Implementation of an intrusion prevention system (IPS) can be a complex process with multiple factors affecting the overall security effectiveness of the solution. These should be considered over the course of the useful life of the solution, and include:
Exploit block rate
Anti-evasion capabilities (resistance to common evasion techniques)
Device stability and reliability
Overall manageability

In order to determine the relative security effectiveness of devices on the market and facilitate accurate product comparisons, NSS Labs has developed a unique metric: Security Effectiveness = Exploit Block Rate x Anti-Evasion Rating x Stability & Reliability By focusing on overall security effectiveness instead of the exploit block rate alone, NSS is able to factor in the ease with which defenses can be bypassed, as well as the reliability of the device.

This report is part of a series of Comparative Analysis Reports (CAR) on security, performance, management, and total cost of ownership (TCO).