<s>
Collaborative	B-Operating_System
virtual	I-Operating_System
environments	I-Operating_System
are	O
used	O
for	O
collaboration	O
and	O
interaction	O
of	O
possibly	O
many	O
participants	O
that	O
may	O
be	O
spread	O
over	O
large	O
distances	O
.	O
</s>
<s>
Because	O
of	O
the	O
spreading	O
of	O
participants	O
and	O
the	O
communication	O
latency	O
,	O
some	O
data	O
consistency	B-General_Concept
model	I-General_Concept
have	O
to	O
be	O
used	O
to	O
keep	O
the	O
data	O
consistent	O
.	O
</s>
<s>
The	O
consistency	B-General_Concept
model	I-General_Concept
influences	O
deeply	O
the	O
programming	O
model	O
of	O
the	O
application	O
.	O
</s>
<s>
Four	O
types	O
of	O
consistency	B-General_Concept
models	I-General_Concept
were	O
described	O
,	O
covering	O
the	O
most	O
frequently	O
used	O
types	O
of	O
collaborative	B-Operating_System
virtual	I-Operating_System
environment	I-Operating_System
architecture	O
:	O
</s>
<s>
Collaborative	B-Operating_System
virtual	I-Operating_System
environment	I-Operating_System
architectures	O
:	O
</s>
<s>
Used	O
in	O
:	O
Distributed	B-Operating_System
Interactive	I-Operating_System
Simulation	I-Operating_System
,	O
Repo-3D	O
,	O
</s>
<s>
Used	O
in	O
:	O
active	O
transactions	O
,	O
Age	B-Application
of	I-Application
Empires	I-Application
,	O
,	O
</s>
