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

Michael Richardson <> Tue, 29 June 2021 22:40 UTC

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From: Michael Richardson <>
To: Alan DeKok <>, EMU WG <>
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Date: Tue, 29 Jun 2021 18:40:32 -0400
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Subject: Re: [Emu] Question for draft-ietf-emu-tls-eap-types-03
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Alan DeKok <> wrote:
    > On Jun 28, 2021, at 8:50 PM, Michael Richardson <> wrote:
    >> To date, Enterprises with laptops and PCs have provisioned the IDevID into
    >> the TPM, themselves, at the same time the device is wiped and the golden
    >> image is installed.  So, the TPM identity is actually known to them by construction.

    > And... if I have my own phone?  Or if a university wishes to tie
    > devices to student accounts?  So that they can limit (somewhat) abuses?

    > For now, the answer is "too bad".  Or maybe "buy a $$$$ MDM solution".

I think that today, the answer is probably too bad because too complex.
But, I think that most phones can do "Enterprise" WPA, and so a certificate
can be loaded in to do EAP-TLS.

    > As someone who bought my own phone, I'm not going install some MDM
    > solution which lets my employer wipe my personal device.  I would much
    > prefer to be able to prove (a) it's my device, and (b) it has a unique
    > device identifier.  The simpler the method, the better.

If I were a student, I would also not allow a university (or employer) MDM
solution onto my phone, and I'm not actually sure that it directly helps; it
just makes loading that certificate easier.

Michael Richardson <>   . o O ( IPv6 IøT consulting )
           Sandelman Software Works Inc, Ottawa and Worldwide