Ubiquitous wireless sensor networks (WSNs) consist
of sensor nodes which may communicate with each other via
unreliable communication links. Furthermore, the sensor nodes
themselves may fail. Ubiquitous WSNs may be used in application
scenarios where they autonomously monitor the environment and
are only sporadically visited by the mobile user for harvesting the
collected sensor data. Thus, high
... [Show full abstract] availability of the measured data
is of paramount priority. But how can the mobile user formulate
this QoS requirement and how can a WSN – honoring such
a QoS requirement – be efficiently implemented? We propose
ZeDDS
1
a middleware and control framework for providing
high available data storage in WSNs. In ZeDDS, we assume
that the WSN is meant for collecting and dependably storing
measured data until the mobile user contacts the WSN for
data harvesting. ZeDDS enables the mobile user to explicitly
specify a particular replication strategy exhibiting a certain data
availability and energy consumption. At run-time, ZeDDS is
appropriately configured and replicates the measured sensor data
according to the replication strategy specified. We evaluate our
ZeDDS implementation in terms of write operation availability
measurements of a WSN consisting of TelosB sensor nodes using
three different well-known replication strategies.
