Draytek Vigor2820 Series User Manual page 110

Strict Security Checking - All the packets, while transmitting
through Vigor router, will be filtered by firewall settings
configured by Vigor router. When the resource is inadequate, the
packets will be blocked if Strict Security Checking is enabled. If
Strict Security Checking is not enabled, then the packets will pass
through the router.
Vigor2820 Series User's Guide
100