A data link layer switch includes a switching mechanism coupled to a plurality of port interface controllers. Each of the port interface controllers comprises a multicast address table, a multicast matcher, and a timer. The multicast address table stores multicast addresses for hosts attached to the port interface controller. The multicast matcher matches an incoming packet to a target pattern, generates a multicast address from the incoming packet if the incoming packet matches the target pattern, and stores the generated multicast address in the multicast address table. The timer determines an amount of time that the generated multicast address remains in the multicast address table.