Provided by: The International Journals of Engineering & Sciences (IJENS)
Topic: Enterprise Software
Date Added: Oct 2011
Now-a-days, due to enormous growth of web users many services in the internet including e-mail, search engine and social networking are provided with free of charge. With the expansion of Web services, Denial of Service (DoS) attacks by malicious automated programs (e.g., web-bots) is becoming a serious problem of web service accounts. CAPTCHA (Completely Automated Public Turing test to tell Computers and Humans Apart) is a human authentication mechanism that generates and grades tests to determine whether the user is a human or a malicious computer program.