PCA and RS, practically any price schedule can be realised.

This architecture naturally extends to an arbitrary number of receiving systems to which PCA offers ticket management, and in particular pricing, as services. A further extension would be to let TA express values of tickets by using different (groups of) CSKs. In this way tickets can be associated with additional certified attributes[, [e.g.]{},]{}priorities.

Security and Privacy {#sec:Sec}
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The presented method for the management of tickets provides for perfect pseudonymity of the participants toward the system. In fact, only PCA is able to de-anonymise users.

Note that for the namely reason only PCA can initiate a charging, since only he knows (or is able to know) the identity of a TA and can link it to the identity of the corresponding participant. To keep this pseudonymity strength, it is essential that our concept relies only on genuine TPM functionality, and in particular avoids the usage of trusted software. If there was a trusted software managing tickets in some way at the side of TA, then this software, and the state of the platform would have to be attested both in ticket acquisition and redemption. To this end the TC protocols 