Re: MAC Address

[Leo Razoumov <slonik.az@...>]

On Sun, Feb 13, 2011 at 05:37, Axel Kittenberger <axkibe@gmail.com> wrote:
> MAC is someting ethernet specific, not every network interface has to
> have one. Correct me if I'm wrong, but why should a PPP-connection
> have a mac adress anyway? Its a point-to-point connection, no need to
> address something on Layer 2 in the OSI Modell where Mac belongs to.
>
> Also not every computer must have a "default network interface", what
> if you are not connected to the internet and thus not have a default
> route? Or you are part of the backbone? (unlikely but possible :-)
>
> I wonder what the usecase is that warrents wanting to know "mac of the
> default network interface"?
>

I do not think that there is a universal definition of the "default
NIC interface" because its meaning depends on interpretation of the
word 'default' in this context. For the sake of sending/receiving IP
packets it is natural to assume 'default' being associated with a
default route.

On the other hand, for the sake of unique machine identification (e.g.
proprietary license code generation)  you might consider the first
Ethernet MAC.  Do 'ifconfig -a' if on UNIX and pick the NIC you like.

--Leo--