[nfbcs] Text Captcha

[Peter Donahue]

Good afternoon everyone,

    Jus thought I would share this with you all concerning a captcha service 
I stumbled on when registering for a blog for one of the radio programs we 
listen to on Sunday Morning. Here is the information taken from the Text 
Captcha Home Page:

>From the Web Site:

Text CAPTCHA Logic Questions
A CAPTCHA is a test to tell humans and robots apart. You've probably used 
one before: identifying a string of letters from an image to show that you 
are human, rather than a "bot". This site provides a web service to generate 
textual CAPTCHAs based on simple logic questions.

Seventeen, seventeen, twenty five and forty: the 2nd number is?

Do you really need a CAPTCHA?
A CAPTCHA is disruptive to the user experience, adding an extra task to the 
process you want to protect. In the majority of cases, a CAPTCHA is 
overkill. For example, if you want to protect a comment form from spam there 
are plenty of tricks to try first.

Do text CAPTCHAs actually work?
Yes, and No.

A text CAPTCHA is more accessible to visually impaired users than their 
image-based alternatives. To defeat OCR scanning, image CAPTCHAs have to 
distort the letters used, and they can be tricky to decipher!

The problem with text CAPTCHAs is that they provide inherently more 
information than a distorted image. They are parseable, under the right 
conditions solveable. With the advent of contextual parsing tools such as 
Wolfram Alpha, such simple logic puzzles have become easier to solve 
programatically.

What is textCAPTCHA?
This site provides a simple web service to generate text-based CAPTCHAs, 
examples of which are on the demo page. If you wish to use them, find out 
how the service works, and sign up for your own account.

Questions? Contact Rob.



Peter Donahue





Peter Donahue

 “No weapon that is formed against thee shall prosper.”
Isaiah 54:17

 “While for our princes they prepare
In caverns deep a burning snare,
He shot from heaven a piercing ray,
And the dark treachery brought to day.”
Anonymous