  Coded caching is a technique that generalizes conventional caching and
promises significant reductions in traffic over caching networks. However, the
basic coded caching scheme requires that each file hosted in the server be
partitioned into a large number (i.e., the subpacketization level) of
non-overlapping subfiles. From a practical perspective, this is problematic as
it means that prior schemes are only applicable when the size of the files is
extremely large. In this work, we propose coded caching schemes based on
combinatorial structures called resolvable designs. These structures can be
obtained in a natural manner from linear block codes whose generator matrices
possess certain rank properties. We obtain several schemes with
subpacketization levels substantially lower than the basic scheme at the cost
of an increased rate. Depending on the system parameters, our approach allows
us to operate at various points on the subpacketization level vs. rate
tradeoff.
