MAC addresses are able to identify us before a network connection , it is what gives us access legality, speaking in that sense. Among the many functions it has, it provides our physical address to those who wish, so it is extremely important when communicating and connecting.
These addresses are not like IPs , since they fulfill different functions, both are very useful when connecting to the Internet. In this post we will show you those details that make each other different.
Here you will find all the necessary information so that you can see your MAC address and change it if you wish, although when we try to make the change we will see that it cannot be done with the entire address, only for some bits .
Index:
What is a MAC address and what is it for in computing and networks?
Within the computer networks there is the MAC address , known by its acronym Media Access Control, with a 48-bit identifier, with 6 blocks of hexadecimal characters (8 bits) corresponding only to the network card or device.
This address is also known as physical address and is different for each device, it serves as an identifier, configured by the IEEE (the last 24 bit) and its manufacturers that corresponds to the first 24 bits, using the Organizationally Unique identifier.
The protocols work in two layers of the OSI model , using three numbers that are handled by the IEEE: MAC-48, EUI-48 and EUI-64, which are completely designed with codes that identify, these are globally unique.
What are the main features of a MAC address?
MAC addresses are characterized by having 6 blocks with 8 binary digits each, which gives us a total of 48 unique bits that identify the device or network card, also known as NIC ( Network Interface Card).
In layer 2 it works with an OSI model, this being the one that allows the communication or linking of the data, they also use one of the three numbers managed by the IEEE (known in Spanish as the Institute of Electrical and Electronic Engineering):
- MAC-48
- EUI-48
- EUI-64
Used together with the IP address to identify the devices communicating what their physical address is. These codes are defined at the time of manufacture, so they can also be called burned-in addresses in English.
This address is used for different technologies , which include:
- Ethernet
- 3 CSMA / CD
- 5 or ring networks at 4 Mbps or 16 Mbps
- 11 wireless networks (Wi-Fi ).
- Asynchronous Transfer Mode
The MAC address uses different frames for information blocks that contain a header corresponding to the sender and receiver of the information.
Bit Classification
The bits comply with a sequence where the MAC address is divided into 4 areas, in which they are encoded as follows:
- Bit 1 (recipients ), is the first bit that indicates whether it is an individual or group address, this bit is also called I / G, which is the abbreviation of individual / Group If it is equal to zero it is a unicast address, that is to say for a single network adapter, on the other hand if it is multicast in equal to one, that is addressed to several recipients .
- Bit 2 (issuing office), this is the second bit, which indicates if the address is valid globally globally), or if it was assigned locally, called by the acronym U / L , where if it is equal to zero it is from a universal administration (UAA), and if it is equal to one it is purely local.
- Bits 3 – 24 (manufacturer identification), these bits are those that identify the organization or manufacturers, assigned by the IEEE, this assignment is generally public and can be determined through a database.
- Bits 25 -48 (identification of the network adapter), these bits, are responsible for providing or identifying the hardware, so its acronym is unique by the OUI.
How does MAC addresses work on the main operating systems?
As we have already mentioned the MAC address is our physical address, so if we want to know what is on our device, we need to read below:
On Android
To obtain the MAC addresses in our Android we must first enter the configuration , and since this is the one that shows the physical location of the device that establishes an Internet connection, click on the of “Networks” or “Wi-Fi” and we choose the “Advanced settings”.
In this way our MAC address will appear at the bottom of the screen .
On iOS
To get our physical address from our MAC iOS , we must go to “Settings”, and go to “General” and inside we look for the option of “information”, there we will find an address field, we look for the one that says “Wi-Fi Address” and we will see our MAC.
On Mac OS
For Mac OS we open System preferences, then click on “Network” and in the left panel select the network we are connected to.
Now we look for the “Advanced” button located at the bottom of the window, and choose the “Hardware” tab and there we will see our MAC address.
In Windows 10
To find our MAC address in Windows 10 , we just have to enter the command prompt to do so, press the Windows + R keys, and we will see a small window whose name is “ Run” and we write in the field for writing “ cmd” and press subsequentlyEnterleigh.
It will open a command prompt window where we will write ipconfig / all , and we will see the physical address (MAC) of our computer.
On Linux
As in all cases the MAC address shows the physical location of the device , so PCs that have Linux are not excluded from this list. In order to see our MAC on our computer, we must use the ifcongi –a, command from the Linux terminal, to list all interfaces.
The –a parameter is the one that allows us to see all the addresses listed, even the network ones. We identify the address through the features mentioned above and voila.
Is it possible to change the MAC address of my device? How to do it?
Our PC and devices already have a physical address that was given to our network cards from the factory, but there is a possibility to change them if we want to, so if we are interested we must follow the steps below :
In Windows
To change our MAC address in our Windows, we must know that only some aspects can be changed. To make the change we must open the device manager, and press the Windows + X keys so that we can open the start menu options.
Then we must press the right button to start the menu, and in it we go to the option of “Device Manager ” and access.
Within this window we will see a list of all the devices that are connected and those that belong to our team. The task is to identify which or what are the network cards , now we go to the top where we will see an icon of two network screens with the name of “Network adapters ”.
In this part, we click to display the information, but only of the physical network card, because it is the only one that interests us, it is usually differentiated by its brand and model. We double click on the network card, and we go to the advanced options tab looking in the side list “Network Address” although in some cases is “Locally Administered Address”.
There we mark the “value” field on the right side, so we can change our MAC address, and write that address that we want to be handled from now on.
To conclude we accept to save the changes, and to verify that the changes have been made we go to the PowerShell and write ipconfig / all and there we confirm the MAC.
On Mac OS
To change our Mac address in our Mac OS we must first open the menu , then go to the search engine and select the option that says “ Utilities ”, and open the application that says “Terminal “.
Next we must write the following command:
- Ifconfig –a
With this command we can see in the list all the interfaces of the system , there we select ours, which usually is the Ethernet interface having assigned a number 0 and the AirPort that It has a number 1.
To change the address of our MAC we must type the following command:
- sudo ifconfig en1 lladdr 00: 0a: 15: e3: b2: c3
We change the interface identifier and address 00: 0a: 15: e3: b2: c3 to 1 by the MAC we want to assign.
On Linux
To change the MAC address of our computer with a Linux system we must first open the terminal, for this we must press Ctrl + Alt + T or also entering the “Applications” window , then in “Accessories” and “Terminal”.
We check the network interfaces we have on our computer with the following command:
- $ ifconfig –a
With this we can observe the network interfaces “Ethernet” starting with the abbreviation Eth, the first are from the wireless networks that start with the abbreviation Wlan, and to verify that we have connectivity with our machine the loopback interface that has an abbreviation lo, whose IP address is 127.0.0.1.
Then we prepare the configuration file with the following command:
- $ sudo nano / etc / network / interfaces
In that file we will have to indicate a new MAC address to those network interfaces that we want. Then to save the changes we must restart the PC
MAC address vs. IP What are the differences between each?
MAC addresses are not equal to IPs, and so you know how to differentiate them we leave you this short list:
- The acronym for MAC means Media Access Control, while the IP is Internet Protocol.
- IP addresses are identified by a device connection via a Network, on the other hand MAC addresses identify a device that participates with a Network hardware.
- These MAC addresses have a 48-bit (6 layers) hexadecimal structure while IP addresses are divided by their two versions, IPv4 with 32 bits, and IPv6 with an address of 128 bits.
- MAC addresses as we have already mentioned are assigned from the beginning by the manufacturer, while IPs are assigned by the providers of Internet services, known as ISP.
- ARP protocols retrieve the MAC address while RARP protocols retrieve IPs, that is, each has a different protocol.