Web Applications security has become progressively more important these days. Enormous numbers of attacks are being deployed on the web application layer. Due to dramatic increase in Web applications, security gets vulnerable to variety of threats. Most of these attacks are targeted towards the web application layer and network firewall alone cannot prevent these kinds of attacks. The basic reason behind success of these attacks is the ignorance of application developers while writing the web applications and the vulnerabilities in the existing technologies. Web application attacks are the latest trend and hackers are trying to exploit the web application using different techniques. Various solutions are available as open source and in commercial market. But the selection of suitable solution for the security of the organizational systems is a major issue. This survey paper compared the Web Application Firewall (WAF) solutions with important features necessary for the security at application layer. Critical analysis on WAF solutions is helpful for the users to select the most suitable solution to their environments.