A Media Access Control address (MAC address) is the hard-encoded address given to a piece of networking hardware. This address is assigned by the manufacturer of the hardware and is intended to be permanent. However, that is not always the case.
There are two "types" of MAC addresses -- "software based" and "hardware based." The "hardware-based" MAC address is the address encoded on the hardware. The "software-based" level of address encoding is the one most MAC address-altering software works with.
There are many reasons why you would need/want to change a machine's MAC address. But because some of the reasons people change (spoof) a MAC address are less than innocent, most people assume there are no good reasons why you would want to change a MAC address. There are good reasons to change a MAC address, and the primary reason for making a change is security.
There are security breaches that rely on knowing the MAC address of a machine. By getting this address, a hacker can always find that machine -- even if the address is changed via DHCP. To that end, why not regularly change the MAC address of your more important machines on your network? An added layer of security, especially on this level, is a good thing.
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If the address is typically hard-coded into the hardware, how would you go about making this change? As said earlier, you would change the software-layer address. There are many tools out there that can help you with this process, but none is as easy as SMAC.
Now many people hesitate to employ such tools. I have found some MAC address spoofers to include little extras such as Trojan programs. So it's nice when you can find a tool, normally associated with nefarious tasks, employed by such companies as HP, Cisco, Siemens, Intel, and Boeing.
SMAC is a MAC address changer that has a simple-to-use graphical interface that enables the less experienced user all the way up to the guru to change a piece of hardware's MAC address. The less experienced user will appreciate the random generator whereas the guru will appreciate the ability to hand enter a new MAC address.
SMAC has a number of features to entice the enterprise and the home user:
- Looks up MAC addresses
- Activates active new addresses automatically
- Lists manufacturer of MAC address
- Shows all or active network adapters
- Generates a random MAC address
- Preloads MAC addresses and chooses them from a list (this is not in the demo version)
- Gives you information on your network addressing
- Takes just three clicks to change a MAC address because of GUI
- Hides hard-coded MAC addresses
- Shows detailed information about your network adapter
- Keeps a listing of ten most recently used MAC addresses
- Generates reports
So even if you don't use the spoofing feature of SMAC, the other features available make it worth giving this application a try. With that in mind, let's take a look and see how SMAC does its thing.
Getting and installing
As with any Microsoft Windows application, the installation process is just a matter of downloading the file and double-clicking the installer to begin the process. This installation is no different. A few standard clicks and you are ready to run SMAC.Once it is installed, you will find the application launcher in a Start Menu subdirectory called KLC. Click on that folder and you will see SMAC 2.0. Click on that launcher and the SMAC main window (Figure A) will open.
The disclaimer at the bottom of the window should be fully regarded.
Using SMACUsing SMAC can be very simple, depending on how you want to use it. The simplest way to use SMAC is to assign a random MAC address to a piece of hardware. Before we actually assign a new address, let's take a look at the other hardware on the machine. In the main window there is a check box that tells SMAC to show only active hardware. This checkbox is checked by default. Uncheck that box and your listing will grow, depending on the hardware on your machine. Take a look at Figure B to see how much the listing grows on my laptop that includes wireless, wired, and dial-up connections.
When you click on a different listing, the information about that hardware will be displayed below.Let's change the MAC address of the Wired Marvell Yukon PCI-E Faster Ethernet Controller. To do this, select that entry from the list and click the Random button. As you can see in Figure C, the new, random MAC address is displayed in the New Spoofed MAC Address section.
The address listed will correspond to a manufacturer list that you can choose from.
If you know you want to spoof your MAC address to that of a specific manufacturer you can select a different manufacturer from the drop-down list. When you make this selection, the address listed will change. You can keep hitting Random until you get an address you like (or you can just take the first random address you get).
Once you have your address, select the Options menu and make sure Automatically Restart Adapter is checked. Once that is checked, hit the Update MAC Address button and the new MAC address will be applied.NOTE: In evaluation mode you can only change an address to 0C-0C-0C-0C-0C-01.
As stated earlier, SMAC has a few other features that make it stand out. Here's a quick description of some of those:
- Log Viewer: To view your MAC address log, go to the View menu and select MAC Address Log, which will open a log window where you can view the MAC addresses that have been applied to various network adapters.
- IPConfig: Clicking the IPConfig button will open a window that holds all the information about your currently configured hardware. Figure D shows how this information is displayed.
You will find more information about your network in this window than you will ever need to know.
- Remove MAC Address: You can also easily remove a spoofed MAC address by selecting the hardware and the clicking the Remove MAC button. This will return your hardware's MAC address to its original state.
By now you should see how helpful this tool is. Not only does it spoof MAC addresses easily, but it can also help you get information about your hardware with the simple click of a button. SMAC is a very handy tool to use, just make sure you are using it for the right reasons.
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Jack Wallen is an award-winning writer for TechRepublic and Linux.com. He’s an avid promoter of open source and the voice of The Android Expert. For more news about Jack Wallen, visit his website getjackd.net.