Just to follow up on what Phoneboy said, the Performance Impact rating specifies how enabling that particular signature will impact SecureXL acceleration on the firewall. Here is a rough guide taken my my IPS Immersion self-guided video series:
The Performance Impact rating specifies the level of CPU processing overhead for the gateway enforcing this protection. Gaia embedded appliances (models 1200R–1500) or smaller Check Point gateway appliances will be much more heavily impacted by High and Critical–level IPS Protections than larger gateways.
• Critical – 100% of traffic subject to inspection by this Protection is ineligible for acceleration by SecureXL and will take the slowpath (F2F) through a R80.10 or earlier gateway. (We will cover IPS performance extensively in Module 10)
• High – Traffic inspected by this Protection will be inspected ~50% in the non–accelerated slowpath (F2F) and CPASXL path, and ~50% in the partially–accelerated Medium Path (PXL).
• Medium – 100% of traffic subject to inspection by this Protection will be handled in the partially–accelerated Medium Path (PXL) on the gateway.
• Very Low/Low – Protection is fully accelerated in the fastpath by SecureXL.
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