Access Control List is an advanced feature of the switch, it allows network administrators to configure the switch to examine packet formats and content from Layer 2, Layer 3, or Layer 4 (also known as the MAC, IP and TCP/UDP layers). UniFi switches have Access Control Lists (ACLs), useful for isolating device traffic on the same VLAN. Networks with high-performance requirements can also use them to manage inter-VLAN routing, rather than rely on a gateway or firewall. When the switch determines that an ACL applies to a packet, it tests the packet against the conditions of all rules. After these layer parameters are defined and detected, the.