期刊名称：International Journal of Computer Science Issues
印刷版ISSN：1694-0784
电子版ISSN：1694-0814
出版年度：2011
卷号：8
期号：6
出版社：IJCSI Press
摘要：Recently web services have become an important business tool in e-commerce. The emergence of intelligent, sophisticated attacks like DoS makes web services more vulnerable than ever. One of the most common attacks against web services is a denial of service attack. To mitigate the Dos attack, CAPTCHA is used as one of the standard security technology. CAPTCHAs generate and grade tests that most humans can pass but current computer programs cant. Such tests often called CAPTCHA challenges are based on hard, open artificial intelligence problems. During past years, many researchers worked on HIP and CAPTCHA systems. This paper is a collection of 179 published works on HIP and CAPTCHA. CAPTCHA scheme, attacks and analysis, applications, usability issues and recaptcha are the heads under which the papers have been categorised. We hope that this paper would help new researchers in CAPTCHA domain to quickly find the works that are done previously.
