Bachelor thesis talk Tobias Plötz: Confidentiality of
Values in the Modular Assembly Kit For Security (MAKS)

Abstract:

In real world systems one often has security requirements
that demand the confidentiality of certain values. For
example, in an auction system the value of a bid should
not be disclosed to other bidders. The Modular Assembly
Kit for Security (MAKS) is a framework that permits to
formalize confidentiality requirements. In our work we
investigate how confidentiality requirements like the one
above can be formalized with MAKS for system models
specified as event systems.

We formulate different requirements on the confidentiality
of values as closure properties on the set of possible
system traces, and we discuss how to formalize these
properties with MAKS. To this end, we follow two different
approaches. In the first approach we formalize the
requirements with existing Basic Security Predicates
(BSPs, building blocks for assembling security propertiew
in MAKS), but apply them to transformed event systems. In
the second approach, we introduce new BSPs to capture the
requirements without transforming the event-based system
model. We compare both approaches and show that under a
certain condition they are equivalent. This leads to
insights about different aspects of security requirements
that demand confidentiality of values.