Web Application Firewalls Overview
What are Web Application Firewalls (WAFs)?
Web Application Firewall (WAF) Features & Capabilities
WAFs protect web applications against threats such as:
Denial of service
WAFs generally present the following features:
Libraries of attack data based on known attacks to web applications
Monitoring, filtering and blocking of data and access to web applications
Automated attack detection, both identity-based (e.g. dynamic whitelisting, fingerprinting, risk scoring) and behavioral (e.g. risk scoring)
Advanced security techniques (e.g. deception/misdirection, virtual patch deployment, honeypot)
Zero-day attack prevention (related to the above)
A management interface with alert system
Reporting and analytics on threat and application usage
The cost of web application firewalls depends on deployment. There are three options:
A managed service or cloud-hosted WAF delivered as part of a subscription. This can be relatively low overhead as part of a larger subscription (e.g. part of a CDN). But it also may contain unneeded features.
A network-based appliance. This presents relatively high overhead but reduces latency because it is installed locally and close to the application.
A host-based WAF residing in the application’s code. This is rarer and may present less desirable computing costs and greater maintenance.