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tramahound · Feb 4, 2005, 03:27 PM

I have a 400mhz powerbook g4 (10.3.7)with the original 802.11b airport card in it. I use a D-Link DL-524 802.11b/g router connected to my dsl modem for web access. I would like to lock out others from using my connection via MAC Filtering. I know where it is in my router set up and turned it on for my desktop and for my powerbook (getting the mac address via the network section of system preferences). Once I turned it on I could not connect to the router at all. Turning the filter off allowed me to get back on the network however.
Do the original airport cards not support MAC address filtering somehow? I could not find anything in the apple knowledge base or via numerous google searches.
Thanks

John Strung · Feb 4, 2005, 04:31 PM

The MAC filtering is done entirely at the router end. If it is not working, it is a problem with your router set up, not with your Airport card.

Don't forget that your Airport card and your ethernet port have different MAC addresses, so you should enter both in your DLink Setup.

tramahound · Feb 4, 2005, 04:34 PM

should I really have to put in the ethernet address if i'm only connecting via wifi?

ghporter · Feb 4, 2005, 05:25 PM

Not ethernet address, the MAC (media access control) address. That's the hardware address of the ethernet card. If you're using MAC filtering, EVERY COMPUTER YOU WANT TO HAVE ACCESS TO THE NETWORK needs to have its MAC address entered in the router.

tramahound · Feb 4, 2005, 05:31 PM

I'm confused. If I'm trying to connect via airport to the router, but have MAC filtering on, I would assume that i need to punch a hole in the filter for my airport card's MAC address. are you saying i need to also add my ethernet MAC address? if so, why and where can i find that? in system profiler under network, the ethernet address?

f1000 · Feb 4, 2005, 06:25 PM

Originally posted by tramahound:
I'm confused. If I'm trying to connect via airport to the router, but have MAC filtering on, I would assume that i need to punch a hole in the filter for my airport card's MAC address. are you saying i need to also add my ethernet MAC address? if so, why and where can i find that? in system profiler under network, the ethernet address?

No, you don't HAVE to add your Ethernet MAC address, but you might as well if you want to occasionally connect via Ethernet.

The MAC address that you should've entered into your router is the AirPort ID (not Ethernet ID). Also, note that 0 means the number zero and not the letter O.

tramahound · Feb 4, 2005, 06:49 PM

well it can't hurt. i'll try to add both the ethernet and airport address and see what's what. i'm positive i did them as zero not O too...

John Strung · Feb 4, 2005, 07:28 PM

Don't mix up the ethernet address, which is a number which looks something like 192.168.1.1, with the MAC address, which looks something like 0A:0B:12:E3:AB:14. It is the MAC address you need. It is sometimes called the Hardware Address or Ethernet ID.

The ethernet address has 4 sets of ASCII numbers between 0 and 255. The MAC address has 6 pairs of hex numbers between 0 and FF.

Tritium · Feb 10, 2005, 01:26 AM

There seems to be some confusion in terms here, 'ethernet address' and 'mac address' are synonyms. MAC addresses are layer 2 addresses, Ethernet is the layer 2 protocol.

A 'dotted quad' is an IP address.

John Strung · Feb 10, 2005, 10:35 AM

You are right, I should have said IP address where I said ethernet address.

ghporter · Feb 10, 2005, 10:41 AM

Originally posted by Tritium:
A 'dotted quad' is an IP address.

DING DING DING!!! Nail on the head time!!!

Tramahound, an address like 192.168.1.1 is an IP address. An address like A0:B1:C2

3:E4:F5 (sometimes it is shown without the colons) is a MAC address; it is the PHYSICAL HARDWARE address of the network card (and we WILL NOT quibble about whether a wireless card hardware address is really a MAC address!!).

Media Access Control address-MAC addresses-tell a low level of the networking protocols what hardware to associate with which IP address. Since they uniquely identify a specific network card, they are useful in specifying what cards are allowed to join the network. You enter the six-part MAC address, not the four-part IP address.

tramahound · Feb 10, 2005, 10:46 AM

ok, so now that that's been established, why would I not be able to get on the network if I had used the MAC address given in System Preferences' Airport section? shouldn't that have been sufficient? any ideas why the powerbook would be kept out?
Thanks for all the replies and info!

John Strung · Feb 10, 2005, 01:30 PM

If you have properly entered the MAC address of the PB's airport interface into the router's MAC address filtering section, you should be able to connect.

tramahound · Feb 20, 2005, 01:36 PM

I tried it yet again and got the same results. i confirmed the airport card's MAC address with that listed in my System Preferences Network/Airport tab and also listed in System Profiler's Network section. They are one and the same. I entered this number along with a generic name in my DL-524's Advanced/Filters/MAC Filters section with the "only allow computers with MAC address listed below to access the network" radio button clicked. Once all this has been done and applied the router restarts and knocks me off my created network. i try to rejoin thinking it's just a result of it restarting and get the "There was an error joining the airport network 'dlink'." I'm sure there is something small i'm missing here...

f1000 · Feb 20, 2005, 02:01 PM

Do you have some sort of encryption or IP filtering activated on the D-link?

tramahound · Feb 20, 2005, 11:02 PM

yes, 64-bit (airport only does up to 64-bit doesn't it?) WEP encryption is turned on. does that tend to cause trouble? can i not have both on?

ghporter · Feb 21, 2005, 11:43 AM

It's always best to get one thing working at a time. Turn off WEP and get the MAC filtering thing going before you mess with WEP.

Here's a point to consider: AirPort equipment interprets password inputs as plain (ASCII) text, while all the other manufacturers' equipment interprets inputs as hexadecimal. In other words, what you typed in as the password on the D-Link is NOT the same thing as what you typed in for your PowerBook.

Read this thread for a link to Apple's explanation.

tramahound · 12:39 PM

is there much need for WEP if I can get MAC filtering working? I mean what kind of security hole would be left open by not using WEP? I would think MAC filtering my network would be just as good if not better than WEP since it is not a guarantee in any way...
or, what about WPA instead of WEP? knowledgebase says WPA doesn't have the same password issues as WEP.

tramahound · Feb 22, 2005, 11:52 AM

I turned off WEP and could not connect my tibook or cube via airport when my MAC filter was on. both got the same error. now i'm thoroughly confused...

SSharon · Feb 23, 2005, 01:43 AM

Originally posted by tramahound:
is there much need for WEP if I can get MAC filtering working? I mean what kind of security hole would be left open by not using WEP? I would think MAC filtering my network would be just as good if not better than WEP since it is not a guarantee in any way...
or, what about WPA instead of WEP? knowledgebase says WPA doesn't have the same password issues as WEP.

MAC filtering will control who has access to your router, but everything will still be sent in the clear (think passwords and credit card numbers). WEP will encrypt everything so other users can't read it (easily) and should therefore be ON.