I must confess I'm puzzled why you consider strong authentication the same as remote attestation for the purposes of this analysis.

It seems to me that your note already identifies one key difference:
remote attestation allows the remote computer to determine if they wish
to speak with my machine based on the software running on my machine,
while strong authentication does not allow this.

That is the difference, but my point is that the result with respect to the control of your computer is the same. The distant end either communicates with you or it doesn't. In authentication, the distant end uses your identity to make that decision. In remote attestation, the distant end uses your computer's configuration (the computer's identity to some degree) to make that same decision.

As a result, remote attestation enables some applications that strong
authentication does not. For instance, remote attestation enables DRM,
software lock-in, and so on; strong authentication does not. If you
believe that DRM, software lock-in, and similar effects are undesirable,
then the differences between remote attestation and strong authentication
are probably going to be important to you.

So it seems to me that the difference between authenticating software
configurations vs. authenticating identity is substantial; it affects the
potential impact of the technology. Do you agree? Did I miss something?
Did I mis-interpret your remarks?

My statement was that the two are similar to the degree to which the distant end has control over your computer. The difference is that in remote attestation we are authenticating a system and we have some assurance that the system won't deviate from its programming/policy (of course all of the code used in these applications will be formally verified :-)). In user authentication, we're authenticating a human and we have significantly less assurance that the authenticated subject in this case (the human) will follow policy. That is why remote attestation and authentication produce different side effects enabling different applications: the underlying nature of the authenticated subject. Not because of a difference in the technology.

P.S. As a second-order effect, there seems to be an additional difference
between remote attestation ("authentication of configurations") and
strong authentication ("authentication of identity"). Remote attestation
provides the ability for "negative attestation" of a configuration:
for instance, imagine a server which verifies not only that I do have
RealAudio software installed, but also that I do not have any Microsoft
Audio software installed. In contrast, strong authentication does
not allow "negative attestation" of identity: nothing prevents me from
sharing my crypto keys with my best friend, for instance.

Well- biometrics raises some interesting Gattica issues. But, I'm not going to go there on the list. It is a discussion that is better done over a few pints.

So to summarize- I was focusing only on the control issue and noting that even though the two technologies enable different applications (due to the assurance that we have in how the authenticated subject will behave), they are very similar in nature.

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