take ownership of the packet, rather than doing so only if they return
success. This breaks semantic compatibility with Linux's
hard_start_xmit() method, but means that we don't have to worry so much
about error cases.
Split mechanism of processing received packets (net_rx_process()) out
from policy (net_step()), preparatory to putting net_step() in a separate
object.
implementation allows for only one, and does so without compromising on
the efficiency of static allocation).
Link-layer protocols are cleanly separated from the device drivers.
Network-layer protocols are cleanly separated from individual network
devices.
Link-layer and network-layer protocols are cleanly separated from each
other.
