On Sat, 3 Aug 2002, James A. Donald wrote:
The TPM has its own secret key, it makes the corresponding public key widely available to everyone, and its own internal good known time. So when your customer's payment goes through, you then
Trusted time is a useful concept. I presume the time is set by the manufacturer. Given current clock accuracy and limited lifetime of backup power I presume it is possible to adjust the time via trusted timeservers. Do they mention anything like this in the specs?
send him a copy of your stuff encrypted to his TPM, a copy which only his TPM can make use of. Your code, which the TPM decrypts and executes, looks at the known good time, and if the user is out of time, refuses to play.
Is there any reason to believe the implementers are telling us everything, and will implement the specs as advertised? I mean, consider the source. Sometimes it makes sense to look a gift horse in the mouth, especially if it's made from wood.