Are MAC addresses unique?
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I was planning to use the MAC address as a serial number. Are they unique? say across 2000 onions.
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@user5456 MAC addresses are by definition unique, they are issued by IEEE so as to ensure they are unique. It is possible to change the MAC of an Omega as it is on most devices.
I would suggest that while you could use the MAC address as a serial number, it is not a good idea. If you require a unique identifier for purposes such as warranty or sales tracking etc you are best to use your own unique serial numbers and cross match them to the MAC address. Don't use sequential serial numbers, it is best to use a secure number generator to generate your serial numbers. Do a google for secure serial number generator, you can find various examples of techniques an free tools. Personally I preferred to develop my own generator so I have greater control over its methodology.
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@user5456 yep, every Omega2 device has 3 unique MAC addresses.
If you don't end up following @crispyoz's suggestion and use MAC addresses after all, here is an application note on the topic: https://onion.io/2bt-apr2-2019/
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@crispyoz said in Are MAC addresses unique?:
I would suggest that while you could use the MAC address as a serial number, it is not a good idea
Why not? whats wrong with it?
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@user5456 As I mentioned MAC addresses can be changed quite easily so assigning a unique serial numbers to each device has a number of benefits:
a) More difficult for a user change MAC address to claim warranty on out of warranty devices;
b) Makes it much easier to identify fakes.
c) The way I generate my serial numbers, I am able to determine some other characteristics of your device if you provide me your serial number.
d) I can change the Omega on the board but the device serial number does not change.Your requirements may be different, I'm from commercial background so these administrative and anti fraud benefits are important to me,
