To defend against DDoS attacks, your Barracuda Web Application Firewall communicates with Barracuda Active DDoS Prevention servers in the Barracuda Cloud Scrubbing Centers. This communication allows your Barracuda Web Application Firewall to feed information about attacks back to the Barracuda Cloud Scrubbing Center, where the attacks are blocked. It also allows the Cloud Scrubbing Center to optimize DDoS settings when your application is under attack.
To allow this connectivity, ensure that your Barracuda Web Application Firewall is allowed to connect to the following IP addresses:
on these TCP ports: