ethwireck can detect if the physical layer of the
Ethernet is up. Laptops which use dynamic IP
address assignment via DHCP have the problem that
the boot process is much longer when no wire is
connected to the Ethernet card. This is because
the startup scripts have to wait for the DHCP
request to time out. ethwireck can be used in the
init script for your network card to determine
whether or not an interface should be brought up.
In other words, a timeout is avoided.
