ITU‐T's Technical Reports and Specifications 255 Figure 33 – Example of localization Hybrid networks Complete application scenarios generally contain aspects of all three categories. For example, in a sensor network designed to track vehicles, the network may switch between being an alarm monitoring network and a data collection network. During a long period of inactivity when no vehicles are present, the network will simply perform an alarm monitoring function. Each node will monitor its sensors while waiting to detect a vehicle. Once an alarm event is detected, all or part of the network, will switch into a data collection network mode and periodically report sensor readings to a base station, where tracking of the vehicles would be in progress. As a result of this multi‐modal network behavior, it is important to develop a single architecture that can handle all the three aforementioned application scenarios. Figure 34 – Tracking Vehicles