While in a sensor
network, the details of the networks must be of concern, since sensors may be
disabled at any moment, the network layer provides weak services, each node
in a sensor network has very limited storage space, computing ability and
battery power and query processing of the perceptive data is highly related
with the network environment.
The second di?®erence is that, the data produced by a sensor is an infinite
data stream. The data management system of a sensor network manages a
large number of distributed data streams. Infinite data streams cannot be
managed by traditional database systems. The data management system of a
sensor network requires new query processing and analyzing techniques, which
use limited storage space, computing ability and the power to complete the
query and the analysis of a large number of distributed infinite data streams.
The third di?®erence is that, the perceptible data from sensors are not accurate.
The error can be described by some continuous probability distribution
functions, such as Gauss distribution. At present, the errors in sensor networks
are described by discrete probability distribution functions. The data
management system of a sensor network should have the ability to process
the errors of the perceptible data and try to provide credible data.
The forth di?®erence is that, the power of a sensor is very limited. The data
management system of a sensor network needs to reduce the waste of power
to extend the network lifetime.
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