Research and implementation of CAPTCHA based on Ajax

Abstract

Currently, most authentication system requires users to answer the CAPTCHA (Completely Automated Public Turing Test to Tell Computer and Human Apart) before gaining the system access. CAPTCHA is a standard security technology for distinguish between human and computer program automatically. This paper describes the Ajax technology and its advantages of web interactivity and efficiency of the user to enter the CAPTCHA may appear misjudgment the inconvenience. Designed Ajax-based CAPTCHA scheme which can prompt the user input of right or wrong. This scheme using the characteristics of Ajax technology asynchronous transmission, after the user input CAPTCHA, immediately the prompt of entry correct or not gave. Greatly increase the website interactivity, improve the user experience, not only ensure the user security, but also improve software friendly degree. © Springer-Verlag Berlin Heidelberg 2013.