Access control lists (ACLs) define how traffic is to be handled as it passes through a network device.
ACLs use addressing and port information to control conversations.
ACLs are typically implemented in routers, but new hardware allow Layer 2 and Layer 3 switches to consult the list before passing the packet.
ACLs enable users to configure any switch to control traffic based on Layer 3 and above of the OSI reference model.
These ACLs are mapped to a VLAN or a Layer 2 port to control traffic flows.
VACLs are controlled in hardware and are not supported on all platforms.
Currently VACLs are supported on the 6000 (with a Policy Feature Card [PFC] or PFC2), the 3550, and the 2950 series switches.
The VLAN ACL (VACL) is ...