  Intermittently-powered wireless sensor networks (WSNs) use energy harvesting
and small energy storage to remove the need for battery replacement and to
extend the operational lifetime. However, an intermittently-powered forwarder
regularly turns on or off, which requires alternative networking solutions.
Opportunistic routing (OR) is a potential cross-layer solution for this novel
application, but due to the interaction with the energy storage, the operation
of these protocols is highly dynamic. To compare protocols and components in
like-for-like scenarios we propose module interfaces for MAC, routing and
discovery protocols, that enable clear separation of concerns and good
interchangeability. We also suggest some candidates for each of the protocols
based on our own implementation and research.
