Abstract: A packet classifier having a forest of hash tables data structure. The forest of hash tables data structure includes a number of hash tables, each hash table having a bit mask corresponding to an equivalent set of rules. Each hash table includes a number of entries, wherein an entry of a hash table may correspond to a rule. One or more of the hash tables may include a marker in one entry, wherein the marker identifies another one of the hash tables. The hash table identified by the marker is a descendant of the hash table in which the marker is placed.

Abstract: A method and apparatus for use with a computer system are disclosed. A packet is received that includes a header. The header indicates at least one characteristic that is associated with a layer of a protocol stack, and the layer is hierarchically no lower than a network layer. The packet is parsed in hardware to extract the characteristic(s), and the packet is processed based on the parsing. The computer system may be capable of executing software of a protocol stack to extract the characteristic(s) of the packet, and the apparatus may include an interface and a circuit. The interface may be adapted to receive the packet, and the circuit may be adapted to parse the header to extract the characteristic(s) without causing the computer to execute the software and process the packet based on the extracted characteristic(s).

Abstract: According to some embodiments, routing information for an information packet is determined in accordance with a destination address and a device address.