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I recently found out that ZigBee devices have MAC addresses.

ZigBee is more related to Bluetooth from what I know rather than Ethernet or Wi-Fi. Do Bluetooth devices such as phones, headphones, wireless speakers, televisions have MAC addresses also? If yes, are those MAC addresses from the same MAC address pool that the Internet Network Interfaces receive? Are the MAC address for these devices assigned by the same organization which assigns MAC addresses for Network cards?

If a phone or other device like a television has more devices that can receive MAC addresses do they have a different MAC for each device? For example a SMART TV that has a RJ-45 port, has a WI-FI antenna for connecting to the internet and has a Bluetooth antenna to connect headphone or do file transfer do each of those interfaces have a different MAC?

How can the MAC address of a Bluetooth device be found?

Can Bluetooth Protocol be considered as running at level 3 of the OSI stack? (instead of the internet protocol)

From what I know the Ethernet protocol runs at level 2 (the data link level). If those other devices have a MAC that means that MAC is not in any way associated with the Ethernet or internet protocols and is completely independent.

Can the internet protocol run over some other layer that DOES NOT require any kind of MAC?

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  • Bluetooth, like ethernet, has 48-bit MAC addresses, but ZigBee uses 64-bit MAC addresses. Each IEEE LAN (layer-2) type uses MAC addresses, but some use 48-bit MAC addresses, and some use 64-bit MAC addresses.
    – Ron Maupin
    Nov 28, 2016 at 1:30
  • @RonMaupin Do you know if a BT Device like a speaker keeps a list of MAC addresses for BT devices it's paired with? I know my Laptop remembers the Speaker's MAC, but is the reverse true?
    – KuboMD
    Mar 18, 2020 at 14:03
  • @KuboMD, I do not know for sure, but questions about hosts are off-topic here. You could try to ask that on Super User or another SE site that deals with hosts/OSes.
    – Ron Maupin
    Mar 18, 2020 at 18:41
  • Did any answer help you? If so, you should accept the answer so that the question doesn't keep popping up forever, looking for an answer. Alternatively, you can post and accept your own answer.
    – Ron Maupin
    Jan 3, 2021 at 5:08

3 Answers 3

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Bluetooth devices are required to have a unique device address, assigned from the same registry as Ethernet and Wifi MAC addresses. Quoting the Bluetooth specification version 5.0 volume 1:

Each Bluetooth device shall be allocated a unique 48-bit Bluetooth device address (BD_ADDR). The address shall be a 48-bit extended unique identifier (EUI-48) created in accordance with section 8.2 ("Universal addresses") of the IEEE 802-2014 standard.

Manufacturers should only use values from a segment of the registry they purchased from the IEEE Registration Authority, and should use a different values for each interface (Bluetooth, Wifi, Ethernet..) a device has. Serious manufacturers attempt to comply, but goofs happen in production.

Caveat: a Bluetooth device is not required to use its BD_ADDR as the Device Address that it broadcasts. It can use a Random Device Address for this purpose. While there are rules governing the generation and classification of a Random Device Address, they most often do not allow to recognize from its value if the Device Address is random, or a BD_ADDR.

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Bluetooth devices are assigned addresses similarly to Ethernet - an organizationally unique identifier (OUI) of 3 bytes followed by another 3 bytes assigned by the vendor. The Bluetooth address of a given device is almost certainly independent of an Ethernet MAC address. Bluetooth OUI lookup tools can be found on Google.

Each device on a Bluetooth network has its own HW address (just like Ethernet). The Bluetooth specification actually lays out both L1 and L2 and, like Ethernet, allows for multiple upper-layer protocols to be mapped (ex: audio streaming, serial, etc) as well as capability negotiation, etc. Bluetooth ends up defining a number of upper-layer protocol functions as well (device naming / discovery, for example).

To your final question - yes, IP can run over media types that don't use MAC addresses. In the context of WAN connections, for example, there is no notion of MAC addressing in point-to-point connections. Similarly in multipoint connections (ATM, FR, etc) there is a direct mapping from IP address to DLCI/PVC. There are similar accommodations in technologies like IPoWDM.

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  • So does this mean that a Bluetooth Device can have the same MAC address as a Ethernet Device?
    – yoyo_fun
    Sep 1, 2017 at 15:51
  • @yoyo_fun: that depends on the meaning you give to MAC address of a Bluetooth Device (is that its BD_ADDR, or the possibly different and randomly assigned Device Address that it broadcasts), and the seriousness of the manufacturers of both the Bluetooth Device and the Ethernet Device.
    – fgrieu
    Dec 7, 2017 at 12:52
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Because BT uses different physical interface or medium than WLAN and Ethernet, a case where BT and WLAN/Ethernet use the same MAC, if any, won't be a problem.

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