## 2 Related Works  
WSN deployments can be classified into two major categories depending on their application: _periodic sampling_ and _object detection/tracking_[3, 10]. These two categories have different requirements and thus they are tested in different scenarios. On one side, periodic sampling applications target extensive operational time periods and require low power consumption due to limited energy resources. The second category aims for shorter operational time periods, low latency, and always-on configurations [3]. The ASWP testbed implements a periodic sampling application. Table 1 summarizes representative multi-hop WSN deployments reported in the past decade, specifying their reported deployment analysis time (_i.e._, the time period covered by its analyzed dataset), network size in terms of the number of deployed nodes, deployment environment (e.g., indoors, outdoors-open area, and outdoors-forested area), hardware platform, and main application category. The first five deployments listed in Table 1 (_i.e._, MoteLab [11], Kansei Genie [5], Indriya [12], SensLab [13] and FlockLab [14]) represent indoor experiments and they are classified in a special category as application testing deployments. The main objective in these works is to allow external users to test their algorithms and protocols by providing a WSN infrastructure. These works are critical during early stages of a WSN application design because they allow programmers to test their code in real WSN motes. Nonetheless, indoor environments (e.g., wall-power supply, common interference patterns, and  
controlled temperature and humidity) are difficult to generalize for external environments where WSN nodes are directly exposed to harsh conditions. He _et al._[15] present VigilNet, a sensor network system designed to support detection and tracking of moving targets. An experiment is carried out using 70 Mica2 motes in an outdoor setting with a maximum expected life of 10, 20, or 48 days, depending on the selected configuration. ExScal [3] represents one of the initial large-scale WSN deployments by using 1200 motes. The deployment was conducted over a 15-day period and it implements an application for intruder detection and tracking. The effect of the environment on the WSN is reported as several motes become non-operational and unexpected faults affect the overall network performance. Trio [2] is an outdoor WSN testbed  
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deployment that incorporates solar panels to the motes. It is evaluated using an object tracking application in 557 solar-powered motes during a four-month operation period. This long network lifetime is due to the inclusion of an energy-harvesting mechanism; however, not all deployments are appropriate for these alternatives (e.g., limited sun exposure) and WSN motes must rely mainly on batteries as their primary energy source. The SNF deployment at the Southern Sierra Critical Zone Observatory in [16] presents 57 WSN motes equipped with solar panels. The WSN periodically samples and collects data from snow depth, soil moisture, humidity, temperature, solar radiation, and matric potential sensors. Its initial deployment of 19 motes was analyzed with results below manufacturer specifications (_i.e._, transmission distances, mote battery lifetime, and transmission reliability). A deployment strategy is proposed and validated with the deployment of the 57 WSN motes. SensorScope [18] is another multi-hop WSN deployment running a periodic sampling application, which also incorporates solar panels to power the WSN motes. Their reported deployment analysis time is two months. Springbrook [4] presents a multi-hop WSN deployment for long-term monitoring of rainforest ecosystems. Authors evaluate the network performance using 10 WSN motes powered using rechargeable batteries and solar panels. Their results show that motes located in forested areas receive as little as 1% of the solar energy received by motes in open areas.