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tumb · Sep 16, 2009, 01:27 PM

Hello,
I keep have the same alert when I'm surfing (I'm using Safari on Leopard with AT&T).
Do you have any idea where that coming from ? How can I get rid of it ?

Thank you

ibook_steve · Sep 16, 2009, 01:47 PM

Just what it says. There's another machine on your network with the MAC address listed (you really should redact that so nobody knows) with the .100 address. Either you've manually assigned that IP to that other machine and the DHCP server is still trying to give you the .100 address, or you've reserved .100 for two different machines on your router.

Moving to Networking since it's more appropriate there.

Steve

mduell · Sep 16, 2009, 07:27 PM

Originally Posted by ibook_steve

(you really should redact that so nobody knows)

Oh yes, you're going to get exploited now that your MAC address is out in the wild.

Oh wait, no.

ghporter · Sep 17, 2009, 09:13 AM

While it is a remote possibility, there are applications for using pirated MAC addresses. And being paranoid about this sort of thing, I agree with ibook_steve.

In any case, it's important to know what wireless devices are typically in your network. I get that warning occasionally, especially shortly after getting home with my iPhone-which is the device that takes the IP address in question.

mduell · Sep 17, 2009, 03:41 PM

Pirated MAC addresses?
What on earth are you two going on about?

My MAC address is 00:1e:c2:be:e5:03, please don't hack me!

Originally Posted by tumb

I keep have the same alert when I'm surfing (I'm using Safari on Leopard with AT&T).
Do you have any idea where that coming from ? How can I get rid of it ?

What's your home network setup? Router, wired and/or wireless clients, etc.

ghporter · Sep 17, 2009, 09:53 PM

Someone using your MAC to authenticate on some network for the purpose of generating tons of spam could get your computer blacklisted. As I said, the possibility is remote (at least the one I just mentioned), but it's real. The bad guys are REALLY bad, and they don't mind hurting others. I'll keep my private information private, thanks.

mduell · Sep 18, 2009, 01:03 PM

Oh gee, someone might connect to the same wireless network I do and use my MAC address because I posted it on the internet? Good thing those baddies have never heard of ARP!

Enough of this is ridiculous fearmongering.

ghporter · Sep 18, 2009, 02:44 PM

Originally Posted by mduell

Oh gee, someone might connect to the same wireless network I do and use my MAC address because I posted it on the internet? Good thing those baddies have never heard of ARP!

Enough of this is ridiculous fearmongering.

No, someone might spoof your MAC address for theirs when connecting to a network and when they're traced, it's YOUR address that's identified. This is one of the down-sides to trying to track back all the way to the machine that produces the spam. A MAC address conflict on a wireless network is trivial and pretty easy to resolve; having a high end spam blocking package target your computer erroneously is something that can take a very long time to get fixed.

But this IS way off topic, so I think we should drop this line of discussion in any case.

mduell · Sep 18, 2009, 07:17 PM

The remote mail server doesn't get my MAC address, so it's require cooperation of the WLAN administrator. Then what, I'm banned from a network I've never connected to? Wah whaa.

I'm done with this thread until the OP comes back to clarify his network setup.