Association for Computing Machinery
Denial of Service (DoS henceforth) attack is performed solely with the intention to deny the legitimate users to access services. Since DoS attack is usually performed by means of bots, automated software. These bots send a large number of fake requests to the server which exceeds server buffer capacity which results in DoS attack. In this paper, the authors propose an idea to prevent DoS attack on web-sites which ask for user credentials before it allows them to access resources. Their approach is based on captcha verification. They verify captcha submitted by user before allowing the access to credentials page.