US Patent 7957311 Programmable hardware-based traffic policing

A hardware-based technique for policing traffic in a network node involves programming a set of algorithm-specific policing primitives that establishes a relationship between condition primitives and action primitives and populating a searchable memory with a set of indexed action primitives. Action primitives are then selected from the searchable memory in response to condition primitives related to a received datagram. Policing actions related to the datagram are performed in response to the action primitive. Because the algorithm-specific policing primitives are programmable, a network node can be adapted to implement a wide variety of policing algorithms. Additionally, multiple different policing algorithms can be implemented in hardware without the need for a different set of combinational logic for each different policing algorithm.