Finding Your MAC Address On Wireless And Wired Network Cards

The Response To The Press Access Control Question

In the last couple of days I've received a number of e-mails about Ethernet cards, both wireless and wired, and much more particularly, about Media Access Control (MAC) addresses. I believe the primary reason I have received a lot of questions regarding Ethernet cards and MAC addresses is people attempting to secure their house wireless systems as well as their wish to use MAC address blocking. This kind of blocking in wireless systems could be set up to permit or deny specific computer systems to make use of or affix to the wireless network, in line with the MAC address.

My first thought ended up being to write articles nearly MAC addresses and wireless Ethernet. After considering it I made the decision to grow about this and review some specific details about Ethernet cards and communication.

Techniques Used In Finding Your MAC Address And Much More

You will find a number of ways of finding your Ethernet and communications protocol information. Many Ethernet card manufacturer's have proprietary software that may reveal these details however they work in a different way with respect to the manufacturer. Therefore we uses the Home windows 2000 and XP "ipconfig" utility as this is obtainable in nearly all Home windows Os's.

First, visit "start" -> "run" and kind "cmd" with no quotes. Then hit the enter key. In the command line type "ipconfig /all", again with no quotes. Really, just typing ipconfig with no /all works and can only offer you abbreviated specifics of your network cards. A good example of what you are able see by typing the "ipconfig /all" command is below with every item said in eco-friendly lettering:

Fault Tolerant And Highly Availability Personal Computers

You will find a number of ways of finding your Ethernet and communications protocol information. Many Ethernet card manufacturer's have proprietary software that may reveal these details however they work in a different way with respect to the manufacturer. Therefore we uses the Home windows 2000 and XP "ipconfig" utility as this is obtainable in nearly all Home windows Os's.

First, visit "start" -> "run" and kind "cmd" with no quotes. Then hit the enter key. In the command line type "ipconfig /all", again with no quotes. Really, just typing ipconfig with no /all works and can only offer you abbreviated specifics of your network cards. A good example of what you are able see by typing the "ipconfig /all" command is below:

Creation Of The "Ipconfig /All" Command

Home windows IP Configuration

Host Title . . . . . . . . . . . . : Desktop Computer

This is actually the title of the computer, typically defined throughout the home windows installation. However, it may be transformed after installation.

Primary Dns Suffix . . . . . . . : domain.com

In case your computer takes part inside a network like a Microsoft Home windows domain this item could have the title from the domain.

Node Type . . . . . . . . . . . . : Unknown

The Node Type may say Unknown, or peer-to-peer, or in some instances "hybrid". It's a setting which has related to the Home windows Internet Naming Services utilized in certain kinds of Home windows domain systems.

IP Routing Enabled. . . . . . . . : No

This setting determines if Home windows XP or 2000 will work as an IP router. For those who have several network cards you are able to setup the body to do something like a router, sending communications demands in one network to a different. Home windows 2000 could be set up to get this done inside a pretty easy fashion Home windows XP will require a registry modification.

WINS Proxy Enabled. . . . . . . . : No

WINS Proxy is yet another setting that's associated with the "Node Type" we talked about earlier. It's normally not really a needed establishing a house or small office network, or more recent kinds of Microsoft Home windows domain names.

Ethernet adapter Wireless Network Connection 2:

For those who have multiple Ethernet (network) cards inside your systems, when i do within this laptop, you'll have multiple entries. That one is actually the 2nd Ethernet card, an interior wireless Ethernet card.

Description . . . . . . . . . . . : Broadcom 802.11b/g WLAN

This is actually the description from the Ethernet card, normally the Title / Manufacturer and kind of Ethernet card. Within this situation, it's a Broadcom wireless Ethernet card included in my laptop.

Street Address. . . . . . . . . : 00-90-4B-F1-6E-4A

And ideas possess the MAC address. The MAC address is really a 48 bit hexadecimal code and it is suppose to become a totally unique address. It's 48 bits because each number or letter in hexadecimal signifies 8 bits. Hexadecimal amounts vary from ,1,2,3,4,5,6,7,8,9,A,B,C,D,E, F. You will find 6 alpha-number codes hence 6*8=48(bits). The very first 3 codes find out the manufacturer from the card and also the remaining codes are utilized to produce a unique number. Theoretically there will not be a card with same MAC address on the local network. However, you will find a couple of exceptions. You will find software programs where you can change this code. Actually, this can be a step some cyber-terrorist decide to try attack others on the local network. I only say local network because MAC addresses aren't routable between network segments. By spoofing this address, you are able to impersonate another machine around the local network. Traffic which was bound for that intended target could be rerouted towards the hacker's machine. This is actually the address you'd also employ to populate a MAC address, or street address table when establishing your wireless entry way to aid MAC address blocking.

DHCP Enabled. . . . . . . . . . . : Yes

DHCP, or even the Dynamic Host Control Protocol, if enabled means your computer systems Ip has been supplied by a DHCP server you network. The DHCP server might be your wireless entry way, cable/dsl router, cable modem, or perhaps a server in your network. Also, if your DHCP server isn't enabled in your network, your computer systems Operating-system will auto produce a random Ip inside a certain predefined range. Which means you could network several systems together without needing to by hand assign the IP configurations.

Ip. . . . . . . . . . . . : 192.168..117

This parameter gives you your present Ip. The address in the above list is exactly what is known as a "private" address. You will find certain classes of IP addresses which have been put aside for individual use. What this means is for the internal, local, or private network both at home and office. These addresses aren't, or shouldn't, be routable on the web. The Web routes what exactly are known as "valid" IP addresses. Your cable/dsl router or cable modem includes a valid Ip designated to the "exterior" network interface. The exterior interface might be your line or cable television cable.

Subnet Mask . . . . . . . . . . . : 255.255.255.

The Subnet Mask is really a special number, or perhaps in some sense, filter, that stops working your Ip, within this situation private Ip, into certain groups. IP addresses and Subnet Masks could be a complicated matter and would take a whole article to talk about.

Default Gateway . . . . . . . . . : 192.168..254

The default gateway, the IP addresses in the above list, may be the Ip from the device which will route your request, for example whenever you attempt to browse an internet site, to the web. It's a little more difficult than that though as gateways or hubs can route visitors to many different systems, even other private systems. At your house . or small office, this gateway probably is the cable/dsl modem or router.

DHCP Server . . . . . . . . . . . : 192.168..49

The DHCP server, remember we spoken just a little relating to this above, may be the device that assigns your pc an Ip along with other information. DHCP servers can assign a myriad of information for example Default Gateway, Domain Title Servers (DNS), Ip, Subnet Mask, Time Server, plus much more.

DNS Servers . . . . . . . . . . . : 192.168..49, 64.105.197.58

DNS Servers are internal or exterior servers that resolve Properly Accredited Domains (FQDN), for example http://world wide web.defendingthenet.com , to IP addresses. This is accomplished because computer systems don't really transmit your demands while using domain title, they will use the Ip designated towards the FQDN. For many home or small office customers, the main DNS server may be the Ip of the cable/dsl router. Your cable/dsl router than queries an exterior DNS server on the web to do the particular resolution from the FQDN to Ip. The address 192.168..49 is definitely an internal private device on my small network whereas the 64.105.197.58 is definitely an exterior public Internet DNS server and it is present just just in case my router has trouble carrying out the DNS resolution tasks.

Lease Acquired. . . . . . . . . . : Sunday, March 19, 2006 6:38:16 PM

These details informs you whenever your computer received its Ip along with other information from the DHCP server. You will observe it states "Lease Acquired", that's since most DHCP servers only lease the Ip for you from the pool of accessible address. For example, your pool might be 192.168.1.1 through 192.168.1.50. So that your DHCP server has 50 IP addresses to select from when setting your pc its Ip.

Lease Expires . . . . . . . . . . : Wednesday, March 29, 2006 9:38:16 PM

Once the Ip, designated through the DHCP server, lease expires it'll make an effort to lease you an identical or any other Ip. This function could possibly be transformed around the DHCP server. For example, on some completely functional DHCP servers, you are able to configure the Lease never to expire, in order to expire within one day and so forth.

How Come MAC Addresses Essential And Just How Will They Work

To leap to MAC address just for a little. It may seem that IP addresses are the most crucial factor if this involves network communication. The truth is, MAC addresses are extremely important because without one computer systems wouldn't have the ability to communicate over Ethernet systems. Whenever a computer wants to talk with another computer on the local network, it'll make a broadcast request, or request an issue, of who is the owner of a specific Ip. For example, your pc may say "Who's 192.168..254". While using information above, my default gateway is 192.168..254 and can answer "I'm "00-90-4B-F1-6E-4A" 192.168..254". It transmits back its MAC address. That MAC address then adopts what's known as a Address Resolution Protocol (ARP) table on your pc. You can observe these details by visiting the command prompt as if you did above and typing "arp -a". You're going to get information such as the following:

Internet Address Street Address Type

192.168..49 00-12-17-5c-a2-27 dynamic

192.168..109 00-12-17-5c-a2-27 dynamic

192.168..112 00-0c-76-93-94-b2 dynamic

192.168..254 00-0e-2e-2e-15-61 dynamic

The Way A Hacker May Use MAC Addresses Within An Attack

You will observe the IP addresses and right of these the MAC addresses. Without it information, with no MAC address, you wouldn't be reading through this short article at this time. MAC addresses aren't routable like IP addresses. They focus on the local or private network. However, products on the web carry out the same tasks. Hubs and switches maintain a listing of the peer products MAC address much like your computer systems and products in your office or home network. I pointed out above that MAC addresses could be transformed to be able to redirect demands. For example, basically were in your office network and also you had an interior server that required private information as input, I possibly could inform your computer to visit my laptop for the site by broadcasting my MAC address associated with the actual web servers Ip. I'd do that whenever you computer requested "Who's the "Real ServerInchInch. I possibly could setup an imitation server that appears similar to the real factor, and begin collecting information the actual server would normally collect. You can observe how harmful this is often.

Conclusion

You will find other easy methods for you to find your MAC address but they could be a little confusing for those who have several internal network card. Most exterior USB, or PCMCIA wireless and wired Ethernet cards get their MAC address printed in it. In instances where the wired or wireless network card are within your computer, such as with laptops, the MAC address may also be printed at the base from the laptop. Even Desktop systems cards which are placed in PCI slots possess the MAC address printed around the Ethernet card.

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