摘要 |
A network switch, configured for performing layer 2 and layer 3 switching in an Ethernet (IEEE 802.3) network without blocking of incoming data packets, includes network switch ports, each including a policy filter configured for obtaining layer 3 and layer 4 information from a received layer 2 frame. The layer 3 information and the layer 4 information are used to determine a policy identifier that specifies a layer 3 switching operation to be performed on the received layer 2 frame. Each network switch port also includes a policy cache that caches portions of the layer 3 information and the corresponding policy identifier. The policy filter and the policy cache are then simultaneously searched for subsequent layer 3 frames to find the appropriate policy; if the appropriate policy is located in the policy cache, the searching operation is completed, enabling the network switch port resources to begin searching operations for another packet. Hence, policy search performance can be improved by execution of simultaneous search operations in the policy filter and the policy cache.
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