Wireless sensor networks (WSN) provide attractive solutions for data exchange in a variety of applications from military surveillance to medical and environmental monitoring. The commonality in all such applications is that the data collected in some nodes of the network is needed at some other nodes, for instance in a data collector node. The nodes are typically limited in terms of power, memory, and processing capability. In this work, we formulate a single-source two-terminal WSN subproblem and design efficient fountain-based transmission protocols aiming to minimize the total number of source transmissions.