<s>
A	O
virtual	B-Device
sensor	I-Device
network	I-Device
(	O
VSN	O
)	O
in	O
computing	O
and	O
telecommunications	O
is	O
an	O
emerging	O
form	O
of	O
collaborative	O
wireless	B-Architecture
sensor	I-Architecture
networks	I-Architecture
.	O
</s>
<s>
In	O
contrast	O
to	O
early	O
wireless	B-Architecture
sensor	I-Architecture
networks	I-Architecture
that	O
were	O
dedicated	O
to	O
a	O
specific	O
application	O
(	O
e.g.	O
,	O
target	O
tracking	O
)	O
,	O
VSNs	O
enable	O
multi-purpose	O
,	O
collaborative	O
,	O
and	O
resource	O
efficient	O
WSNs	B-Architecture
.	O
</s>
<s>
The	O
key	O
idea	O
difference	O
of	O
VSNs	O
is	O
the	O
collaboration	O
and	O
resource	B-General_Concept
sharing	I-General_Concept
.	O
</s>
<s>
These	O
networks	O
may	O
further	O
involve	O
dynamically	O
varying	O
subset	O
of	O
sensor	B-Device
nodes	I-Device
(	O
e.g.	O
,	O
when	O
the	O
phenomenon	O
migrates	O
sensors	O
that	O
detect	O
the	O
phenomenon	O
changes	O
with	O
time	O
)	O
and/or	O
users	O
(	O
users	O
that	O
are	O
accessing	O
the	O
network	O
changes	O
with	O
time	O
)	O
.	O
</s>
<s>
Nodes	O
can	O
be	O
grouped	O
into	O
different	O
VSNs	O
based	O
on	O
the	O
phenomenon	O
they	O
track	O
(	O
e.g.	O
,	O
rock	O
slides	O
vs.	O
animal	B-Application
crossing	I-Application
)	O
or	O
the	O
task	O
they	O
perform	O
.	O
</s>
<s>
E.g.	O
,	O
monitoring	O
rock	O
slides	O
and	O
animal	B-Application
crossing	I-Application
within	O
a	O
mountainous	O
terrain	O
.	O
</s>
<s>
E.g.	O
,	O
smart	O
neighborhood	O
systems	O
with	O
multifunctional	O
sensor	B-Device
nodes	I-Device
.	O
</s>
