Trust - Aggregation in a non-homogeneous administrative environment

Security sandboxes must be set up when using data from untrusted sources.

Analogous to a search engine query.
Visiting an untrusted hit is saying "What if I trust this person?"

Communicating trust can be done withing the RDF model.

I trust Fred to write my checks (control over some infrastructure).
      Fred trusts Joe for tax calculations (properties in some set of tax namespaces).

Simple transitive properties are seldom to express trust relations.
Socially, trust is seldom distributive. PGP models limited distributive trust. Tough to model via rules in a language without counting. Need to write a rule for each level of distribution:

I trust the people that Joe trusts for calculations only to calculate interest.