The last posting talked about discovery and how it can be blocked by a firewall. This can also happen with a wireless printer, but another common problem with wireless printers is MAC address filtering.

It is surprising to see how many people try to MAC address filtering as a security feature when it actually creates problems without improving security of a wireless network. Here are a couple of other articles that mention MAC address filtering that you can find on the web:

HP Article – Getting Started with Wireless Networking

“Mac Address Filtering: It is assumed these measures will increase security, but this isn't true. Enabling Mac address filtering and disabling broadcasting of the network name will make the setup and use of the wireless network more difficult.”

Blog – The Six Dumbest Ways to Secure a Wireless LAN

http://blogs.zdnet.com/Ou/index.php?p=43

One reason that MAC address filtering so problematic is that it is a non-standard feature. By "non-standard”, I mean that it is not part of the 802.11 standards. Because it is non-standard, there is no way to tell a client that they are being blocked because of MAC address filtering. Instead, the router tells the client that it has successfully joined the network but then just completely ignores the client. (How rude!)  A typical user will think that they have successfully configured the printer to be on their wireless network, but nothing will work. By the way, most HP wireless inkjets have the ability to detect when it thinks it is being blocked by MAC address filtering. Although the router does not inform the printer of MAC address filtering, if the printer is told it has successfully joined the wireless network but then doesn’t hear anything more from the router, then a good guess is that MAC address filtering is the reason why. Look in your wireless printer documentation to see if it can print a wireless network test report; this will indicate if the printer thinks it is being blocked by MAC address filtering.

We seen MAC address filtering frequently when looking at customer problems with wireless printers. Often they did not set up the network themselves, so they had no idea that MAC address filtering was enabled, or that such a thing even existed. Or they set up the network a long time ago and just forgot about it. Whatever the reason, it happens frequently and customers are often surprised by it. So be sure to check for this, and think long and hard before setting up MAC address filtering if you set up a wireless network for a friend; are you really doing them a favor or just creating a problem for them?