<s>
A	O
population	B-Operating_System
protocol	I-Operating_System
is	O
a	O
distributed	B-Architecture
computing	I-Architecture
model	O
formed	O
by	O
resource-limited	O
mobile	O
agents	O
which	O
meet	O
in	O
a	O
random	O
way	O
according	O
to	O
an	O
interaction	O
graph	O
.	O
</s>
<s>
Functions	O
are	O
computed	O
by	O
updating	O
the	O
state	O
of	O
agents	O
whenever	O
they	O
meet	O
based	O
on	O
their	O
previous	O
state	O
,	O
and	O
the	O
result	O
of	O
the	O
computation	O
can	O
be	O
read	O
in	O
the	O
states	O
of	O
the	O
agents	O
once	O
the	O
computation	O
has	O
converged	B-Algorithm
.	O
</s>
<s>
An	O
important	O
class	O
of	O
population	B-Operating_System
protocols	I-Operating_System
are	O
majority	O
algorithms	O
,	O
where	O
the	O
goal	O
is	O
to	O
compute	O
the	O
majority	O
bit	O
:	O
each	O
node	O
starts	O
with	O
a	O
belief	O
bit	O
in	O
and	O
the	O
goal	O
is	O
to	O
design	O
a	O
protocol	O
at	O
the	O
end	O
of	O
which	O
the	O
belief	O
bit	O
of	O
every	O
node	O
is	O
the	O
correct	O
initial	O
majority	O
bit	O
.	O
</s>
<s>
Protocols	O
are	O
often	O
designed	O
to	O
minimize	O
the	O
convergence	B-Algorithm
time	O
or	O
the	O
amount	O
of	O
memory	O
required	O
per	O
node	O
or	O
both	O
.	O
</s>
<s>
Population	B-Operating_System
protocols	I-Operating_System
were	O
introduced	O
by	O
Dana	O
Angluin	O
et	O
al	O
.	O
</s>
<s>
as	O
one	O
of	O
the	O
first	O
models	O
of	O
computation	O
to	O
be	O
fully	O
decentralized	O
and	O
to	O
involve	O
agents	O
with	O
highly	O
limited	O
resources	O
,	O
e.g.	O
,	O
those	O
found	O
in	O
sensor	B-Architecture
networks	I-Architecture
.	O
</s>
