Any good CAPTCHA to recommend?

[Francois Bonzon]

After a Google search, I see that quite a few CAPTCHA implementations
in PHP are available. I'd like one that's not (easily) OCR-able, or
otherwise crackable. Open source or commercial is not important. Any
recommendations , or experience with a specific one to share?

I get a lot of SPAM entries on a guestbook, and want to protect it.
I'll require users to solve a CAPTCHA before their entry is accepted. I
might use CAPTCHAs to protect other form submissions, though.

[elyob]

Re: Any good CAPTCHA to recommend?


"Francois Bonzon" <NOSPAM.francoi s@bonzon.com> wrote in message
news:1150326977 _591@sicinfo3.e pfl.ch...[color=blue]
> After a Google search, I see that quite a few CAPTCHA implementations in
> PHP are available. I'd like one that's not (easily) OCR-able, or otherwise
> crackable. Open source or commercial is not important. Any
> recommendations , or experience with a specific one to share?
>
> I get a lot of SPAM entries on a guestbook, and want to protect it. I'll
> require users to solve a CAPTCHA before their entry is accepted. I might
> use CAPTCHAs to protect other form submissions, though.
>[/color]

My experience is that CAPTCHA doesn't work.

I get lots of spam though.

:(

[the DtTvB]

Re: Any good CAPTCHA to recommend?

http://en.wikipedia.org/wiki/CAPTCHA#PHP

[Toby Inkster]

Re: Any good CAPTCHA to recommend?

Francois Bonzon wrote:
[color=blue]
> I get a lot of SPAM entries on a guestbook, and want to protect it.
> I'll require users to solve a CAPTCHA before their entry is accepted. I
> might use CAPTCHAs to protect other form submissions, though.[/color]

Don't use CAPTCHA. Make users sign up to your service and check their
e-mail address is valid. CAPTCHA is inaccessible and not cross-browser
compatible.

--
Toby A Inkster BSc (Hons) ARCS
Contact Me ~ http://tobyinkster.co.uk/contact

[Rik]

Re: Any good CAPTCHA to recommend?

Toby Inkster wrote:[color=blue]
> Francois Bonzon wrote:
>[color=green]
>> I get a lot of SPAM entries on a guestbook, and want to protect it.
>> I'll require users to solve a CAPTCHA before their entry is
>> accepted. I might use CAPTCHAs to protect other form submissions,
>> though.[/color]
>
> Don't use CAPTCHA. Make users sign up to your service and check their
> e-mail address is valid. CAPTCHA is inaccessible and not cross-browser
> compatible.[/color]

CAPTCHA isn't a specific method.... I'm sure there are accessable,
cross-browser CAPTCHA methods.

Grtz,
--
Rik Wasmus

[Paul Lautman]

Re: Any good CAPTCHA to recommend?

Francois Bonzon wrote:[color=blue]
> After a Google search, I see that quite a few CAPTCHA implementations
> in PHP are available. I'd like one that's not (easily) OCR-able, or
> otherwise crackable. Open source or commercial is not important. Any
> recommendations , or experience with a specific one to share?
>
> I get a lot of SPAM entries on a guestbook, and want to protect it.
> I'll require users to solve a CAPTCHA before their entry is accepted.
> I might use CAPTCHAs to protect other form submissions, though.[/color]

Take a look at www.phpclasses.org, there's a good one gone up there
recently

[totalstranger]

Re: Any good CAPTCHA to recommend?

On or about 6/15/2006 2:27 AM, it came to pass that Toby Inkster wrote:[color=blue]
> Francois Bonzon wrote:
>[color=green]
>> I get a lot of SPAM entries on a guestbook, and want to protect it.
>> I'll require users to solve a CAPTCHA before their entry is accepted. I
>> might use CAPTCHAs to protect other form submissions, though.[/color]
>
> Don't use CAPTCHA. Make users sign up to your service and check their
> e-mail address is valid. CAPTCHA is inaccessible and not cross-browser
> compatible.
>[/color]
CAPTCHA works well at stopping most robots and hackers from using online
contact and signup forms. The version I use from
http://freshmeat.net/p/captchaphp (with some modifications and a fix or
two) works well and provides for all browsers, including IE where
external image files are required. My attempts at using embedded images
with IE7 in strict mode were futile, although embedded images work with
most other modern browsers.

I do agree that validation of the email address and it's verification
using checkdnsrr($dom ain, 'MX') is required.

[AlexVN]

Re: Any good CAPTCHA to recommend?

Hi,

I've used PhpCaptcha by http://www.ejeliot.com/. It looks Ok for me.

--
Sincerely,
Alexander

http://www.alexatnet.com/

Francois Bonzon wrote:[color=blue]
> After a Google search, I see that quite a few CAPTCHA implementations
> in PHP are available. I'd like one that's not (easily) OCR-able, or
> otherwise crackable. Open source or commercial is not important. Any
> recommendations , or experience with a specific one to share?
>
> I get a lot of SPAM entries on a guestbook, and want to protect it.
> I'll require users to solve a CAPTCHA before their entry is accepted. I
> might use CAPTCHAs to protect other form submissions, though.[/color]

[arclight]

Re: Any good CAPTCHA to recommend?


Toby Inkster wrote:[color=blue]
> Francois Bonzon wrote:
>[color=green]
> > I get a lot of SPAM entries on a guestbook, and want to protect it.
> > I'll require users to solve a CAPTCHA before their entry is accepted. I
> > might use CAPTCHAs to protect other form submissions, though.[/color]
>
> Don't use CAPTCHA. Make users sign up to your service and check their
> e-mail address is valid. CAPTCHA is inaccessible and not cross-browser
> compatible.[/color]

I've written an accessible alternative to the typical graphics based
CAPTCHA, which will work in any web browser, including lynx, you can
get it at http://system-x.info/?pageid=18&menutree=47

[Toby Inkster]

Re: Any good CAPTCHA to recommend?

Rik wrote:
[color=blue]
> CAPTCHA isn't a specific method.... I'm sure there are accessable,
> cross-browser CAPTCHA methods.[/color]

Thre aren't.

--
Toby A Inkster BSc (Hons) ARCS
Contact Me ~ http://tobyinkster.co.uk/contact

[Geoff Berrow]

Re: Any good CAPTCHA to recommend?

Message-ID: <1150379516.160 548.283540@r2g2 000cwb.googlegr oups.com> from
arclight contained the following:
[color=blue]
>
>I've written an accessible alternative to the typical graphics based
>CAPTCHA, which will work in any web browser, including lynx, you can
>get it at http://system-x.info/?pageid=18&menutree=47[/color]

Ahem...

"...click here for an example...."

--
Geoff Berrow (put thecat out to email)
It's only Usenet, no one dies.
My opinions, not the committee's, mine.
Simple RFDs http://www.ckdog.co.uk/rfdmaker/

[blank@email.com]

Re: Any good CAPTCHA to recommend?

In article <1150326977_591 @sicinfo3.epfl. ch>, NOSPAM.francois @bonzon.com
says...[color=blue]
> I get a lot of SPAM entries on a guestbook, and want to protect it.
> I'll require users to solve a CAPTCHA before their entry is accepted. I
> might use CAPTCHAs to protect other form submissions, though.
>
>[/color]

I'd suggest using CAPTCHA is a great way to ensure you end up with an
empty guestbook and very few return visitors.

[R. Rajesh Jeba Anbiah]

Re: Any good CAPTCHA to recommend?

arclight wrote:
<snip>[color=blue]
> I've written an accessible alternative to the typical graphics based
> CAPTCHA, which will work in any web browser, including lynx, you can
> get it at http://system-x.info/?pageid=18&menutree=47[/color]

Having written couple of bots, I would say this is Ok, especially
when you don't have GD--but stilll very easy to hack:
1. The bot first see the question and it logs the question so that
the person who runs the bot will add the answer to it's (bot's) list
2. Next time bot sees the same question, and it answers from it's
list; otherwise go to step 1

For helping blind people, it is worth to add sound files as in
e-gold.com; the implementation is also easy as creating WAV files on
the fly is extremely easy with PHP.

--
<?php echo 'Just another PHP saint'; ?>
Email: rrjanbiah-at-Y!com Blog: http://rajeshanbiah.blogspot.com/