Wireless sensor networks (WSNs) are an important area with a major technological impact. Power preservation is one of the important issues in communication protocol development for WSNs. This article presents a review of Event-to-Sink Reliable Transport (ESRT) which is specifically developed for an event-based WSNs application. Five characteristic regions and corresponding algorithms have been proposed in ESRT. At the end of each cycle, the reliability is observed and the data reporting rate is adjusted accordingly. Two main contributions of this study include an evaluation of the algorithms proposed by ESRT on their capabilities of power preservation and convergence to the optimal state where a sink receives a desired number of received packets and there is no congestion. According to the results, all of the algorithms demonstrate profound reporting rate adjustments. Moreover, both transmitting and receiving powers can be significantly preserved in the case when the sources generated more packets than required and the network is congested. Therefore, the proposed algorithms unlikely require any enhancements. Moreover, ESRT is analysed how well it can fit in some of the existing WSNs applications. The application category which may deploy ESRT is the event detection and tracking where complete reliability is not required.