*3.3. Function Layer*

Functions of SWS can be determined by the instrument layer and property layer since different components and properties lead to different functions. For example, one SWS installed with flow and pressure sensor would consider being featured with resourcefulness and can verify the pressure-driven modeling analysis with enormous data collection resources [69]. In contrast, SWS is equipped with temperature sensors functions predicting the infiltration rate in the water systems with available temperature data [70]. Within the architecture of SWS, the function layer is localized in the connection point between system's property and metrics and plays a role in linking these two (shown in the framework Figure 5). Thus, the function layer can be interpreted as the backbone of SWS that includes functionalities of intelligent sensing, simulation, diagnosis, warning, dispatching, disposal, and control [43]. However, this study does not demonstrate the status of a function layer on the whole framework. Based on this function layer, this paper re-designs and specifies the function layer shown in Figure 8, which includes data producing, data sensing, data processing, simulation operating, and application supporting.

**Figure 8.** Function layer designing.

## *3.4. Benefit Layer*

Retrofitting the traditional water supply system with smart devices brings many benefits such as bill reduction for consumers, operation cost decreases for utility, and water loss declines [10]. In this study, the benefit layer mainly contains four aspects including prolonging the asset life cycle, increasing energy sustainability, optimizing pressure and water quality, obtaining real-time water consumption shown in Figure 9 below. According to the benefits taxonomy by [71–73], the first two can be considered as business benefits while the third one belongs to shared benefits. The last benefit is classified as customer benefits.

**Figure 9.** Benefits layer designing.
