What is a MAC Address (Media Access Control)?

What is a MAC Address?

Media Access Control address identifies devices on your local network and all network adaptors have a hard-coded unique identifier called MAC address. All devices connected to the network that is running the internet protocol have an IP address unique to that network. So, in this article, I am going to simplify what is MAC address and its types, how to find the MAC address in windows.

Definition of MAC address:

Media Access Control (MAC) is a sublayer of the data link layer (DLL) in the seven layers of the OSI network reference model. It is responsible for the transmission of data packets to and from the network interface card from another remotely shared channel. Therefore, the basic function of MAC is to provide addressing and channel access mechanisms. So, every node available on the network can communicate with each other with nodes available on the same network or another. Hence, MAC address primary responsibility is physical addressing. But, you can’t find two devices which have the same MAC address as it is a unique code which we cannot change as it is constant.

MAC address is used as a network address for most IEEE 802 network technologies, including Ethernet, Wi-Fi, and Bluetooth.

MAC address

In IEEE 802 standard, Data Link Layer classified into two sublayers –

  1. Logical Link Control(LLC) Sublayer
  2. Media Access Control(MAC) Sublayer
  • It is 48 bits(6 bytes) hexadecimal address
  • Here, the hexadecimal digits can be separated by “-” or “:”
  • Example——–>00-A0-D5-1G-5V-98, 00:A0:D5:1G:5V:98. Hence, the first part of the MAC address contains the ID number of the adapter manufacturer. These ID’s are governed by an Internet standards body. The second part of the MAC address represents the serial number assigned to the adapter by the manufacturer.
  • Media Access Control address can use at the data link layer of OSI and TCP/IP model
  • MAC address can change

How to check your systems MAC address in windows:

  1. open command prompt
  2. Enter command—–>”ipconfig/all”
  3. The physical address F0-DE-F1-77-71-23 this is your systems MAC address

Types of Media Access Control Address:

MAC address classified into three types:

  1. Multicast
  2. Unicast
  3. Broadcast
types o MAC address

Unicast:

Frames intended for Unicast are only sent to the interface that leads to a particular NIC. If the LSB (the least significant bit) of the first octet of the address assigned to zero, the frame can intend to reach only one recipient of the NIC. The MAC address of the source machine is always Unicast.

Multicast:

The multicast address allows the source to send a frame to a group of devices. In the multicast address Layer-2 (Ethernet), the LSB (least significant bit) of the first octet of an address assigned to one.

Broadcast:

Broadcasting is possible in the data link layer. Hence, the frames destined to the MAC address will reach every computer that belongs to that LAN segment.

MAC Filtering:

MAC filtering technique focuses on security method based on access control. Therefore, filtering policies on network equipment can allow or deny access to the network based on a 48-bit Ethernet address that is theoretically unique.

Advantage and Disadvantage of using MAC (Media Access Control) Address filtering:

MAC filtering has no connection fee for devices connected to the network. Policies can set in routers or switches, and connected equipment can be permitted or not. People who place equipment have nothing to do.

MAC (Media Access Control) Address can be spoofed, because of the nature of broadcasting from Ethernet, and specifically wireless ethernet, an advisor can sit on a wire and only listen to the traffic to and fro from MAC address which is permitted. Hence, the advisor can change the MAC address that can permit, and in many cases get access to the network.

Conclusion:

MAC or Media Access Control Address are important elements of computer networks. The MAC address identifies the computer uniquely on the LAN. MAC acts as an important component needed for network protocols such as TCP / IP to function. This is all about the MAC address and its types if you have any queries please mention in the comment section below.

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