  When data productions and consumptions are heavily unbalanced and when the
origins of data queries are spatially and temporally distributed, the so called
in-network data storage paradigm supersedes the conventional data collection
paradigm in wireless sensor networks (WSNs). In this paper, we first introduce
geometric quorum systems (along with their metrics) to incarnate the idea of
in-network data storage. These quorum systems are "geometric" because curves
(rather than discrete node sets) are used to form quorums. We then propose
GeoQuorum as a new quorum system, for which the quorum forming curves are
parameterized. Though our proposal stems from the existing work on using curves
to guide data replication and retrieval in dense WSNs, we significantly expand
this design methodology, by endowing GeoQuorum with a great flexibility to
fine-tune itself towards different application requirements. In particular, the
tunability allows GeoQuorum to substantially improve the load balancing
performance and to remain competitive in energy efficiency. Both our analysis
and simulations confirm the performance enhancement brought by GeoQuorum.
