A MAC address is a unique identifier for network adapters or network interface cards.

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102
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How to avoid exposing my MAC address when using IPv6?

On my Macs, each IPv6 address includes the MAC address of a specific computer (not of my router). Sites such as ipv6-test.com not only show it, but even tell me it belongs to an Apple computer. This ...
89
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13answers
14k views

What is the exact use of a MAC address?

I understand that IP addresses are hierarchical, so that routers throughout the internet know which direction to forward a packet. With MAC addresses, there is no hierarchy, and thus packet forwarding ...
70
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5answers
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How do I locate the MAC address of my computer?

I am unable to locate the MAC address in a new computer with Windows 7. I've tried ipconfig /all in the console to which I got no items match your search. I also tried getmac. A screen flashed very ...
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6answers
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Is looking for Wi-Fi access points purely passive?

Say I carry a Wi-Fi enabled phone or laptop through an area where there are WAPs. Assuming that I don't actively try to connect to them or otherwise interact with them, is it possible for the owner ...
25
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2answers
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Are MAC addresses unique when coming out of the factory?

According to Wikipedia: A Media Access Control address (MAC address) is a unique identifier assigned to network interfaces for communications on the physical network segment But how unique are ...
23
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14answers
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IP Address vs MAC addresses

why do we need ip addresses if mac address is enough to identify the machine???
16
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2answers
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What happens when two computers on the same network have the same MAC address?

I was reading an article on WEP cracking, which said that filtering MAC addresses was not enough, since there are tools to change what the computer reports as its MAC address. This made me wonder ...
12
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3answers
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What is a MAC address, and what does it reveal about me?

Does my MAC address list my name, ect? How do I find out exactly what the MAC address tells me? I know it's the "physical address" of my laptop, but what exactly does that mean? This is what my MAC ...
11
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7answers
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Why is MAC-based authentication insecure?

Most wireless routers can use MAC-based authentication as part of their overall security scheme. It seems like a good idea, but I've heard that it is very ineffective, because it's easy to spoof MAC ...
11
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4answers
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Inverse ARP lookup

How can I do an inverse ARP lookup in Windows and/or Linux? Say that I have the MAC address of wireless access point which is up and running in the network, but I forgot it's IP address?
10
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2answers
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Proper way for changing MAC address in a linux VM?

I tried to change the MAC address in a ubuntu VM (virtualbox), but after that it threw lots of errors during boot, and then I had no internet connection. Then I saw that the interface was renamed to ...
9
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1answer
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Is your MAC address revealed when you hit up a website?

When you hit up a site, such as cnn.com, does the TCP/IP packet contain the MAC address of your network card? Could cnn.com theoretically record my MAC address?
8
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8answers
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How do I change the MAC address of my network card?

I have a local network in a Windows system where the Admin gives permission to the PCs by their MAC address. But he is on vacations and I have a new PC. How can I change the MAC address of my new PC ...
8
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3answers
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How is the MAC address on a computer determined?

While imaging some computers today, I started to wonder... what if two LAN MAC addresses on two different computers matched?... That would cause some problems. I later came to understand that the MAC ...
7
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12answers
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Why is IP to MAC address translation needed?

On networks that use the TCP/IP protocol, why is the IP address translated into a MAC address? I mean, when every device knows its IP, why further use the MAC address and not use the IP number as ...
6
votes
9answers
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Can a MAC address be traced?

Can the MAC address of a computer be traced to the serial number of a computer? I have the MAC address that is trying to break into my wireless router. Knowing the serial number of the computer would ...
6
votes
4answers
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How to change the MAC address in Win 8 to spoof a Roku Player through a WiFi splash page?

My Linux laptop died yesterday and now I can't watch TV. Let me explain. I use a Roku Player to stream Netflix shows to my television; and a year or two ago, the Internet Service provided in my ...
6
votes
1answer
493 views

Why would my router have different MAC addresses for IP and IPv6 transactions?

Today I was using tcpdump and I noticed my computer was having IPv6 traffic with a particular MAC address that I could not match with an IP using nmap or arping. After looking at the tcpdump logs a ...
6
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3answers
9k views

Finding router's WAN/External MAC address

I want to find my router's WAN MAC address. On the WEB UI, WAN MAC is hidden. SSH / Telnet is not available (password protected) on router. There is no labels/engravings on physical unit which ...
5
votes
7answers
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How can I get the MAC address from my stolen laptop so the police can trace it?

A week ago my HP Mini 110 was stolen. I reported to the police and they asked me about my Laptop's MAC address, which I don't know or had never heard about before. Is there any way to get the MAC ...
5
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4answers
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Is it possible to change my MAC address?

The wikipedia article on MAC address mentions that it is stored in the ROM of the NIC. How can the MAC address be changed then?
5
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3answers
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How do you determine the MAC address on a CR-48?

You get a CR-48 in the mail. You want to use it but the wireless network only allows access to specified MAC addresses. How do you determine the MAC address?
5
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2answers
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Get Mac-Address in Single-User Mode in Mac OS X 10.8?

I was wondering if there is a way to get all the mac addresses of my network interfaces in single-user mode in OS X 10.8. I've tried ifconfig, but since single-user mode doesn't turn on networking, I ...
4
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2answers
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Network interface missing in ubuntu after changing MAC address

Hi I'm using Ubuntu Server on my VirtualBox. But I changed the MAC address of the NIC from virtual box settings. But now I cannot find the interface when I enter ifconfig. What should I do?
4
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3answers
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how to get MAC address for wireless access point?

How can I get the MAC address for the wireless access point in Ubuntu?
4
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2answers
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Create a virtual network interface using the iproute2 “ip link” command with a spoofed MAC address

How can I create a virtual interface similar to the following ifconfig command? $ sudo ifconfig eth1 hw ether 00:01:02:aa:bb:cc SIOCSIFHWADDR: No such device This does not work. I want to set ...
4
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4answers
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How can I randomize my MAC address on boot on both iOS and Mac OS X?

I would like my MAC addresses on my Mac OS X (iMac) and iOS devices (iPhone, iPad) to be randomized on boot. I have no idea how to generate the random MAC, nor to insert it into the boot process. Any ...
4
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2answers
610 views

How is ARP about two VMs running on VMWare?

I know that systems in network connect together with IP and Mac address ,But insofar as i now all of OSs running on virtual machine use a common network card.I want to know how another systems connect ...
4
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1answer
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Do MAC addresses on virtual machines mean anything?

MAC addresses on virtual installations such as VirtualBox are not connected to hardware. Do they have any absolute meaning, and are they registered somewhere, the way hardware MAC addresses are ...
3
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10answers
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How to generate a valid random MAC Address with bash shell

How can i generate a valid random mac adress with bash. The first half of the adress should always stay same like this 00-60-2F-xx-xx-xx just the x value should be generated random?
3
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4answers
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Why do we need IP addresses to communicate within the local network segment?

Because MAC addresses are only usable across the local network segment, we use IP addresses to communicate with other segments via routers. Meanwhile, for local targets, ARP is used to translate IPs ...
3
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4answers
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Is it possible for software to detect your cable modem's MAC address or any unique factor about it?

Is it possible for software to detect your cable modem's MAC address or any unique factor about it? I'm assuming you can't but I want to double check.
3
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3answers
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Given a PC's MAC address, can I find its IP?

Is there a way to get the IP address when all you have is the MAC of an item?
3
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3answers
162 views

Why are not all MAC addresses randomly assigned?

At 48 bits, this would seem reasonably safe: you would need 751 devices on a network to have a 1/1 billion probability of a collision, and 751 devices with entirely layer 2 connections are rare -- ...
3
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2answers
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Can two devices with the same MAC address be on the same network?

What happens if there is a device already connected to a wifi network, and subsequently another device tries to join the wifi network using the exact same MAC address as the original?
3
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3answers
503 views

How do we get the router's MAC address without ARP?

How can a host that does not support Internet Protocol (it runs on layer 2 only) get the router's MAC address so that it can send Ethernet packets over?
3
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3answers
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eth0 not starting on boot after Virtualbox clone

After cloning my CentOS VM in Virtualbox (I used the Reinitialize the MAC address of all network cards option), the original and the clone VM both now has 127.0.0.1 as their IP. Anyone knows how to ...
3
votes
1answer
323 views

Relation between a packet and a frame over the network

I am learning how networks work and I have a question. What is actually sent over the network? A packet/datagram or a frame? I believe it is a packet. If so, let's say Computer A wants to communicate ...
3
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2answers
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Can I find my stolen laptop if I only have its MAC address?

My laptop was stolen about 2 months ago. I have the MAC address. I have contacted the police, but they said they could not find the laptop if it is behind a ADSL modem or any NAT. Is there any way ...
3
votes
1answer
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Assign IP's to certian mac addresses in dd-wrt

I have a Linksys WRT54G/GL/GS that I am running DD-WRT v24-sp2 (10/10/09) vpn - build 13064 on it and for the life of me I can not find a way to assign ip's based on Mac address. Basically I have a ...
3
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1answer
646 views

Need more than 32 wireless mac filters

Are there any home or small business wireless routers that have more than 32 mac address filters? I'm currently using a Linksys WRT120N with a 32 address capacity and 32 is not enough.
3
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2answers
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Why did MAC-Adress Cloning Fix My Router?

I have a Belkin router, and about a year ago, I suddenly lost my internet connectivity from Comcast. The internet worked fine when I plugged it right into my laptop, so I just ignored it. When I ...
3
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3answers
3k views

How to restore MAC address in Linux?

I have changed my MAC address in my Linux machine using ifconfig. Now the problem is I have not saved my original MAC address. I want to restore it without rebooting. Is there a way to do it?
3
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1answer
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Does a USB modem have its own MAC Address?

My USB modem is now showing its MAC address in ipconfig /all. So does that mean that a USB modem has its own MAC address?
3
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2answers
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How do you change your Airport or Ethernet MAC address in Mac OS X 10.6?

I have a MacBook Pro and would like to set a custom MAC address for either my Airport WiFi card, or Ethernet port. In older versions of Mac OS X, you could do it like this: $ sudo ifconfig en0 ether ...
3
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0answers
345 views

Multiple MAC addresses on a single network interface

Since the other question about this (Multiple network interfaces on a single NIC in Windows) only asks about different routing, I'm going to ask this again: Is there any way to create multiple ...
2
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4answers
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In computer networks, when is a MAC address used and when is an IP Address used?

MAC address and IP address are used to uniquely identify a computer. When is an IP address used and when is a MAC address used?
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5answers
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How to find MAC Address of a PC without powering it on?

How to find MAC Address of a PC without powering it on?
2
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3answers
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Is it possible to recognise hardware (router or network card) just by its MAC address?

Just wondering if that is possible. Are there any naming conventions that would allow one to deduce whether the MAC address belongs to a router (of a specific brand), or a network card, etc..
2
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2answers
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How to find MAC address of a machine in my network

At work, we have a network with internal IP addresses given to machines. How can I find the MAC address of machines in my network whose IP address is known to me? Also how do I find the MAC address ...