How are Azure Sphere chips public keys transferred to AS3 by Silicon manufacturer?

Question

In document Anatomy of a secured MCU, from Pluton Key Management section

The chips’ public keys, but not the private keys, are sent to Microsoft from the silicon manufacturer, which means Microsoft knows about and establishes a trust relationship with every Azure Sphere chip from the point the chip is manufactured

As part of Factory floor tasks, only device IDs are recorded, but not public keys of chips. Then, how are the public keys transferred to AS3 by Silicon manfacuturer? Is the process documented?

Answer 1

@Kiran Pradeep

Below is the response from Azure Sphere Product Team, I hope this helps in your query.

As part of device registration process, manufacturer uploads the device public key files to Microsoft through a secured connection. Microsoft associates devices with the public keys.

Do let us know if you have further queries.

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