The access control list (ACL) daughter cards for the Catalyst 8540 are ideal for supporting high-speed Layer-3 Gigabit backbone applications that require Layer 3 Security Capabilities. The ACL Daughter Cards are supported by the Catalyst 8540 platform, providing large enterprises and service providers with both Layer 3 and ATM switching in one integrated platform.The ACL daughter cards implement data-plane access lists in hardware, providing high-speed performance. This extends the traffic control and security capabilities of the Catalyst 8540 beyond control-plane access lists, which are currently supported. The ACL daughter card can be used to limit/grant access to certain network resources by filtering traffic based on the Layer 3 header. It is designed specifically to meet the demanding needs of large enterprise and service provider networks.