WHAT IS WEB APPLICATION FIREWALL?
A web application firewall (WAF) is a network defense that filters, monitors, and blocks HTTP traffic to and from a web application. Unlike a regular firewall that serves as a safety gate between servers, a WAF is able to watch application-level traffic and decide to allow or disallow based on the data that is visible over the network. WAF security typically performs SSL termination to watch decrypted traffic for pattern-matching or volumetric attacks. Organizations often deploy WAFs to detect and block these types of network attacks, integrating them with defenses that see data closer in to the application.
WAFs may come in the form of an appliance, a server plugin, a filter, or a WAF operated by a cloud or service provider. Web application firewalls can be customized to an application, but the effort to perform this customization can be significant and needs to be maintained as the application is modified. The ideal solution is one that provides continuous visibility, application intelligence, and very rapid response.