better, but any captcha is better than no captcha.

I don't understand why people consider reCaptcha to be so good. Of all captcha variants out there, I think reCaptcha is particularly ANNOYING, and often impossible to read even for humans.

See here: http://www.google.com/recaptcha/demo/ ← refresh a few times and see how often you get unreadable garbage.

Furthermore, it really doesn't help much, since any bot can use services like BypassCaptcha.com or DeathByCaptcha.com which resolve bulk captchas for low fees.

Breaking captcha is a sizable technology hurdle.  Some are trivial to experienced programmers, like methods that don't rotate or shift the characters randomly.

reCaptcha is good because it doesn't generate the images itself, so it isn't predictiable, and is easier to integrate.

I just ask everyone what the color of the sky is...

Should probably change that.  It was meant as a placeholder for a proper spam prevention measure.

recaptcha is very predictable, altho not on the sense you expect. You only need to write down the control word correctly. You can write the other one wrong.
After you see a couple thousand of them you can guess which one is the control word and which one isn't... ;)
And yes, only humans can bypass reCaptcha. Bots don't do so good. But they don't need to do good. 1000 captcha solutions cost $1 after all.

The normal captcha and recaptcha indeed, at least 2 years back it stopped no bots (all these SEO bots like senuke, xrumer etc).
However, when it comes to image guessing it gets a lot tougher as i know.
This: https://nvpn.net/memberss/index.php is very well made i think.

I used to administrate simple phpbb forum for not even a hundred users, it was half-private, but without proper captcha and extra anti-spam measures, it was heaven for spam bots.

You should use image background on phpbb captchas. Also, if you set a password requirement of ppper and lower case letters, numbers and symbols most bots will not be able to register. Even humans get stopped by those password requirements lol

Except it says "click submit" when there is no submit button. :P

Captchas are a necessary evil.
I'd love not to use captchas on CoinAd.com (http://CoinAd.com), but the number of bots is too damn high.

Interesting, thanks for this tidbit.

I don't think it's a waste of time. Is it 100% effective? No. But it will make a HUGE difference in cutting down bot interaction. I think the humans that get frustrated with it is a small price to pay. Having to deal with the mess created by bots causes many more headaches.

I'm a PHP programmer and have also created and hosted many sites, with and without bot prevention measures. Having Captcha definitely helps cut down the spam, false registrations, etc.

It must be your browser setting, bottom line was that i would prefer an image captcha for visitors as well as to prevent bots.

+1, actually.

Sure, captcha can be circumvented.  Does that mean that every bot circumvents it?  No.   Therefore, it cuts down on bots.

I hate reCaptcha too, but the fact is that it works.

The other captchas that people throw together themselves in a weekend, though, those are just embarrassing.

That's a step down. SMF's CAPTCHA is less broken than reCaptcha.

What do I use on my SMF install that makes me so bold as to say that only real humans have an account? Bad Behavior, Stop Spammer (LitecoinTalk has both of these), a reason required on signup, and a super readable CAPTCHA.

no, it is not.

Care to explain?

What are other ways to tell that there is a human or person?

Here are some ideas:

1. Ask questions that can be answered by people relating to current or world events.
2. Ask basic science or math questions.
3. Tell the human to type what he hears (for non deaf humans.) (audio captcha?)
4. Ask about colors or shapes.
5. Ask questions where the answers are about a popular topic of that niche.
6. Use mouse movements?
7. Play a simple game?
8. ?

You have to set a minimum standard also, since captchas can frustrate uneducated people (like those who can't read or spell or think.) but then that depends on your target market. And captchas will frustrate people with accessibility issues.

There are also humans who decrypt captchas for $1 / hour.

Captcha doesn't necessary mean to be garbage text or involve some complex operations.
This one for example is simple yet effective www.1clicaptcha.com

The only reason these haven't been gamed is because nobody uses them. Making a large number of simple problems just makes it tedious. This could be enough for your website though, but if you're unlucky they will become popular and someone will take a weekend off to solve them. You are probably better off making your own simple but original problem and not giving big enough incentive to have it beaten.

No, it's faster to type than spend 20 seconds wondering which to click.

so true,

just yesterday I had to refresh like 20 times because I simply couldn't read the capatcha, so annoying.

There is a game called Text Twist. About 10 years ago it came out. About 10 years ago people were switching from Win 98 to Win XP. About that same time I also made a program in Visual Basic to detect the letters in the game, then type out a few hundred possibilities based on a dictionary.

The game would have been a good CAPTCHA then. But I broke it within a few days. I remember the switch from 98 to XP because my lousy VB program was crashing in 98, and was somehow stable in XP because I kept it running for a few days straight so I can get my name on the all time high score list.

I got the number 1 spot, and then over the years I got beaten by either: more patient human players, or someone else made a robot to do the game for them.

It's not really that difficult to look at it for a mere 5 seconds to just pick out of the small list which doesn't fit.

I believe we had these in high school. :P

I also think that Captchas are really annoying. For smaller niche websites, some JavaScript/CSS trickery, honeypot fields or Askimet (http://en.wikipedia.org/wiki/Askimet) should suffice.

The least annoying captchas imho are the ones that are very easy to read/short while slightly animated.

They're very seldom, and almost fun to do.

Totally agree.  If you don't have bots or other controls on your own server analyzing content for spam, then you're either giving the advantage to those who use bots against your on your own site, or you're royally pissing off your users.


Here's such an example: http://decaptcher.org/

It's not a waste of time.

1) It raises the bar, deterring simple bots.  Even a bot with access to a mechanical turk will likely have to pay for said access.

2) It reads books, doing a better job than OCR.

Install any cms, pull together a few pages of info then shut off any and all spam prevention. I matter of days you will begin to see why It's worth it.

I tested this once, what seemed to.amaze me the most was the type of botting used to spam. with no prevention you get hit by bots that are so outdated in there tactics that It's clearly a child or a total noob running said bot.

I noticed three levels of spam bots when I ran my test... as said total noob bots that pasted just a link and had names consisting of random characters. level two was the fake viagra and porn spam style bots. a little text of jargon more defined user name and ofcourse a link. level three was what we see today with the nonsence paragraphs a legitimate looking user name and links.

Also keep in mind spammers are all over the world.. so times the above by an unknown world wide number... after about a month. your cms will look like matrix code.

Bottom line is captcha annoying? sure is... is it needed? sure is...

Would it not be a good idea to replace Captchas with small Bitcoin payments? Less annoying and actually gets the spammers to hand over some money. Possibly make it an alternative and see which people choose.

That would be a terrible idea, unless it's a very Bitcoin-specific site.

I run a forum system and do something similar. There is a clock captcha (what time is it?) and a simple question. Since ditching "normal" captchas and moving to clock+easy question, I've had no problem with bots or spammers.

I was more thinking of this site. But it might work well as an either/or proposition on other sites. Of course, before long, it wouldn't be bitcoins just for registration but bitcoins for everything.

Though for some sites, that wouldn't be so bad.

It'd be bad even for this site though.  What do you think the percentage of people who come here are brand new to Bitcoin, and haven't even figured out how to buy any yet?  Even if it's a token amount, it would still keep a vast majority of the currently-registering newbies away from the forum.

Now, if that's the goal of the forum, then sure, I can understand it.  Otherwise.... no.

Lets say hypothetically you wanted to make 200 accounts one a forum that had a captcha.

What would stop you from making a web page that displays a captcha to a user and gives them .01BTC for each one they solve? This website would be relaying the challenge the forum gives to a real person an pay them about 12 cents to solve it, then pass the answer to the forum.

This can also be done with porn, show a different picture each time they solve a captcha.

I believe this is how it is done.

In such a scenario, captcha codes and all are nothing but a total waste of time

Why did you bump this? Are you a spammer?

Captcha is NOT a waste of time. Before I didn't use captcha I have many problems with some strange inputs. After I start use it is everthing gone and it is OK.
So Captcha IS OK.