MAC Addresses

Sorry everyone, but I've been extremely busy lately!  I've pick up more tasks at work and hardly have time fpr anything!!  So sorry about some incomplete blog posts, but the blog is always a work in progress.  Come back periodically and visit!!

Anyways, needed to find the MAC of a Windows machine (running Windows 7) at work so we could purchase some software and the licenses.  I though to myself, what the heck is a MAC addresses??  It turns out the MAC address is the physical number of your network card or cards (one wireless, one LAN or bluetooth, etc).  Here is some info I found on the web.

From UIC:  http://www.uic.edu/depts/accc/security/os/macaddr.html#2000

In computer networking, a Media Access Control address, better known as MAC address, is a unique identifier assigned to a network adapter or network interface card (NIC) by the manufacturer for identification. The MAC address can also be called the Ethernet Hardware Address (EHA), hardware address, adapter address or physical address. Your computer may have more than one MAC address. Do you have wireless and an ethernet port? Then you have at least two MAC addresses. Your smart phone probably also has a MAC address -- my iPhone has two; one for wireless and one for bluetooth. MAC addresses are typically 6 groups of two hexadecimal digits (0-9,A,B,C,D,E,F), separated either by colons (:) or hyphens (-). The Wi-Fi Mac address on my iPhone, for example is: 00:1C:B3:09:85:15. The first three numbers, 00:1C:B3, are an Apple manufacturing code; only Apple products will have MAC address starting with those digits. (Settings General About Wi-Fi Address. :) Why do you care about MAC addresses? Generally speaking, you don't. But if you are having trouble with connecting to a network or if your computer has been hacked, then the ACCC's security, networking, operations, or repair folks might need you to tell them what it is to help them troubleshoot your problem. So here is how to tell. Note that you must have TCP/IP installed to be able to query your MAC address.

How to find your MAC address?

For Windows:

Windows NT, 2000, XP, Vista, Windows 7 Start Run (in Windows 7, Start and type in the Search Programs and Files box.) Enter: cmd Enter: ipconfig /all If the output scrolls off your screen, and it will on Vista and Windows 7, use: ipconfig /all | more The Physical Address is your MAC address; it will look like 00-15-E9-2B-99-3C. You will have a physical address for each network connection that you have.

Figure 1. The is the ipconfig output on Windows XP. My XP computer has two network connections -- an ethernet connection, labeled Local Area Connection, and a wireless connection, labeled Wireless Network Connection (the wireless connection isn't currently set up). The actual network adaptors present in your computer are all that XP lists. Vista, on the other hand, lists many additional possible network connections, even if they aren't being used. But the Wireless and Local Area Connection sections are the same.  

For Linux:

Linux Become root, using su. 

Enter: ifconfig -a 

# ifconfig -a eth0 

Link encap:Ethernet HWaddr 00:09:3D:12:33:33 

inet addr:10.248.155.17 Bcast:10.248.255.255 Mask:255.255.0.0 

inet6 addr: fe50::234:3dff:fe12:7d73/64 Scope:Link 

UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 

RX packets:3489041718 errors:0 dropped:0 overruns:0 frame:0 

TX packets:3259212142 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000           

RX bytes:2732221481 (2.5 GiB) TX bytes:4065716672 (3.7 GiB) Interrupt:185 

The ethernet devices are called eth0, eth1, and so on The MAC address is in the first line of the output, labeled HWaddr, it is 00:09:3D:12:33:33. (Actually, it's not 00:09:3D:12:33:33, I changed it to protect the innocent.)