## 4 Main Tools of the WSN-DPCM Platform
### Tool for Network Commissioning and Maintenance
#### 4.3.1 Hand-Held Device for Network Deployment and in-Field Monitoring
The basic information that is used to build the network connectivity scheme is on the one hand the bidirectional link metrics between pair-points (particularly considering RSSI and LQI parameters), and, on the other hand, the radio communication configurations such as TX power modes and wireless channel assessment. This connectivity scheme is subsequently analyzed and compared with the actual performance  
Figure 19: Overall HW-SW structure of the Hand-held device for the Commissioning and Maintenance Tool. of the sensor nodes under deployment/maintenance, by means of generating a real connectivity scheme in accordance with the runtime node configuration process. As shown in Figure 20a, both simulation and real connectivity maps can be overlapped so that deployers can study the influence of on-site factors and/or installation modifications on the overall performance of the wireless sensor deployment, in addition to deployment methodology sequence outcome. This representation allows the provision of parameters regarding isolated nodes, redundant communication areas and critical points of the network. Four main elements can be distinguished within the system implementation of the CMT-HH, which also define the system functional flow once the internal data management system is supplied with the aforementioned input models. First, an in-field deployment methodology built upon run-time optimization algorithms, so that the users are provided with the most effective configuration and installation routine for the wireless sensor nodes to be deployed in the target scenario. This optimization engine focuses on identifying on the one hand the best deployment sequence to assure the cohesion of the network with an optimized power and resource consumption during the configuration routine; and, on the other hand, to find key-strategy-points of the WSN with which the network topology scheme is achieved with a minimum control packet dissemination cost. Second, an on-site comparative analysis of the actual wireless communication performance of the sensor network with the theoretical simulation models generated at planning stage. Apart from the network/node link correlation schemes based on connectivity metrics and radio module parameter reconfiguration to improve the overall networking map, an experimental evaluation of multi-hop communication mechanisms can also be realized based on routing protocol information provided by  
Figure 20: General view of Hand-held top-level interface in Commissioning and Maintenance Tool. (**a**) Network connectivity and node correlation scheme layers; (**b**) Runtime node functional components management; (**c**) Data aggregation and on-site monitoring/commanding. the sensor platform during deployment considering the monitoring and computation of metrics such as packet loss rate and retransmission counts, as well as routing metrics for path evaluation. Third, run-time functional sensor node reconfigurations that allow to modify specific properties to improve wireless network performance, especially to reduce power consumption (such as the sensor sampling rate and transmission period, sleep mode configurations, transmission power) and network/application debugging tasks. This capability is supported by the Java-based middleware interface functions to access the implemented embedded components of the sensor nodes from the CMT-HH tool, in accordance with the input network model definition. Considering the node objet, block instantiation and parameter identification, a particular functional component of the target sensor node can be addressed and configured at runtime, as shown in Figure 20b, where different block instances and node component parameters can be accessed, updated and monitored. This abstraction layer has been integrated as a two-side interface between the upper debugging and evaluation layers and the USB-host hardware controller of the mobile device.