Using Integer Multiplication to Protect Web Forms with Ajax

Introduction

Now that you've been introduced to the main subject of this series of articles, it's time to recall the topics we discussed in the last article. In that tutorial I went through the development of a simple Ajax-based application that could dynamically generate a bunch of elementary addition problems to be displayed within a targeted web form.

The logic that drove this approach was quite easy to understand.Each time a user attempted to submit an HTML form, they were asked to enter the correct sum, in this way implementing a basic mechanism aimed at making the form in question more secure against spam web bots and other malicious programs.

Of course, using this approach doesn't mean that a web form will be completely invulnerable to those attacks. However, its simplicity and minimal requirements turn it into a viable option for making an online form slightly more secure.

Now that you've recalled how to develop an Ajax-driven program to generate dynamic sums as challenge strings, you might like to hear that the concept can be extended to work with other mathematical operations as well. Therefore, in this third installment of the series, I'll be explaining how to build a web form protection system where users will be asked to multiply two integers before submitting the form in question.

This is a variation of the example created in the preceding article, but it does deserve a closer look. So start reading now!