With the cloud emerging as a successful paradigm for
conveniently storing, accessing, processing, and
sharing information, the cloud
market has seen an incredible growth. An ever-
increasing number of providers offer today several
cloud plans, with different guarantees in
terms of service properties such as performance, cost,
or security. While such a variety naturally corresponds
to a diversified user
demand, it is far from trivial for users to identify the
cloud providers and plans that better suit their specific
needs.
In this paper, we address the problem of supporting
users in cloud plan selection. We characterize different
kinds of requirements that
may need to be supported in cloud plan selection and
introduce a very simple and intuitive, yet expressive,
language that captures
different requirements as well as preferences users may
wish to express. The corresponding formal modeling
permits to reason on
requirements satisfaction to identify plans that meet the
constraints imposed by requirements, and to produce a
preference-based ranking
among such plans.