STM32H7 Unique 96-bit serial number is really Unique ??

[SPati.7]

We are looking for Unique identification number per STM32, in the process we came to know about unique 96-bit serial number. is it really Unique ?? how it Guarantees, that no duplicate exist ??

Can you please help on this clarification ??

INFO

[Tesla DeLorean]

Supposed to be, and supposedly encodes batch, wafer, die site, etc.

Want specific assurances, speak to your FAE, or submit an Online Support Request from the support portal.

[SPati.7]

Thanks @Community member​ for quick response.

[Peter BENSCH]

@Community member​'s statement is absolutely correct: the serial number actually encodes the batch, wafer and location of the chip on the wafer and is therefore completely and absolutely unique, so it can also be used for product identification or encryption.

The signature length of 96bit corresponds to just under 10^29 components, assuming optimistic 10 billion STM32s per year, that would be enough for just under 10^19 years - will be difficult, but we are really trying hard to keep the STM32 alive that long. 😊

Regards

/Peter

[Tesla DeLorean]

The number space is however is sparsely populated..

It's not however a MAC address, and hashing it to smaller widths will cause collisions.

For Root of Trust is should be unique, and if you want your own unique number space, perhaps use OTP