RE: Asessment of TAMP with vendor hat on

[Stephen Kent <kent@xxxxxxx>]

Stefan,

A few of observations about you TAM comments, many of which may have 
been stated by others, since I am late in responding:

	- you are right that the presentation we saw in Vancouver 
focused on a solution, not a problem statement. PKIX will need to 
start with a problem statement (or a requirements I-D) that the WG 
agrees upon.  There was considerable discussion of the problem 
statement on the TAM mailing list. I think we can start from the most 
recent iteration there, but this will need to be developed in the 
context of PKIX, i.e., we are not rubber stamping what was done 
before.

	- we need an interoperable solution, in typical IETF style, 
so whatever Microsoft or other vendors have done may be useful as 
input, but it probably is not a substitute for a IETF standard.

	- there were suggestions on the TAM list that offline 
management was needed. So any solution that relies on live 
connectivity is not sufficient, IF the WG agrees with this as a 
requirement.

	- the TAM list also indicated a desire to have a flexible 
management capability, in which one TA, with ultimate responsibility 
for the managed object, can delegate authority to other entities to 
manage TAs with constrained scope. My quick read of what you 
described as the MS management capability did not seem to accommodate 
this sort of delegation. Again, if PKIX decides this is a real 
requirement, that motivates developed of a more sophisticated 
management framework.

	- in certain contexts the receipt capability seems useful, as 
does the ability to query a managed device to determine which TAs are 
installed, etc. Again, we'll have to see whether these are features 
that the WG agrees are needed.  If so, then they motivate a 
request/response protocol model.

	- the secure TA replacement function defined in TAMP seems to 
be attractive, and hopefully not patent encumbered, and would be a 
nice feature for PKIs to have, although I agree that it could be 
accommodated as a cert extension without the rest of TAMP.

Steve