How to find out and change the MAC address of the computer and other devices

The MAC address of the computer, phone, router is just a string of characters. The usual set of numbers and Latin letters, but the importance he has a colossal. It's like a pass to the global network: if there is - pass, but no, it means that they do not let. What is this secret cipher, why without it cannot be connected to the Internet and how to determine it on different devices.

The MAC address of the computer, phone, router is just a string of characters. The usual set of numbers and Latin letters, but the importance he has a colossal. It's like a pass to the global network: if there is - pass, but no, it means that they do not let. What is this "secret cipher", why without it cannot be connected to the Internet and how to determine it on different devices. The identifier was invented at the Ethernet network development stage so that any device connecting to the network could be identified by a unique identifier. Mak is recorded on the device's network card at the factory, but then, in some cases, it can be changed by itself, for example, the Windows operating system makes it easy to do. Previously, it was impossible to do without a special flash programmer.

What is a MAC address. Why one computer can have several of them

Mac Address (Mac Address) - This is an individual 12-digit code that receives each network interface or device is still in the factory. It serves to identify the device on the network when receiving and sending information. It is over Mac a network card receives an IP (for defining IP according to well-known MAC addresses and, on the contrary, the ARP and RARP protocols meet the Ethernet networks). And if there is no IP, there will be no Internet.

How many Mc addresses can one computer and a laptop be? As much as in the network interfaces in the device. For example, if a wired Ethernet adapter is installed on the PC and separately - Wi-Fi, it has 2 MAC addresses.

Mac assigns a device to a device, but this does not mean that your computer, a phone or router connected to it forever. The user has the ability to change this parameter. For what? Some Internet providers practice the hardware binding of subscriber devices - open access to the network only on a well-known mac address. And this limits the freedom of choice.

To register in the Network Settings of the PC or the router, that poppy, which the provider likes, will first have to determine it. How to do it, find out further.

How to find out the mapping address of devices

Computer and laptop under Windows

To find out the computer's address based on Windows, do the following:

  • Right-click on the network icon in the system tray (right area of ​​the taskbar). Select " Network Management Center "If you have Windows 7, or" Network and Internet Parameters "If Windows 10.

Network and Internet Parameters

  • Go to the Network Connection folder by clicking " Setting adapter parameters ".

Setting adapter parameters

  • Open the Connect Connect Context and select " condition ". In the status window, click " Intelligence ".

Interesting!

  • Line " Physical adress "- and there is a poppy adapter poppy.

Stock Android in the search for wireless networks uses a special, registered OUI, one of the few of the seventh bit installed.

Unfortunately, this option is applicable only to active network connections. Be find out the MAC address of the interface that is currently not used, it does not allow. But this can be done by the second method - through the command line.

So:

  • Run in any way the command console or PowerShell.
  • Drive instructions in it. ipconfig -all and press the confirmation key.

Mac address can usually be seen directly on the router or network card. About how to see the poppy, we considered in detail and the examples in the material - how to find out the MAC address of the computer.

The entire list of computer network interfaces will be displayed in the console window, and its physical address will be displayed near each of them. The main thing is to deal with what is connected.

IMAC and MacBook

Learn Mac Addle Mac (Apple Computer) is also very easy. This usually makes the same ways as in Windows - through network settings and terminal (console).

First method - via network settings:

  • Click on the apple (Apple logo) in the upper left corner of the screen and select " System settings ".

The identifier consists of several letters and numbers, has a weight of 6 bytes - 48 bits and recorded in hexadecimal format. The first three bytes are the manufacturer identifier (indicate it), and the remaining three they are simply assigned. Most often, it is written in the form of six hexadecimal numbers separated by commas, for example, 00: CS: DH: FY: 15: 21, but there are other options: 00-CS-DH-FY-15-21 or 00ss.dh: FY.1521.

  • Click the section " Network ".

Mac addresses are issued to equipment manufacturers with a special body - IEEE Registration Authority. It issues them with entire ranges - at least 16 million values, and the manufacturer itself inflicts them on the device at the stage of production. In some, there are concerns that they may not be enough in the future, as well as IP addresses in IPv4 format. But this will not happen soon.

  • Highlight the current connection and in the right half of the window, click " Additionally ".

Why is it needed - how is used

  • In the next window, click the last tab - " Ethernet "Either" Equipment ".

When you connect to the Internet provider, it fixes your Mac Address from a computer or router. And you will only have access to the World Wide Web. If you change it, the Internet simply will not work until the provider will change it in its settings.

  • The desired parameter is in the string " Ethernet identifier " or " MAC address ".

Second way Learn Mac on Mac - through the terminal. It is also enough for a single command too: iFconfig . The physical address of the adapter is displayed in the string " Ether ".

Interesting! In rare cases, it is usually no regional providers - there is no such binding of network access to Poppy. In any case, it needs to be clarified when connected. The router solves the problem to the root, through it the unlimited number of devices can be connected to the Internet.

Routher.

The simplest way to learn the Mac WAN interface of the router is to flip it upside down. In 90-95% of cases, you will find the necessary information on the label.

This is a security system so that some users are not abused, they did not resend access and could not use data from someone else's account to enter the network. Your passwords and account data are attached to the poppy address of the equipment, and even if someone from your network finds out the login and password from the account, it simply will not be able to use them to enter the Internet, at least you are on the network of one provider.

The physical addresses of other interfaces, as a rule, is easy to find in the settings. So products TP LINK. Displays them on the first page:

Finally

ASUS RT-N also:

ASUS RT-N

On other ASUS firmware and on other models of routers, the poppy information can be in other places, for example, in the sections of the wireless and wired network settings.

Phone and tablet

To view the McMartphone or Tablet PC on Android, most often enough to open the settings and go to the section " About the phone " or " About tablet ". The parameter of interest may be in the overall list, in the subsection " Technical information "Either" general information "- Differences are due to the versions and settings of the firmware.

It was the main information on this topic, in the following material we will look at how to see Mac on a computer and a laptop running Windows.

On Apple mobile gadgets (iOS), information about MAC addresses is in the settings, more specifically - in the section " Maintenance "And" About this device ". In the example in the screenshot below they are signed as " Wi-Fi address "And" Bluetooth ".

Mac address

How to change the MAC address

Windows

On PC and laptops running Windows to change Mac, the means of the system itself are sufficient. But provided that this feature is supported by a network adapter driver.

Procedure:

  • Run the device manager, expand the list of network adapters, right-click on your interest key and select it " Properties ".

wireless network

  • Go to the " Additionally ". Find the option in the list of properties Network Address "And in the field" Value »Enter the new poppy.

Mac via the command line

If the properties list does not have the above parameter, it means that the adapter driver does not support the change.

Experienced users can register the MAC address directly to the system registry - to the section where the settings of the network adapter are stored. The easiest way to do this through the command line, launched with admin authorities.

The instruction looks like this:

Reg ADD "HKLM \ System \ Setup \ Upgrade \ NetworkDriverBackup \ Control \ Class \ {4D36E972-E325-11ce-BFC1-08002BE10318} \ ####" / v NetworkAddress / T reg_sz / d 0000000000 / f

Instead of "####" and "000000000000" you need to substitute your data:

"####" is a registry subfolder of the view 0000, 0001, 0002, etc. In such subfolders, the parameters of network interfaces are stored - each in its own. To find out which of the subfolder to record, you will have to open them in the registry and in the list of values ​​to find a mention of the name of the desired network adapter. The same as in the device manager.

Instead of twelve zeros, write a new MAC address without spaces, hyphens and other characters.

System settings

By the way, you can change Mac on a Windows computer in BIOS, but only with a special service software that is not intended for simple users.

Mac OS X.

Change Mc Addresses on Apple computers is made through the same terminal that helped to find out. Enjoy the command in the terminal: Sudo IFCONFIG EN0 Ether 00: 00: 00: 00: 00: 00 .

Instead of zeros after the word " Ether "Write a new address, dividing pairs of colon symbols.

Network button

Android

To change the MAC address on your Android phone or tablet, you need root rights and special software. For devices based on MediaTek processors, it is convenient to use the free service utility MTK Engineering Mode.

  • To go to the desired settings in MTK Engineering Mode, tap the " MTK Settings ". In the list " Connectivity. "Select Wi-Fi or other Network Interface. Open section NVRAM .
  • Enter in the string Add (H, BYTE) Figure 4, and to the next line - Length (BYTE) - Figure 6. Click " Read. ". Below - in the field Value (h) The current physical address of this adapter will appear. It remains to erase it, enter the new (without spaces, hyphens and colon) and click the button Write. .

additional settings

Second way Mac change is available to the owners of devices on processors of other manufacturers, but, unfortunately, it does not work on all devices. In addition, you will have to install a paid Root Explorer utility.

  • Run Root Explorer and go to the catalog / Data. .
  • Find and open a text file with the name in any editor. .nvmac.info. . If it is not, create. To create and save an object in this directory, you need to activate the rights R / W. (read and write)
  • Sunday in .nvmac.info new MAC address, separating the pair of numbers with colon.
  • Open the permissions of this file through the menu and check the reading right for everyone.

Tab The equipment

Routers

The procedure for changing the Mac-Address on routers is called cloning. She is so named because instead of the factory poppy of the router, the system substitutes the poppy computer, which is connected to it. However, you can register instead of a clone and anyone and other address.

The method of cloning the physical address on the devices of different brands and models is almost the same. Differences only in the firmware interface.

To change the parameter that interests on the TP-LINK router (the Archer C20 firmware interface is given as an example), open the section " Network "And" Cloning MAC address ". Push the new value in the screenshot in the screenshot and click " Save ".

MAC address via ifconfig

How to identify the manufacturer of the device in poppy

The physical address of the network device is by no means an arbitrary set of characters, and something like a passport, which contains information about the carrier. In particular, information on which company released it.

Mac Manufacturer Definition Services provide various Internet services. Below are their incomplete list:

Use such services is easier than simple: insert the well-known address in the field and click " Check ". After 1-2 seconds, approximately such a picture will appear on the screen:

Mac at the bottom of the router

As can be seen in the screenshot, this is a TP-LINK brand device produced in China.

Other services work in a similar way.

Image Credit: Christiaan Colen On Flickr

In fact, what is just not happening in computer networks. It is difficult to figure out, but it is especially difficult when it comes to Addressing and receiving / transmitting data. The question is complicated by the fact that each of the addresses functions at its level of the OSI model (Open Systems InterConnection).

Still in Merion Academy

Pass the course on network technologies

To begin

But, no need to worry. In this article, we are the easiest, but professional language explain what is Media Access Control , or as abbreviated it is called Mac - address .

This type of address lives on the second (channel, or Data Link) level of the OSI model and is the main address at this level. It is convenient for the main address at this level, push the "Tchaikovsky" - we will understand.

If you have not heard about the OSI model earlier, we highly recommend reading the article about OSI first, and then start exploring the MAC address.

Media Access Control (Mac) Address - I choose you!

Mac - the address is a unique combination of numbers and letters of 48 characters long. In fact, that's Hardware equipment number (computer, server, router, switch port, and anything), which, Attention , Assigned to the network card of the device still in the factory, that is, at the time of production.

Yes - yes, Mac - the address of the device is not the IP address of the device that can be easily changed. This address is sewn hardware. Although, of course, it is necessary to be honest - as experts from Mytishchi in the garage conditions "will turn" the VIN car number and Mac - the address can be "killed".

Mac - the address is also called the unique physical address of the device that helps identify the device among millions of other devices. In IEEE 802 standard, channel (second, Data Link) OSI model level is divided into two sublevels:

  • LOGICAL LINK CONTROL (LLC) or logical connection management fairy
  • Media Access Control (Mac) or sublayer access control to the environment

And just as you can guess, the MAC is used on the second sublayer, Media Access Control, which is part of the channel level of the OSI model. Now let's talk about how Mac looks like - address from what it consists. We take the A4 sheet and the marker - start drawing.

Mac form - addresses

"I draw! "Here's the picture. We tried to try:

TP-LINK state

Standard Mac looks like this: 00-50-B6-5B-CA-6A .

See: Mac - Address This is 12 - a digital hexadecimal number, or 6 - byte binary number. Most often Mac is the address represent in the hexadecimal system.

In the pictures, we depicted 6 octets (some groups), of which Mac consists of. Each of the octets consists of 2 characters, it turns out 12 - a digital number. The first 6 digits (for example 00-50-B6. ) Indicate the manufacturer of the network card. It is also called Oui. (Organizeal Unique Identifier) ​​- We displayed this part in the picture above.

Here, for example, famous Mac OUI of popular vendors:

  • CC: 46: D6 - Cisco.
  • 3C: 5A: B4 - Google, Inc.
  • 3C: D9: 2B - Hewlett Liackard
  • 00: 9A: CD - Huawei Technologies CO., LTD

And, in fact, the second 6 digits (6 digits on the right) are unique and identified Nic (Network Interface Controller). Often, Mac addresses are recorded in different ways: through a dash, colon, or points. For instance:

  • 00-50-B6-5B-CA-6A - the most common and familiar for all form of recording;
  • 00: 50: B6: 5B: CA: 6A - the recording form is used by parts of everything in Linux systems;
  • 005.0b6.5bc.a6a. - This MAC address format is used by Cisco.
How to find out Mac - address?

So, to find out the MAC address in UNIX / Linux systems, connect the SSH to your server and give commands:

iFconfig -a. 
Mac address Wi-Fi on the phone
IP Link List. 
MAC address iOS
IP Address Show. 
Windows network adapters

To find out the MAC address in Windows systems, open the Machine / Server command line. You can make it by pressing the key combination Win + R. introduce cmd. and press ENTER. As soon as the console opens, give the following command:

IPConfig / All. 
Network controller properties

And if you owner MacBook. Yes, and in general OS X. Devices (like sit in Starbucks and have a great time at the factory "bottle"), then you need to do the following:

  • Open B. Launchliad. "Terminal".
  • Enter the command iFconfig .
  • In line Ether MAC address will be specified
MAC address in the registry

Why?

We carefully work out each Fidbeck and are responsible for the analysis. Write, please, as we can improve this article.

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How to find out the MAC address of the computer

Published 03/05/2017 · Comments:

0

· Read: 7 min

This article will help disassemble how to find out the MAC address of the computer or any other network device running the various operating systems (Windows, Linux, Android and others).

What is a MAC address and why it is needed

The MAC address is a unique identifier of the network card (interface) or wireless adapter. Mac is also called a computer address (hardware address) of a computer, laptop, router, smartphone, in other words - any device operating, in particular, in Ethernet networks. It is the standard Ethernet that provides the use of a unique value of the MAC address consisting of six bytes of information for each network device.

Interesting fact. The uniqueness of physical addresses is achieved by circulation of network card manufacturers to the controlling body, referred to as IEEE Registration Authority, which, turn, allocates pool addresses (more than 16 million values) for appointing new devices.

As the obtained range is used, the manufacturer can contact IEEE again, so to speak, for "adding".

In broadcast networks (for example, such as Ethernet), the physical address makes it possible to determine each node (computer) of the network and deliver the data exclusively to it. It is MAC addresses that form a certain base of networks at a channel level - the component of the OSI model.

The process of determining the physical address for different types of devices and operating systems is slightly different, but still remains fairly simple.

The easiest way to find out the MAC address of the computer is to find the appropriate information on the box of your laptop / router / smartphone (you need to emphasize!) And so on.

But, if this way is not for you, and the box was successfully discharged, or the option with a hike to the mezzles is not an option at all, please continue reading this article.

Determine the MAC address in Windows

How to find out the MAC address of the computer

In order to find out the MAC address of the computer in Windows, you can use three main ways. None of them requires the installation of additional programs or utilities, allowing only the internal capabilities of the "windows".

Method 1. Learning the MAC address via the command line

Windows Command Line is a mandatory tool for each user from the category of "confident". Using CMD (from the COMMAND PROMPT) in the definition of the physical address of the device is universal and is suitable for any version of the popular Microsoft operating system (whether you are checked Windows 7 or Windows 8, new Windows 10 or old good Windows XP).

In order to open the command line, you must use one of the many options. We will highlight two of them most convenient:

  1. At the same time, press the WIN key (button with "windows" in the lower left corner of the keyboard) and the X key (X), after which the context menu appears in which you click on the "Command String"

Wi-Fi Nvram Android

  1. At the same time, press the WIN key and the R key, after which the "Run" window appears. Enter the Word cmd. In the field and click OK.

Changing the MAC address in the TP-LINK routerAfter accessing the command line, you can again go to two ways, more precisely - use two teams:

  • IPConfig / All. - It will show detailed information about all physical and virtual network devices used in the computer. In my case, the system has identified two MAC addresses at once: the physical address of the standard Ethernet port (for a network cable) and a Wi-Fi adapter, which is used to access the network (I do not like all these cables, you know!). Please note that, in addition to information about the MAC address, there are other network data for Wi-Fi adapter (IP address, gateway address, DNS servers and so on).

What is Mac - address

  • getmac - Reports information about the MAC address for all physical instruments of the computer. In my humble opinion is preferable because it does not complicate the life of the user with unnecessary information.

UNIX / Linux IP Link ListUsing additional attributes for the command getmac (/ V. or / Fo List. ) You will receive information in the deployment.

Windows IPConfig / All

Well, now you know how to find out the computer's MAC address via the command line!

Method 2. We are looking for a MAC address in system information

To access information about the operating system, you must use the "Run" tool already known to you (Win + R keys), then enter in the field MSInfo32. As shown in the figure and click "OK".

How to find out the MAC address of the computer | Pingvitech

In the left side of the window that appears to turn the "Components" item (by pressing the "Plus" or Double-click), select "Network", then "Adapter", and on the right side of the window to find the "MAC address" graph.

Opening a command line through Win + X | Pingvitech

Voila! Just, isn't it?

Method 3. Determine the MAC address in network connections

To access the list of network connections, we use the same combination of Win + R (command NCPA.cpl ):

Login to CMD Through Run | Pingvitech

In the window that opens, we find our active network connection and open its properties (right click on the icon):

Ipponfig command result | Pingvitech

Then we bring the mouse cursor the name of the adapter used and get its MAC address in the form of a pop-up text!

Team getmac | Pingvitech

Perhaps the main minus of this method is the inability to copy the value obtained for further use. Yes, and it is impossible to call this way to find out the MAC address of the computer.

How to find out the MAC address in Linux

In order to find out the MAC address of the network interface in the Linux family system, use the command iFconfig (or Sudo ifconfig ) In your favorite terminal. The desired result will be near the word Hwaddr:

root @ host: ~ # iFconfig ETH1 LINK ENCAP: Ethernet Hwaddr 00: 1e: 8c: 26: A1: C8 

Inet Addr: 192.168.1.3 BCAST: 192.168.1.255 Mask: 255.255.255.0 ... (or In Linux OS, the definition of the physical address can also be solved using the command ):

IP. Sudo IP. [root @ localhost ~] # ip link 

...

Link / Ether. iFconfig 00: 1e: 8c: 26: A1: C8

BRD FF: FF: FF: FF: FF: FF Sudo IP. Physical address in Apple Mac OS 

Happy Apple owners can use the terminal (team

) In order to find out the physical address of the computer:

Android

...

Ether.

GETMAC team with attributes | Pingvitech

...

Or, without deepening in the subtleties of the system, go to "System Settings", then "Network", and then refer to the advanced settings and select the adapter: Ethernet (Wired) or Airport (Wi-Fi). The MAC address of the wired interface will be located in the "Equipment" tab, wireless - in the ARPORT ID column.

How to find out information about the system | Pingvitech

Where to see the MAC address of a smartphone or tablet

Methods for defining a MAC address for devices based on the Android operating system if not the same for all devices, it is certainly very similar. Below is an example of how to find out the MAC address on Android (on the example of the MEIZU M3 Note phone).

To do this, go to the "Settings", then in the WLAN Wireless Network Management menu, go to "Advanced Settings", see the desired Mac at the bottom. Hurrah!

Mobile gadgets apple

To view the MAC address on the iPhone / iPad / iPod Touch, go to "Settings", then "Basic", then "On this Device", in the "Wi-Fi address" field specified the physical address of the wireless module.

  1. How to find out the MAC address of another computer
  2. This section will tell you how to find out the MAC address of the remote computer. Important condition: The device with the desired MAC address must be in the same subnet as your computer (it can be a home network or, for example, a network of enterprise). You must also know his IP address. Below are two ways to find out the MAC address on the network: for OC Windows and Linux. Windows Arp. In order to find out the MAC address of the IP computer, you can use the ARP - the built-in Windows utility, which is a software implementation of the network protocol (Address Protocol). In other words, ARP allows you to find out the physical address of the device at its well-known IP address. In order to determine the MAC address of the remote computer (or any other network device), you must perform the following sequence of actions: .
  3. Open the "Command Line" one of the methods known to you. In the row we write a team Ping [Remote Device Address]

Find out the MAC address in the system information | Pingvitech

. For example, I want to determine the MAC address of the router in its home network, then the team will look at:

Ping 192.168.1.1

After "ping" is over, we use the team ARP -A. . The result of the execution of the command will show the physical address of the remote router. 

Linux Arp

We repeat the sequence similar to the previous subsection, but already in the terminal of your Linux distribution. As a result, you will get something like:

NCPA | Pingvitech

Root @ Host: ~ # Ping -C1 192.168.1.1

...

root @ host: ~ # arp

Address Hwtype Hwaddress Flags Mask IFACE

192.168.1.1 Ether

04: 8d: 38: xx: xx: xx

C ETH1.

How to determine the manufacturer by the MAC address

Network connection properties

The user can identify the manufacturer of its "networks" in three seniors (first left) bytes. To do this, insert the MAC address of your device on a special service (for example, here) and press the Submit key.

Network connection properties | Pingvitech

Instead of pre-school

I hope you have found this article interesting and, most importantly, affordable and useful. We are glad that you now know where and, of course, how to find out the MAC address of your or any other device on the network. Now you have become one more step closer to the full mastering of the computer!

Video. Mac address is a unique identifier that is assigned to any active network equipment at the factory. Mac address has network cards of computers and laptops, at routers, with Wi-Fi modules of smartphones and tablets. In general, this address has any equipment that connects to the network. From this article you can find out what Mac address is, as well as how to find out and change it on your computer.

This identifier consists of six bytes and is used to designate the recipient and sender of data packets. Using the MAC address allows you to accurately determine the equipment that each specific data package must receive and send this package exactly where it is necessary.

MAC address in network connection properties

Please note the MAC address is not the same as the IP address. In order not to confuse these concepts, read what is the IP address in another our article.

MAC address in network connection properties | Pingvitech

Mac address is unique on a global scale. There are no two devices with the same MAC address. Such uniqueness is ensured due to the fact that each manufacturer of network equipment has its own address block issued by him by the IEEE Registration Authorit committee. And in the manufacture of equipment, the manufacturer uses addresses only from its block. Such a separation of addresses between manufacturers allows you to exclude repetitive addresses, and also allows you to determine the manufacturer of equipment only by MAC address.

How to find out the MAC address on android

You can learn the MAC address of your computer's network card in several ways. For example, this can be done using the Windows command line. Also, this information can be obtained in the properties of the network card.

In order to learn the MAC address using the command line, you must first execute the CMD command. To do this, click the Win-R key combination to start the "Run" window. After that, in the window that opens, enter the "CMD" command and press the input key.

Now you have the command line of Windows. Now you need to enter the "GetMac" command.

After entering this command, you will receive the information you need.

  • Despite the fact that the MAC address is issued to the equipment at the stage of production, it can be changed by programmatically. In this case, no additional programs or devices will be required.
  • To change the MAC address of the network card, you need to go to "Network Connections". If you have Windows 7 for this you need to go through such a chain:

Start - Control Panel - Network and Internet Maintenance Center and Shared Access - Changing the Adapter Settings.

In the "Network Connections" window, you need to right-click on the icon of your network connection and select "Properties".

In the window that opens, you can see your Mac address, just Mouse over your network card name at the top of the window. In order to proceed to edit the MAC address, click on the "Configure" button.

  • In a new window, which opens after clicking on the "Configure" button, you need to go to the "Advanced" tab and select the "Network Address" item. After that, it will be possible to change the Mac address, scoring it in the "Value" field.

To save the changes, you must close all windows by pressing the "OK" button.

  • Mac addresses are used on the channel level of the model of interaction of open systems on the simultaneous sublevel of this model, Mac suite. Deciphered as Media Access Control - a sublayer of access control to the environment. It is this sublayer that is used if there are several computers and other devices in the data transfer medium.

If we have several devices in the communication channel, then we need to understand what kind of device it is to transmit data, it is for this purpose that the poppy address is used. 0With the help of them, we understand who are specifically designed by those, or other data. Addresses are regulated by IEEE 802. This group includes a large number of local network standards, the most popular Ethernet and Wi-Fi. They use the poppy addresses, the MAC length of 6 bytes (48 bits). The poppy address is recorded as follows:

  • 1C-75-08-D2-49-45

1C: 75: 08: D2: 49: 45

These are six hexadecimal numbers separated by either colon or dash.

Types of MAC addresses

There are three types of addresses:

Individual (Unicast);

When you transmit data to an individual poppy address, then this data receives only one computer connected to the network. 30-9C-23-15-E8-8C

Group (Multicast, the first bit of the older address of the address is 1);

If you transmit data to a group MAC address, then these data receive computers that are included in the group. These computers must be configured to receive data on this group MAC address. In order to indicate that the poppy address is a group, the first bit of the older byte is used, and this bit must be equal to one. 01-80-C2-00-00-08 First bit means younger, so

one.

Broadcast (Broadcast, all 1);

  • This address consisting of all bit units. In hexadecimal, it is recorded here so FF-FF-FF-FF-FF-FF. When the data goes to such an address, they take all computers on the network.
  • Uniqueness of MAC addresses
  • The poppy addresses should be unique on the network, otherwise we will not understand which device should receive this data. If in one network segment there are several devices with the same poppy address, then some of these devices will not work. What kind of? Not regulated, may not work both. Therefore, it is important that the pop address in one segment of the network is not repeated.

Methods of destination

Centralized, which is used by default. The poppy address is written by the equipment manufacturer in each network adapter. There is clear rules that describe how manufacturers should do it. They are contained in the IEEE 802 Family Standard.

Local - addresses are assigned manually by the network administrator, while the administrator itself is already responsible for the addresses in the network segment not repeated.

How to find out the MAC address on android | Pingvitech

In order to understand which method of assigning the poppy addresses is used serves as a second bit of the older byte of the MAC address. If in this bit 0, the address is assigned centrally. The network administrator that is assigned to the MAK address manually is recommended to write down this bit 1. However, no one can do this and control the administrators. If the admin recorded in the second bit of senior macadres 0, the address will still work.

As ensured, the fact that with centralized assignment of MAC addresses, the poppy addresses around the world are not repeated. For this, a hierarchical scheme has been implemented. The poppy address is divided into two parts:

The first 3 bytes are the unique identifier of the organization (Organizationally Unique Identifier, OUI), IEEE equipment manufacturers are issued. Examples of OUI: 00: 00: 0c - Cisco

00: 02: B3 - Intel

00: 04: AC - IBM

The last 3 bytes are assigned to the manufacturer of equipment at its own discretion. The equipment manufacturer must ensure that these 3 bytes are unique.

How to see the MAC address of the computer

Through the command line in Windows - IPCONFIG / ALL and in Linux - ifconfig or IP with the LINK parameter. You can also look through the graphical interface of the network properties.

Conclusion

MAC addresses are the channel-level addresses, they determine which device the data is intended at the channel level. The poppy addresses must be unique within one network segment, otherwise we will not be able to understand what device you need to send data.

Everyone knows that these are six bytes commonly displayed in hexadecimal format, assigned to a network card at the factory, and at first glance. Some know that the first three bytes of the address is the identifier of the manufacturer, and the remaining three bytes them are prescribed. It is also known that you can put yourself

arbitrary

the address. Many have heard about "random addresses" in Wi-Fi.

We'll figure it out what it is.

MAC address (Media Access Control Address) is a unique identifier assigned to a network adapter, applied in IEEE 802 standards networks, mainly Ethernet, Wi-Fi and Bluetooth. Officially, it is called the "EUI-48 identifier". It is obvious from the name that the address has a length of 48 bits, i.e. 6 bytes. There is no generally accepted standard for writing the address (as opposed to the IPv4 address, where the octets are always separated by points). It is widely written as six hexadecimal numbers separated by a colon: 00: AB: CD: EF: 11: 22, although some equipment manufacturers prefer to write a view 00 -Ab-CD-EF-11-22 and even 00ab.cdef.1122. Historically addresses were firmware in the ROM of the network card chipset without the possibility of modifying them without a flash programmer, but currently the address can be changed programmatically from the operating system. You can set manually by the MAC address of the network card in Linux and MacOS (always), Windows (almost always, if the driver is allowed), Android (only routing); With iOS (without root), such a trick is impossible. Address structure The address consists of a part of the manufacturer identifier, OUI, and the identifier assigned by the manufacturer. The assignment of OUI identifiers (Organizationally Unique Identifier) ​​is engaged in organizing IEEE. In fact, its length can be not only 3 bytes (24 bits), and 28 or 36 bits, from which blocks (Mac Address Block, Ma) addresses of LARGE types (MA-L), Medium (MA-M) and SMALL (MA-S), respectively. The size of the block output, in which case, will be 24, 20, 12 bits or 16 million, 1 million, 4 thousand addresses. At the moment, about 38 thousand blocks are distributed, they can be seen by numerous online instruments, for example, with IEEE or Wireshark. Who belongs to the addresses The address consists of a part of the manufacturer identifier, OUI, and the identifier assigned by the manufacturer. The assignment of OUI identifiers (Organizationally Unique Identifier) ​​is engaged in organizing IEEE. In fact, its length can be not only 3 bytes (24 bits), and 28 or 36 bits, from which blocks (Mac Address Block, Ma) addresses of LARGE types (MA-L), Medium (MA-M) and SMALL (MA-S), respectively. The size of the block output, in which case, will be 24, 20, 12 bits or 16 million, 1 million, 4 thousand addresses. At the moment, about 38 thousand blocks are distributed, they can be seen by numerous online instruments, for example, with IEEE or Wireshark. A simple processing of the publicly available database of the IEEE unloading database gives quite a lot of information. For example, some organizations took themselves a lot of OUI blocks. Here are our heroes:

Google is only 40 of them, and it is not surprising: they themselves produce not so many network devices.

MA blocks are not free, they can be purchased for reasonable money (without a subscription fee) for $ 3000, $ 1800 or $ 755, respectively. Interestingly, for extra money (per year) you can buy "concealment" of public information about the dedicated block. Such now, as seen above, 232.

When the MAC is completed

We all are tired of tired of those who have not stopped 10 years about the fact that "IPv4 addresses is about to end." Yes, new IPv4 blocks get not easy. It is known that the IP addresses are distributed extremely unevenly; There are gigantic and few united blocks belonging to large corporations and the US government agency, however, without much hope for their redistribution in favor of those in need. The distribution of NAT, CG-NAT and IPv6 made the problem of shortage of public addresses not so acute.

In the mass address of 48 bits, from which "useful" can be considered 46 (why? Read on), which gives 2

46.

or 10

14

addresses that in 2

Once larger IPv4 address space.

At the moment, approximately the oscillage of addresses is distributed, or only 0.73% of the total volume. Before the exhaustion of Mac addresses is still very, very far away.

Accident of Bit

It can be assumed that the OUI is randomly distributed, and the vendor then accidentally assigns addresses to individual network devices. Is it so? Let us look at the distribution of the bit in the existing bases of 802.11 devices, collected by working authorization systems in WNAM wireless networks. Addresses belong to real devices connected to Wi-Fi for several years in three countries. In addition, there is a small base of 802.3-devices of a wired LAN.

We divide each MAC-address (six bytes) of each of the samples on the Bits of Pickytovo, and look at the frequency of the bits of "1" in each of the 48 positions. If the bit is exposed in a completely arbitrary way, then the probability of getting "1" should be 50%.

  • Where does such injustice from 7 and 8 bits? There are almost always zeros.
  • Indeed, the standard defines these bits as special (Wikipedia):

The eighth (from the beginning) bit of the first byte of the mass address is called a Unicast / Multicast bit and determines which type of frame (frame) is transmitted to this address, normal (0) or broadcast (1) (multicast or Broadcaster). For the usual, unicast network adapter interaction, this bit is set in "0" in all packages, they are sent.

The seventh (from the beginning) bit of the first byte of the mass address is called U / L (Universal / Local) and determines whether the address is globally unique (0), or locally unique (1). By default, all the "manufacturer's stitched" addresses are globally unique, so the overwhelming number of collected VAC addresses contain seventh bits exhibited in "0". In the table assigned OUI identifiers, only about 130 entries has a U / L bit "1", and apparently these are the blocks of MAC addresses for special needs.

With the sixth first bits of the first byte, the bits of the second and third byte in the OUI identifiers, and even more so bits in 4-6 bytes of the address assigned by the manufacturer are distributed more or less uniformly.

Thus, in the real MAC address of the network adapter, the bits are actually equivalent and do not carry technological sense, with the exception of two official bits of the older byte.

Prevalence

I wonder what manufacturers of wireless equipment are most popular? We combine the search for the OUI database with sampling data number 1.

Practice shows that the justice of the contingent of the wireless network subscribers in this place, the greater the proportion of Apple devices.

Uniqueness

Are MAC addresses unique? In theory, because each of the manufacturers of devices (owners of the MA block) is obliged to provide a unique address for each of the network adapters produced by it. However, some manufacturers of chips, namely:

00: 0a: F5 Airgo Networks, Inc. (now Qualcomm)

00:08:22 InPro COMM (now MediaTek)

The last three bytes of the MAC address in a random number is apparently after each restart of the device. There are 82 thousand such addresses in my sample number 1. You can put someone else's, not a unique address, of course, by defining it "like a neighbor" by defining it by a sniffer, or choosing at random. It is also possible to accidentally put yourself not a unique address by performing, for example, restoring the configuration backup of some router like Mikrotik or OpenWRT. What will happen if there will be two devices with one mass address in the network? It all depends on the logic of the network equipment (wired router, wireless network controller). Most likely, both devices or will not work, or will work with interruptions. From the point of view of IEEE standards, the protection against fake addresses is invited to be solved using, for example, MACSEC or 802.1x.

What if you put yourself in the seventh or eighth bit in "1", i.e. Local or Multicast address? Most likely, your network will not pay attention to this, but formally such an address will not correspond to the standard, and it is better to do that. 

How randomization works

We know that in order to prevent tracking the movement of people by scanning the ether and collecting MAC-operating systems of smartphones for several years to use randomization technology for several years. Theoretically, when scanning the ether in the search for well-known networks, the smartphone sends a packet (package group) type 802.11 Probe Request with a MAC address as a source:

The randomization enabled allows you to specify not "stitched", but some other address of the source of the package, changing with each scan cycle, in time or something else. Does it work? Let's look at the statistics of the collected MAC addresses from the air so-called "Wi-Fi Radar":

The picture is completely different. 

The 8th bit of the first byte of the MAC addresses still corresponds to the Unicast nature of the SRC address in the Probe Request package. 7th bits in 92.2% of cases installed in Local, i.e. With sufficient accuracy, we can assume that it is so many collected addresses relates to randomized, and less than 8% to real. In this case, the battery distribution in the OUI for such real addresses roughly coincides with the data of the previous table. What manufacturer, by OUI, belongs randomized addresses (i.e., with 7m bits in "1")?

At the same time, all randomized addresses related to Google belong to one OUI with prefix

DA: A1: 19

. What is this prefix? Let's look at Android sources.

Private Static Final Macaddress Base_Google_Mac = MacAddress.FromString ("Da: A1: 19: 0: 0: 0"); or Stock Android in the search for wireless networks uses a special, registered OUI, one of the few of the seventh bit installed. Calculate the real masse of random

Let's see if:

Private Static Final Long Valid_Long_MASK = (1L << 48) - 1; Private Static Final Long Locally_assigned_mask = MacAddress.FromString ("2: 0: 0: 0: 0: 0"). Maddr; Private Static Final Long MultiCast_Mask = MacAddress. FROMSTRING ("1: 0: 0: 0: 0"). Maddr; Public Static @nonnull Macaddress CreateRandomunicastAddress (MacAddress Base, Random R) {Long Addr; if (base == null) {addr = r.nextlong () & valid_long_mask; } else {addr = (base.maddr & oui_mask) | (NIC_MASK & R.NEXTLONG ()); } Addr | = Locally_assigned_mask; ADDR & = ~ MULTICAST_MASK; MacAddress Mac = New MacAddress (ADDR); if (mac.equals (default_mac_addomenical) {Return CreateRandomunicastAddress (Base, R); } Return Mac; }

The entire address or his youngest three bytes, it is clean
The entire address or his youngest three bytes, it is clean

Random.nextlong ()

  • . "Patent restoration of real mas" - sell. With a lot of confidence, you can expect Android-phone manufacturers and other not registered OUI. The sources of the iOS we do not have, but most likely there is similar to a similar algorithm.
  • The above does not cancel the work of other mechanisms for denyonimizing Wi-Fi subscribers based on the analysis of other Probe Request Frame fields, or the correlation of the relative frequency of the request sent by the device. However, it is extremely problematic to reliably relieve the subscriber by external means. The collected data is more suitable for analyzing the medium / peak load by location and time, based on large numbers, without binding to specific devices and people. The exact data is only in those who are "inside", from the manufacturers themselves, installed applications.
  • What could be dangerous in that someone else knows the MAC address of your device? For wired and wireless networks, you can organize an attack "Refusal of maintenance". For a wireless device, besides, with some probability, you can fix the moment of appearance in the place where the sensor is installed. The address substitution can be tried to "introduce themselves with" your device, which can work only if additional protection facilities (authorization and / or encryption) are applied. 99.9% of people here are nothing to worry about.
  • Mas-address is more difficult than it seems, but easier than could be.
  • Mac address
  • physical adress
  • Devices - a unique identifier of any network device.
  • Mac has every network card, router, hub, swish, smartphone.

This is how the MAC address looks like

  1. So Mac address (physical device address) looks like)
  2. The subtleties of the Mac addressing are very important.

The manufacturer is encoded in the address. That is, we can say who produced the device.

Mac address each device is assigned to the factory in the production of chip.

If the device consists of several network devices, each device will have its own physical address.

MAC address is an identifier of the physical device. That is, all connections of this Wi-Fi and LAN device will have the same mass address. Koryvo sounds, but but reflects the essence.

Virtual devices also have MAC addresses.

Mac The address is necessarily used when transmitting data over the Internet and the local network between adjacent devices. If the device apparently, then you can find out his physical address.

Mac Address change theoretically possible. We go to the device in programming mode and in system values ​​change the address. Yes, you need a special software and direct connection.

The device address can be found or on the label on it (sometimes manufacturers on the board indicate) or directly connecting to it. Why do you need to know about Mac addresses .

I propose to check the connected devices to your network.
I propose to check the connected devices to your network.

Disable other devices to connect to your network.

How to check devices connected to your network

We go to the router and turn on the monitoring mode.

Next, we look at the MACs of the connected devices. Turn off (enough to interrupt the connection) your devices and observe how the address is disappeared. After turning off, all the list of connections should be empty.

At this stage, there are often devices that consume Internet and which forgot - televisions, household appliances, smartphones, sensors, alarm, and so on.

Forbid extra devices on the network

More precisely, the opposite. We go to the settings of the router. We find where you can create a rule and create a new praailo. It will be like this: Allow the connection to devices only with defined MAC addresses. These addresses we already know from the previous paragraph.

Important moment. Use access points - hide them. Bluetooth can be used, since it does not have a physical address in the transmission of the Internet than the Wi-Fi board.

Be find out the MAC address Apple iPhone

More details

On the protection of a home router from foreign connections

Background

Helped the material - deliver like, leave a comment. This will help other Internet users find a solution to a similar problem.

If the topics are interesting - poditize the channel! I recommend my articles:

Mac address - what it is and how to learn it

September 20, 2020

Posted by: Maksim.

Mac Address is a unique network card identifier of any device that can be connected to the network. This is a very important parameter for networks.

He is even in phones. Owners of computers and laptops are most often faced with this term when connecting to the Internet through the provider.

From the past material you learned how to restart the laptop. Now we will consider in detail what the poppy address is how it is used, and why was it in general.

What is the poppy address

Mac Address (Media Access Control Address, Physical Address, Hardware Address, Mac) is a unique identifier that is assigned to a network card / adapter of any device capable of connecting to the Internet. Most often, we see it from: computer, laptop, phones, tablets and other devices. The official name is an EUI-48 type identifier, and it is often referred to as a physical address. Also, the poppy is used when connected via Bluetooth.

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