Collection of Free Captcha’s for your Website and more about security
In today’s article I will tell you about methods of protection against rotots. Just imaging – you created some post form at your website (to accept new articles, comments). And, what will happen if we don`t will add any protection here. As minimum our website will attached with big amount of robots. They will try to post different unwanted content (back links to another websites). As maximum – your website can be hacked. So, always (I repeating – always) checking all income variable before working with them. Make its safe.
So, as I promised – today I will make review of captcha services and methods
reCAPTCHA is a free CAPTCHA service that helps to digitize books, newspapers and old time radio shows
Free service too. A CAPTCHA image shows a random string which the user has to type to submit a form. This is a simple problem for (seeing) humans, but a very hard problem for computers which have to use character recognition, especially, because the displayed string is alienated in a way, which makes it very hard for a computer to decode
Protect your guestbook, feedback form, comment form and any other web form with free anti-spam service of verification urls.
BotDetect is unique among Captcha solutions in offering many Captcha image and sound styles. While each of them is easily comprehensible to human users, randomly using multiple Captcha generation algorithms makes the Captcha challenge practically impossible to pass automatically.
5. Securimage PHP Captcha
Free and open source project, but unfortunately it not worked today. Hope that they will back soon.
Cryptographp is a PHP script for generate captchas. Cryptographp limit the robots bombarding spams and automating the forms: spaces members subscriptions, guestbooks, forums… This script is free and does not use any database.
Free Classic ASP Security Image Generator (CAPTCHA) Script
Captcha.cc’s free service makes it extremely simple to place very hard captcha images in front of a form submission. These images are easy for humans to read, but very hard for computers to read. This cuts down on spam for blog comments, contact form submissions and much more.
OpenCaptcha: The Free & Open Captcha Web Service
10. Web Wiz CAPTCHA
Web Wiz CAPTCHA is free security image software written in ASP that displays a security image on your websites forms which only humans can read. This prevents your websites forms from being spammed by robots and hacked using dictionary or brute force hacking.
WebSpamProtect.com allows you to instantly add verification image (CAPTCHA) to your web site and protect your forms against spam robots.
This form processor (or form-to-email script) is intended to collect data from an HTML form and send it to a specified email address. It works with any kind of HTML forms and you can use it multiple times on your pages.
13. Captcha ASP script
The main idea of a Captcha test (completely automated public Turing test to tell computers and humans apart) is to prevent automated form submission. This project is a very short VB Script source code, which let’s you generate gif, jpg or png images with text which most people can easily read and enter to a form field, but automated computer program cannot.
14. Floresense’s Captcha control
Floresense’s Captcha control is a flexible, multi-option captcha control for .NET
16. Text Disguise
Simply put, Text Disguise is a Human Interactive Proof. What is a Human Interactive Proof? It is a method of telling human users apart from computers (or, also known as “bots”). By presenting a CAPTCHA-image to a user, it requires that a living, breathing, thinking person be at the keyboard – interacting with your web site.
And this is not all, image and graphic captcha’s is good of course. But more human methods can be very useful too, as example:
* math captcha 1, * math captcha 2
* logic text captcha, so you even can ask something and await correct answer
* video captcha – this is new great methods
Commonly, what else? Any what you can imagine – some photo-based toys, any games, sound-based, all what can separate human and machine!. Hope today’s article was interested.