<s>
Topology	B-Device
control	I-Device
is	O
a	O
technique	O
used	O
in	O
distributed	O
computing	O
to	O
alter	O
the	O
underlying	O
network	O
(	O
modeled	O
as	O
a	O
graph	O
)	O
to	O
reduce	O
the	O
cost	O
of	O
distributed	O
algorithms	O
if	O
run	O
over	O
the	O
resulting	O
graphs	O
.	O
</s>
<s>
The	O
term	O
"	O
topology	B-Device
control	I-Device
"	O
is	O
used	O
mostly	O
by	O
the	O
wireless	O
ad	O
hoc	O
and	O
sensor	O
networks	O
research	O
community	O
.	O
</s>
<s>
The	O
main	O
aim	O
of	O
topology	B-Device
control	I-Device
in	O
this	O
domain	O
is	O
to	O
save	O
energy	O
,	O
reduce	O
interference	O
between	O
nodes	O
and	O
extend	O
lifetime	O
of	O
the	O
network	O
.	O
</s>
<s>
Lately	O
,	O
topology	B-Device
control	I-Device
algorithms	O
have	O
been	O
divided	O
into	O
two	O
subproblems	O
:	O
topology	O
construction	O
,	O
in	O
charge	O
of	O
the	O
initial	O
reduction	O
,	O
and	O
topology	O
maintenance	O
,	O
in	O
charge	O
of	O
the	O
maintenance	O
of	O
the	O
reduced	O
topology	O
so	O
that	O
characteristics	O
like	O
connectivity	O
and	O
coverage	O
are	O
preserved	O
.	O
</s>
<s>
This	O
is	O
the	O
first	O
stage	O
of	O
a	O
topology	B-Device
control	I-Device
protocol	O
.	O
</s>
<s>
Topology	B-Device
control	I-Device
has	O
to	O
be	O
executed	O
periodically	O
in	O
order	O
to	O
preserve	O
the	O
desired	O
properties	O
such	O
as	O
connectivity	O
,	O
coverage	O
,	O
density	O
.	O
</s>
<s>
This	O
protocol	O
,	O
based	O
on	O
the	O
Dynamic	B-Device
Source	I-Device
Routing	I-Device
(	O
DSR	O
)	O
routing	O
algorithm	O
,	O
recreates	O
the	O
paths	O
of	O
disconnected	O
nodes	O
when	O
a	O
node	O
fails	O
.	O
</s>
