Re: Question about ethernet addresses



On Mon, 29 Sep 2008 20:33:25 -0400, Frank J Warner wrote
(in article <290920081733251453%warnerf@xxxxxxxxxxxxxxxxxxxxxx>):

Hoping one of you sharp IT guys can answer a question about ethernet
addresses on my Mac. So far, I seem to be coming up with two different
addresses for a single machine, and I wonder which one is lying to me.

Running System Profiler yields the following for my G5's MAC address
under ethernet settings:
00:18:24:2a:b3:f4

Opening the Network pane of my System Preferences gives me a completely
different ethernet address:
00:0a:93:45:b1:14

(The two examples above have been munged in case hackers find these
addresses useful, but the differences are more or less as written.)

My understanding is that the ethernet address is a unique identifier
for my network card. If that's the case, why are two different system
tools reporting two different addresses, and which one is accurate?

You have two different MAC addresses, possibly one Ethernet and one wireless,
or you have two Ethernet cards. You should note that if your Bluetooth system
is set up as a PAN (Personal Area Network) which is common if you have some
Bluetooth-enabled cell phones (I have a Motorola RAZR) there will also be a
MAC address associated with Bluetooth, if you have properly configured the
phone. Where does System Profiler say your MAC address is, en0, en1, or en2?
Where does System Preferences/Network say your MAC address is, Ethernet,
Ethernet 1, Ethernet 2, AirPort, or Bluetooth PAN?

--
email to oshea dot j dot j at gmail dot com.

.



Relevant Pages

  • Re: Question about ethernet addresses
    ... Running System Profiler yields the following for my G5's MAC address ... Opening the Network pane of my System Preferences gives me a completely ... different ethernet address: ... MAC address associated with Bluetooth, if you have properly configured the ...
    (comp.sys.mac.system)
  • Re: MAC address spoofing - conflict?
    ... Ethernet switches split ethernet networks into different collision ... MAC spoofing should not be applicable to thoses environments as it ... Depending on switch behaviour, you may ... WiFi network, as it is a layer 1 share medium too. ...
    (Pen-Test)
  • Re: NAT implementation in an IM driver
    ... Just translate the addresses and ... media types and packet formats). ... but the packet format between WANARP and NDISWAN is fake Ethernet ... (with some fake data in MAC addresses fields), so you can plug an Ethernet IM ...
    (microsoft.public.development.device.drivers)
  • Re: W7 after 3 days of stress testing
    ... Unlike "Snow Job" Leopard there are no broken apps (did not even ... Ethernet, and finding none, I ordered a $5 USB/Ethernet dongle. ... So with W7 you have a lot fo copied features from Mac OS X, ... Works with Windows XP, not with Windows 7. ...
    (comp.sys.mac.advocacy)
  • Re: W7 after 3 days of stress testing
    ... Unlike "Snow Job" Leopard there are no broken apps (did not even ... Ethernet, and finding none, I ordered a $5 USB/Ethernet dongle. ... So with W7 you have a lot fo copied features from Mac OS X, ... Works with Windows XP, not with Windows 7. ...
    (comp.sys.mac.advocacy)