Wireless Sensor and Actuator Networks for Lighting Energy ...

sensor message, which is always the ID of the base station mote since the base server is
the sink that processes and stores sensor information in this implementation. The
function of the sequence number and time to live fields are exactly the same as those in
other message types. The Boolean fused field indicates whether this sensor reading is a
raw sensor data or a fused value generated by an intra-network sensor fusion process.
Recall that it is possible for the photosensors to perform intra-network sensor fusion as
discussed in Chapter 7.4. The reading field carries the sensor reading.
Figure 9-9 Sensor message structure.
The sensor management message type supports managing mote photosensors
over the wireless network from the base server. The management mechanism employs a
broadcast-based protocol like the one used in actuation activities, and all sensors should
respond to the same message. The sequence number and time to live fields have the
same functionalities as those in other message types. The Boolean query field indicates
whether this message is a request for sensor readings. It allows the base server to
request sensor readings using this message with the query field set to true. Sensors
receiving this message immediately acquire a reading and send it back to the base server
in addition to its routine fixed-rate sensing tasks. The Boolean update sensing rate field
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