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RE: Captcha and inaccessiblity

From: Geoff Deering <gdeering@acslink.net.au>
Date: Mon, 20 Oct 2003 08:39:38 +1000
To: "Charles McCathieNevile" <charles@w3.org>, "Tom Croucher" <tcroucher@netalleynetworks.com>
Cc: <w3c-wai-gl@w3.org>
Message-ID: <NBBBJPNFCLNLAADCLFJBIELNFBAA.gdeering@acslink.net.au>

I think there is a need for a "Techniques for Accessible Form Handling"
document or the like so that developers are given viable alternatives to
prevent machine spamming of forms.  The WAIGL at least has to show that it
is aware of such needs and issues and offer viable means to address them.  I
think the question is a viable alternative, it's just that the distorted
image has become a default because it is easy to generate with various
libraries and match the answer on the backend.

At the same time a lot of spamming can be blocked by proper server
management of matching IPs against attempts to spam and blocking their
access.  It too is not foolproof, and can have problems if not managed
intelligently, but at the same time, it's more efficient and effective than
not at all, but you can still build a register of spamming machine IP and
firewall them from your server.  But you still need the captcha strategies
on the forms for spamming robots on dynamic IPs.


-----Original Message-----
From: Charles McCathieNevile

On Sat, 18 Oct 2003, Tom Croucher wrote:

>A couple of points, firstly yes it might be inaccessible but I am trying to
>be pragmatic. If we can help find soltuions and offer advice to companies
>that feel they need this feature that can only help. Companies for example
>could argue that it is uneconomic to not use captchas. How many of use have
>recieved spam from yahoo or hotmail or aol addresses. Yahoo uses captchas
>to attempt to address this issue.

Sorry, I am not arguing that reducing spam is bad thing. It would be helpful
to work out how to do something like this, but my point was that even having
the options of image and audio would still lead to problems - and that if
that is the case it should automatically follow that such a solution could
not pass the guidelines.

I think it is generally known that I think any kind of exception to the
guidelines based on something other than accessibility is a huge mistake.

I think your idea of questions can help provide alternatives. I disagree
text is universally accessible - it is a requirement of anything universally
accessible that it be available as text, but that's not enough as a rule.
being able to put it in ways that are hard to automatically treat can help
for a while.

by the way there is a theory in security, which basically says that club
locks won't work because everyone will need to get one before they stop
people from stealing cars, whereas car locator beacons work because even
though you can steal the car you will get caught. Stopping people sending
spam through yahoo is like buying club locks - it means those who don't do
similarly will be better targets for spammers...


Received on Sunday, 19 October 2003 18:39:58 UTC

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