forwarding

• Russ's course on OrhanErgun
• FE = Forwarding Engine
• phy chip - rx ring - [iq (input queue)] - fe - [oq] - tx ring - phy
• iq and oq necessary for qos
• copying data is expensive and slow, pointers are better
• routers rewrite L2 headers and separate broadcast domains
• fpga = field programmable gate array
• asic = application specific integrated circuit
• even when there's no data travelling on the wire, there is still electrical carrier signal