Design of Accented Character-based CAPTCHA with Usability Test for Online Transactions

Abstract

Websites serve as the primary interface on the Internet for transactions such as subscription, downloads, database access and storage. Websites are however, sources of security breaches to information systems that are attached to them. Several techniques have been developed to provide security on websites such as secured socket layer (ssl) and CAPTCHA systems. CAPTCHA is an authentication system for verifying human identity during online transactions. Text, mathematical operations, images and audio have been used to develop CAPTCHA systems. The basis of each system has been limited thus leading to successful attacks and compromised systems. In this work, the aim is to integrate accented characters into the CAPTCHA code generation mechanism and test the usability of the developed system on a website. The results indicate successful generation and user acceptability.