A recent secure authentication service enforcing revocation in distributed
systems is provided. Authenticity entities impose freshness constraints,
derived from initial policy assumptions and authentic statements made by
trusted intermediaries, in authenticated statements made by
intermediaries. If freshness constraints are not presented,
authentication is questionable. The freshness constraints can be
adjusted. The delay for revocation can be arbitrarily bounded. The
freshness constraints within certificates results in a secure and highly
available revocation service such that less trust is required of the
service.