What is MAC address?

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Computer networks formed with various devices need a unique network adapter that comes with a MAC address. A single network adapter from a particular network is given this address to receive a worldwide unique identification number. Even if the network circulates various network adapters like Ethernet or Bluetooth, they will still receive a different unique number. As MAC addresses are assigned right after manufacturing single pieces of hardware, they are also known as physical or hardware addresses. 

An important note here is -device addresses are not the same as MAC addresses because devices come with several network adapters, and they are not given one unique identification number. A MAC address is a 48-bits hardware recognition number assigned to a particular device on one single network in technical terms. In written form, they follow two significant formats, and the first half of it always is used to identify the corporation that is manufacturing the hardware. You can present the addresses in the following manner/syntax: 

AA:AA:AA:SS:SS:SS

AAAA-AASS-SSSS

The first six digits represent the organization, called an Organizational Unique Identifier or an OUI. Some of the well known OUIs are given below as an example: 

CC:46:D6- Cisco 

3C:5A:B4- Google 

3C:D9:2B- Hewlett Packard 

00:A0:C9- Intel Corporation 

The architecture of a MAC Address 

• Any MAC address associated with a network adapter comes with six outlets, and they are divided into three outlets with eight bits each. 
• The first one is called OUI, and it is for recognizing which company manufactured the physical hardware components. 
• Once you are done with the 24-bit number, you will see three pairs of digits that help us understand the device interface or network interface. 
• The next three octets contain eight bits, and they are four main parts encoding with different information. 

• First Part (receiver): The first set of digits helps us figure out whether the address is associated with a group or individual. This set is short of I/G, so it is called a unicast address if it is equal to zero. If the value is equal to 1, then it is multicast, and if it is neither of those two values, then the MAC address belongs to broadcast. 

• Second Part( Registry): The second set of digits is to determine global and local validity. This one is called U/L. If the value is zero, then it is universal, and if it is equal to one, the address is locally administered. 

• Third Part( Identification of Manufacturer): From the 3rd bit to 24th, we consider the organizationally unique identifier introduced by IEEE. 

• Fourth Part( Adapter Identifier): From the 25th bit to 48th, we retrieve a unique number called hardware identifier, and it is assigned to help us find the right network adapter. 

Why care about MAC addresses? 

We always mention the importance of IP addresses, but we tend to forget that IP and MAC addresses complement real-world applications like network routing and device identification. MAC address serves as an essential element in the seven-layer network communication model made by Internal Organization for Standardization(ISO). They take the backup layer two, which was first introduced by the Institute of Electrical and Electronics Engineers (IEEE). The second layer taken by MAC address is again divided into two sublayers called media access control and logical link control. These sublayers take care of the transmission process, and they give all the necessary tools to sustain a physical connection. 

The second most important application of MAC addresses comes with its ability to filter wireless networks. If a user tries to engage with a device with a dynamic IP address, the MAC address can prevent strangers/attackers from gaining access to the network. The routers are designed in a particular fashion where they only have one specific MAC address, so system owners can still identify their device. 

People often misunderstand that MAC addresses have nothing to do with packet transfers because there is no hierarchy. However, there are different protocols for proper authentication of packets processed through Ethernets. 

Data recovery is another important application of any MAC address, and it retrieves the data by using two possible modes called Quick and Deep scan. These methods are deployed using metadata present in the file system. In the deep scan case, the system breaks down multiple levels to reach the binary stage. Most of these methods are present in both Mac and Windows computers. 

How to find a MAC address? 

The older versions used to display MAC addresses using Winnipeg and ipconfig. In Windows, the operating system takes control of the MAC addresses to support the dial-up connections. Some of them even use virtual adapters to lower the use of hardware and increase software implementation. If you want to find your MAC address with little to no effort, you need to access the command line locally and remotely. 

Finding MAC Address Locally

If you want to find a MAC address locally, then follow all of the steps described below: 

Step1: The first step to finding your MAC address is to open your operating system terminal and enter the text- “cmd,” and press enter. After you confirm the pop-up window, we will be redirected to a command-line program. 

Step 2: The process from here on differs based on which operating system is being used for finding MAC address. In Windows 2000, you can enter ipconfig using the “/all” option. Here the terminal output is represented to highlight all the information about IP configuration and local adapters. 

Step 3: Finally, the MAC address is visible under the physical name address, as discussed in the earlier sections. You will also find detailed information about all the network adapters installed. 

Finding MAC address Remotely 

Modern technological advancements in operating systems have made it possible to determine other devices’ MAC addresses. All of these can be deduced while they are in the same local network. The command line used in the remote method is- “arp,” and immediately, you have a terminal output with a detailed report. 

Note- If you need to have a specific identifier, you need to use the command “arp-a” and automatically target that particular network adapter present in the local network. 

The same can be applied to Unix or Linux, depending on the commands used to retrieve MAC addresses. Most of them are attained by reading the boot message sequence to find it from the startup message file. 

Ways to change MAC Addresses in Windows 

• Using Device Manager 

One can use the device manager given in the Windows OS to track down the address and change it accordingly. After you open the device manager window, you should click right next to the arrow to view the list's content.

Once you find the Network Adapters option, you are supposed to long tap for the network card you are willing to chance. Now that you have the desired network card, give a right-click and select properties. In the properties window, select the advanced category and input the new address value. 

• Using Control Panel 

When we are using the control panel to change the MAC address, we must go to the “network connections” and click the first option available on the list.

After clicking “view network connections”, you will see different Bluetooth, Wi-Fi, Ethernet, and VMware network options. In those available connections, you are supposed to right-click on Ethernet and choose properties at the bottom. 

An Ethernet properties window will pop-up, and you need to select the configure button that is highlighted in the picture below: 

Go to the advanced tab and select New Network Address. In the value box, enter the new MAC address and press the OK button. 

• Using Command Prompt 

Command prompt or Powershell is one of the fastest ways to change MAC addresses. It is done by writing a few command lines and storing them in the form of a script. After you store it, you need to run the same procedure to change the addresses repeatedly. The first step in this method involves opening the command line programs as an administrator. It entirely depends on the type of app you prefer to deploy on your system. 

Right before you proceed with the execution process, you need to change two main things associated with your network card and the new MAC address. You can use the Registry editor to find out the information on the first string, and you can change the values of the second string. 

MAC VS IP Addresses 

Here we explore some major differences between MAC and IP address :

Conclusion 

That brings us to the end of the article, and we hope you grasped all the information related to MAC addresses. Some of the key pointers to remember are MAC address identification, real-life use cases, and ways to change MAC addresses on different platforms. Cloning of MAC addresses and using cable modems are some other important aspects of computer networking. These values associated with MAC addresses serve as a key function to many network protocols, and each type of address supports different broadband viewing instances and applications.