For example,
the user might be interested in all locations where temperature exwhere
communication is performed between two nodes, with unique addresses.
3. WSNs use multi-hop communication to relay data between sensors and
sinks. Each node, besides sensing its surrounding environment, has to be
able to forward data coming from other sensor nodes. In contrast, singlehop
communication is dominant in other wireless networks. For example,
the nodes responsible for data forwarding are the base stations in cellular
communication, and the master nodes in a Bluetooth piconet.
4. InWSNs, nodes are usually densely deployed, in large numbers (thousands
or millions), while in other networks the number of nodes varies from
several nodes to several hundreds. For example, Bluetooth piconets can
support up to eight nodes, while ad hoc wireless networks have usually
less than a hundred nodes.
5. In WSNs, data generated at one node is typically highly correlated with
the data generated by its neighbor nodes and all the nodes in a WSN
tend to serve one application. In traditional wireless networks, however,
data is generated by one node and is independent from the data generated
by neighboring node. Furthermore, nodes may be running di?®erent
applications.
6. In WSNs, sensor nodes might perform data aggregation, by combining
local measurements with data received from neighbors. In this case, only
the combined, assembled results are forwarded toward the sink.
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