Patent US 7,983,283

A packet routing apparatus has a plurality of routing units, connected by a first connecting mechanism. The plurality of routing units comprise a first routing unit, connected to at least one port, and a second routing unit, connected to an extended function processor. The first routing unit transmits a packet, received from the port, to another first routing unit and/or a second routing unit. The second routing unit transmits the packet, received from the first connecting mechanism, to the extended function processor.