MAC addresses by themselves are not useful for authentication, since they are seen in the open on the LAN. If you want to prevent someone from accessing a resource you must use some secret not known by others!.

For communications MAC source addresses can be used as the "claimed source" of a packet, but since anyone can readily put a given MAC address into the SA field this is only a claim that needs to be authenticated (this is what is done by 802.1X and MACsec, which rely additionally on a pre-shared key of public key crypto).

For running programs on a device, MAC addresses are only reliable if they can not be forged, i.e., if there is a direct hardware link over which the MAC address is read that can not be forged by software. This is only the case for proprietary hardware built for this purpose (for example look at the Dallas 1-wire devices), and even then MAC addresses are considered too short for truly sensitive applications.

Y(J)S

Yes, you can use the MAC address of a device as an authentication key for accessing a file. MAC filtering is a security method based on access control. MAC address filtering affixes additional security layer that checks the device’s MAC address against a list of accepted addresses. If the client's address matches that on the list, access will be allowed; otherwise, access will not be permitted.

The following link may help you to understand this topic in detail.

https://www.geeksforgeeks.org/mac-filtering-in-computer-network/

I'm not sure what you are asking. As Amit says, MAC address filtering, say in an enterprise network, is a reasonably good security measure, to keep out intruders. But only of the network is wired. If wireless, it's relatively easy to monitor the communications, and to find MAC addresses that the access points accept!! In wired networks, presumably, switches and routers are physically locked in closets, so intruders would have a more difficult time monitoring packets.

Keep in mind too, that the (source) MAC address of a device will not remain, after the frame has transited across a router. So, this MAC address would have to be carried explicitly as a key, perhaps, if we're talking anything beyond a local area network.

I think these are the main issues. Not a good scheme for any wireless devices, and the business about traversing routers.

MAC addresses by themselves are not useful for authentication, since they are seen in the open on the LAN. If you want to prevent someone from accessing a resource you must use some secret not known by others!.

For communications MAC source addresses can be used as the "claimed source" of a packet, but since anyone can readily put a given MAC address into the SA field this is only a claim that needs to be authenticated (this is what is done by 802.1X and MACsec, which rely additionally on a pre-shared key of public key crypto).

For running programs on a device, MAC addresses are only reliable if they can not be forged, i.e., if there is a direct hardware link over which the MAC address is read that can not be forged by software. This is only the case for proprietary hardware built for this purpose (for example look at the Dallas 1-wire devices), and even then MAC addresses are considered too short for truly sensitive applications.

Y(J)S

Yes it can be done

Depends on what exaclty you want to do. Just a few things to keep in mind:

1. MAC addresses can be seen in LAN and if you are using WLAN you can even see the MAC addresses of the WLAN chips from outside the network.

2. There are plenty of tools out there to easily use a different MAC adress. This way (in combination with 1.) you can simply impersonate another device.

Well, yes you can.

however, with attacks such as ARP poisoning/spoofing, this might not be a reliable solution in some circumstance. You will find several articles online in this regard.

It can be done but it's not secure. MAC addresses are easily spoofed particularly on Wi-Fi.

This wold leave your network wide open and available for hackers and this action is not recommended.

I don't think it's a good idea to use mac address as key for authentication, cause dummy mac could be a latent risk.

All devices that can communicate over the network have their own ID, this 12-digit number is called a MAC address, and it is an abbreviation for media access control. In this article, the most important uses of a MAC address will address the MAC address, how to change it in multiple operating systems, and why?

Your MAC address:

1- The MAC address uses a MAC address at the lowest level of networks. All devices connected to a network use the MAC address to communicate with another device on the same network.

For example, when a web browser on your computer requests a page address from a server, the request passes through several layers of the TCP / IP protocol. The web address that is requested is transferred to the server's IP address. The computer sends your request to the router, which sends the request over the Internet.

On the hardware level, the network card in your computer looks only to the MAC addresses of the devices that you have on the same network, where it identifies the Mac of the router and sends the request directly to it.

2- Obtaining a fixed IP address: The router allows you to adopt a fixed IP every time your device connects to the router by relying on the MAC address of your device's MAC address.

3- Filtering: This process is used to specify _ or prevent _ specific devices only for connection to the network, but this method is not considered safe because of the ability to switch the MAC address.

4- Authentication using MAC address. Address: Some internet providers only allow specific devices to access the Internet, and here you need to change the MAC address of the computer or router.

5- Recognizing devices: Many public WiFi networks such as airport networks depend on the MAC address and MAC address in order to limit the connection to the network for a specific period, as some public networks give you a period of 30 minutes, you can enter the network, in this case the change MAC Address The address of your device will give you 30 new minutes and so on.

6- Tracking devices: Because the MAC address is a specific MAC address, you can track your Mac number when your smartphone searches for nearby networks and publishes its Mac address. In London, Renew London uses this technology to find out the city’s people’s movements.

On Apple iOS 8 devices, the Mac address uses a random MAC address every time you search to prevent tracking in this way.

Each interface network adapter has a special MAC address, so mobile devices that are Wi-Fi and have a wired port. Both the Ethernet adapter and the wireless network adapter each have a MAC address.

MAC address of course provides authentication security but not secrecy or privacy of the user accessing the service as the MAC address is accessible even outside the LAN.

Yes, but it's not secure to use MAC address of device as an authentication key for accessing a file

See https://www.zdnet.com/article/smart-locks-opened-with-nothing-more-than-a-mac-address/ on how dangerous this can be!

Y(J)S

interesting to know