In this paper we propose a protocol that enables operation
of whitespace networks with the use of geo-location databases,
dynamic control channels deployed depending on the whitespace
spectrum availability, cyclostationary signatures used for
control channel identification, and performance monitoring
to improve the whitespace allocation. The proposed protocol
allows both communication to the broader network (via the
access point) and direct device-to-device links. As part of
our work, we have implemented a proof-of-concept software
defined radio experiment that showcases the capabilities of
the proposed solution. Using the experimental platform we
have evaluated the tradeoffs related to operating exclusively in
whitespaces, without relying on licensed spectrum for control
channels. These tradeoffs come in the form of an extra delay
in the order of hundreds of milliseconds and a throughput of
up to 85% of that achievable with licensed spectrum links.