A method of forwarding data in a network switch fabric is disclosed. An
incoming data packet is received at a first port of the fabric and a
first packet portion, less than a full packet length, is read to
determine particular packet information including an opcode value. The
opcode value allows the fabric to determine the packet type, such a a
whether the packet is a broadcast packet, a unicast packet, a multicast
packet, etc. Based on the opcode value read, a particular forwarding
table of a plurality forwarding tables is read and an egress port bitmap
is determined based on entries read from the particular forwarding table.
The incoming data packet is then forwarded based on the egress port
bitmap. In addition, the architecture of the switch fabric is also
disclosed.