Turbo ACLs

Turbo ACLs are a feature implemented in the Cisco 7200 and 7500 series routers and Cisco 12000 series gigabit switch routers. They evaluate ACLs for more expedient packet classification and access checks. PIX Firewall also supports turbo ACLs starting in version 6.2. Turbo ACLs are a mechanism to get around the performance problems caused by normal ACLs, which are searched sequentially until a match is found. This kind of processing not only can create excessive overhead for the CPU, but also introduces an element of uncertainty in the router's performance, because the depth at which an access list element gets hit is uncertain.

The turbo ACL feature compiles the ACL ACEs into a set of special lookup tables while maintaining the first-match ...

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