. Intrusion Prevention Service (IPS) is a fully integrated security subscription for all WatchGuard Firebox M400 appliances. It works in tandem with the application layer content inspection of the WatchGuard Firebox M400 to provide real-time protection against network threats including spyware SQL injections cross-site scripting and buffer overflows. IPS scans traffic on all major protocols using continually updated signatures to detect and block all types of threats. And because IPS is integrated with WatchGuard Firebox M400 security appliances you have an easy-to-manage cost-effective solution without additional hardware to purchase and maintain..