Ethernet configuration of MAC address

[Nadreoh]

Hi everyone,

I'm configuring the Ethernet MAC address over CubeMX for a NUCLEO-F746ZG target. Default address is 00-80-e1-00-00-00 which identifies ST manufacturers.

I was wondering if I can freely manipulate the other 24 bits for an industrial purpose? I guess that as long as my board is connected on a private Network with guarantee that there won't be any MAC address conflict, then it is fine. But there is some risks if not (I tried to configure 2 boards on same network with same MAC, my router seemed confused) ...

Possible solution is then to buy IEEE my own manufacturer ID, or buy a component that already offers an unique MAC identifier.

Can somebody tell me if I'm right or not? Is there any other solution?

Nadreoh

[KnarfB]

There are locally administered MAC addresses (LAA). You cannot use other OUIs https://standards.ieee.org/faqs/regauth.html#10

[Piranha]

> I was wondering if I can freely manipulate the other 24 bits for an industrial purpose?

No, because otherwise I could put the same address on my devices... That's why it is not allowed.

> I guess that as long as my board is connected on a private Network

As KnarfB pointed out, for that purpose there are LAA, which are guaranteed to not collide with any UAA.

https://en.wikipedia.org/wiki/MAC_address#Universal_vs._local

[Nadreoh]

Thanks a lot for your clarifications !

I didn't had this information about LAA vs UAA.