TreeCAM: Decoupling Updates and Lookups in Packet Classification
Packet classification involves determining the highest-priority rule to which each network packet matches out of a set of rules (i.e., a classifier). Each rule specifies a desired action on matching packets identified by a combination of the packet fields (e.g., source/destination IP, source/destination port, and protocol). Packet classification is vital for QoS, security, and traffic monitoring and analysis. While line rates continue to improve, classifiers also grow in size due to rule customization for Virtual Private Networks (VPNs) and Quality of Service (QoS). Thus, larger classifiers need to be searched at higher rates (e.g., several tens of thousands of rules every few nanoseconds).