Re: [Emu] Question for draft-ietf-emu-tls-eap-types-03

Alan DeKok <> Mon, 28 June 2021 20:00 UTC

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From: Alan DeKok <>
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Date: Mon, 28 Jun 2021 16:00:00 -0400
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Subject: Re: [Emu] Question for draft-ietf-emu-tls-eap-types-03
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On Jun 28, 2021, at 2:20 PM, Tim Cappalli <> wrote:
> The industry is moving away from any hardware identifier being sent off device. I don’t think the physical MAC should ever be used as a device identifier, even for channel binding.

  It's globally unique, which is a pretty useful identifier.

> If a strong hardware-bound identifier is required, the organization should use the TPM/SE for private key generation during provisioning/onboarding.

  From my reading of TCG / TPM / etc. stuff, the private key describes a *particular* device.  Not a *known* device.  i.e. the key is tied to a device, so it's a unique token. But it's not an *identifying* token, in that the administrator can tell which device is being provisioned.

  There still needs to be a way for the administrator to know which device is being used.  Identifying a particular device is done via physical examination in a secure network, or via some unique hardware identifier.  I might be missing something from the whole TPM infrastructure, tho.

  Alan DeKok.