Real Network Cards

You have three options for getting drivers and support for real network cards:

  • Use a driver written for the main chip found on the card (network controller). The problem is that the chip manufacturer usually isn’t the manufacturer of the card, so they won’t provide any support. In fact, they you tell you to contact the card’s manufacturer.
  • You can find out the network card manufacturer through its FCC ID code. This code is written somewhere on the card. With this code you can easily find the manufacturer. The problem is that not all cards have an FCC ID code (especially those not targeted to be sold in the USA) or sometimes they have a different code called FCC REG, which is useless for this task.
  • You can find out the network card manufacturer through its MAC OUI code. We will explain in details how this can be done below.

On Ethernet networks (the kind of network most used) all network cards have a unique address called MAC (Media Access Control), which is stored inside the network card ROM memory. In theory there is no two network cards with the same MAC address (on some network cards you can change its MAC address, especially on on-board models; also some low-end motherboard manufacturers have the bad habit of shipping motherboards using the same MAC address on more than one board, which can cause trouble on your network).

When a machine needs to send data to another machine on the same network, it needs to know the MAC address of the target machine. When a data frame is sent over the network, only the target machine grabs it, as only it will have the target MAC address present on the “target MAC” field of the data frame.

The MAC address is a 48-bit (6-byte) address represented by a series of 12 hexadecimal digits. IEEE controls the attribution of MAC addresses and all manufacturers need an IEEE registration prior to start manufacturing network cards. This registration is called OUI (Organizationally Unique Identifier) and is a 24-bit (3 bytes) code. This OUI code is part of the MAC address. The rest of the MAC address is defined by the network card manufacturer, who should give a unique MAC address for each manufactured card, as already explained. For a better understanding, in Figure 3 you can see the structure of a MAC address.

MAC AddressFigure 3: MAC address structure.

A manufacturer can have more than one OUI code.

If you know the OUI code from the network card MAC address and are able to “decode” it – i.e., check on IEEE’s database what manufacturer has that code – you can easily find out who is the real manufacturer of your network card.

So the first step is to find out the MAC address of your network card. On Windows you can discover this very easily: click on Start, Control Panel and Network Connections. Double click your network connection (e.g., “Local Area Connection”). On the window that will pop up, click on Support tab and then on Details button. Your network card MAC address will be listed there as “Physical Address”, see Figure 4.

MAC AddressFigure 4: Finding out the MAC address of a network card.

As we mentioned before, the MAC address has 12 hexadecimal digits. You will only need to know the first six digits (first three bytes), which is the OUI code. In our example in Figure 4 they were 00-17-31.

The next step is going to IEEE’s website using the link below:

At this website, enter the three bytes under “Search the public OUI listing…” and hit Search! Then the IEEE search engine will tell you which company is proprietary of that OUI number – i.e., your network card manufacturer.

In our example, 00-17-31 belongs to ASUS, as we had an on-board network card on an ASUS motherboard.

Then it is just a matter of going to the manufacturer website to download drivers and/or get support.