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MAC Address

This menu has settings to let you electronically change (or “spoof”) the MAC Address of various network interfaces. This function does not change the factory-assigned MAC Address in the device's chip. It just overlays a different address in software.


A MAC address is called a Universally Administered Address (UAA) when it's set by the manufacturer or a locally-administered addresses (LAA) when it is assigned by a System Administrator.



The first three octets (group of 8 bits) is the Organizationally Unique Identifier. The OUI is a 24-bit number that identifies the manufacturer, organization, or vendor. The last three pairs of digits are the number specific to the device, or the “Network Interface Controller (NIC)-specific portion” of the address.

For common device names in FreshTomato, see the FAQ page.

How Default WAN MAC Addresses are Derived

Since release 2021.8, FreshTomato configures the WAN port's default MAC Address (based on eth0 / LAN MAC Address) differently.

FreshTomato now sets wanX MAC Addresses as follows:

  • WAN ⇒ eth0 MAC + (decimal) 16 [in 2021.7 and earlier: eth0 = MAC + 1 (decimal value)]
  • WAN2 ⇒ eth0 MAC + (decimal) 17
  • WAN3 ⇒ eth0 MAC + (decimal) 18
  • WAN4 ⇒ eth0 MAC + (decimal) 19


For example, if a router has LAN Ethernet MAC Address: 78:30:AF:DB:0A:F8:

Releases 2021.8 and later would set the WAN MAC Address to 78:30:AF:DB:08:DC, (CC + 16).

Releases 2021.7 and earlier would set the default WAN MAC Address as 78:30:AF:DB:08:CD (CC + 1).

This is illustrated in the following screenshots.



A WAN MAC Address, as Configured in FreshTomato 2021.8 and newer:




A WAN MAC Address, as Configured in FreshTomato 2021.7 and earlier:

mac_address-default-pre-2021.8.jpg


For FreshTomato 2021.7 and earlier: the image above shows the default MAC Address calculated/set. FreshTomato will initially display a different address (after “erase all data in NVRAM memory thorough” has been done). This discrepancy was fixed in release 2022.1.

WAN Port: Here, you can enter a valid MAC Address to be assigned to the WAN interface.

  • Default - Leaves the fixed, factory-assigned Address as the interface's MAC Address.
  • Random - Assigns a random MAC Address to the device.
  • Clone PC - Assigns the same Address as that of the client connected to the web interface.


Some cable and other Internet providers authorize a cablemodem or other device based on its MAC address. Every network has a unique address.
When your modem requests an address from the provider's DHCP server, the provider will either grant it or deny it access to the network based on it's MAC Address.

Some cable companies also authenticate the network card in your client device after you've logged on to their network. This lets them prevent you from using a different LAN client device on their service than the first one you used (whose MAC Address they've recorded). To use another device, you must pay more. In this way, they can force you to use the one client device you've always used.

If the provider's network detects a different MAC Address than the one from the original device, it will deny the client device access to the network. It will only allow devices known to them, in good standing. However, if you let FreshTomato clone your original device's MAC Address, it will fool a cable provider into thinking you're still using the same client device interface to access their services. Your router will be allowed on the network. They don't care which device you use; the MAC is associated with your billing. Often, if you tell them you have a new device, they will change the MAC Address record in their system.


Wireless Interface eth1: Here, enter any valid MAC Address to be assigned to wireless interface eth1.

  • Default - Leaves the fixed, factory-assigned MAC Address as
    the interface's MAC Address.
  • Random - Assigns a random MAC Address to the device interface.
  • Clone PC - Assigns the same MAC Address as the interface of the client
    currently connected to FreshTomato's web interface.


Wireless Interface eth2: Here, enter a valid MAC Address to assign to wireless interface eth2.

  • Default - Leaves the fixed, factory-assigned MAC Address
    as the interface's MAC Address.
  • Random - Assigns a random MAC Address to the device interface.
  • Clone PC - Assigns the same MAC Address as the interface of the client
    currently connected to FreshTomato's web interface.


Wireless Interface wl0.1: A valid MAC Address to assign to wireless interface wl0.1 (typically the first VWLAN).

  • Default - Leaves the fixed, factory-assigned MAC Address as
    the interface's MAC Address.
  • Random - Assigns a random MAC Address to the device.
  • Clone PC - Assigns the same MAC Address as the interface of the client
    currently connected to FreshTomato's web interface.


MAC Address Notes

Until at least release 2021.8, FreshTomato has a problem caused by changing the wireless MAC Address.

Changing the first 3 octets of the MAC Address can cause some issues such as wireless interfaces to drop. For details, please see:
https://bitbucket.org/pedro311/freshtomato-arm/issues/173/wl11-drops-and-upon-restart-attempt-all

advanced-mac.1728254937.txt.gz · Last modified: 2024/10/06 23:48 by hogwild