<s>
In	O
telecommunications	O
business	O
,	O
a	O
white	B-Protocol
route	I-Protocol
is	O
a	O
route	O
where	O
both	O
source	O
and	O
destination	O
are	O
legal	O
termination	O
.	O
</s>
<s>
This	O
is	O
opposed	O
to	O
a	O
black	B-Protocol
route	I-Protocol
,	O
which	O
is	O
a	O
route	O
that	O
is	O
illegal	O
in	O
both	O
ends	O
.	O
</s>
<s>
Also	O
common	O
in	O
telecom	O
(	O
especially	O
VoIP	B-Application
)	O
is	O
the	O
term	O
grey	B-Protocol
route	I-Protocol
,	O
which	O
defines	O
a	O
route	O
that	O
is	O
legal	O
for	O
one	O
country	O
or	O
the	O
party	O
on	O
one	O
end	O
,	O
but	O
illegal	O
on	O
the	O
alternative	O
end	O
.	O
</s>
<s>
To	O
overcome	O
this	O
restriction	O
for	O
the	O
purpose	O
of	O
achieving	O
lower	O
costs	O
for	O
consumers	O
,	O
and	O
to	O
make	O
a	O
profit	O
in	O
the	O
process	O
,	O
many	O
small	O
parties	O
set	O
up	O
VoIP	B-Application
routers	O
in	O
homes	O
and	O
offices	O
around	O
India	O
.	O
</s>
<s>
Telecom	O
traffic	O
from	O
other	O
countries	O
is	O
sent	O
to	O
these	O
VoIP	B-Application
routers	O
via	O
IP	B-Protocol
and	O
terminated	O
to	O
the	O
local	O
Indian	O
PSTN	O
.	O
</s>
<s>
A	O
"	O
SIM	O
box	O
"	O
is	O
an	O
unofficial	O
voice	B-Application
over	I-Application
IP	I-Application
gateway	O
which	O
uses	O
multiple	O
mobile	O
telephones	O
and	O
SIM	O
cards	O
for	O
PSTN	O
connectivity	O
,	O
while	O
connecting	O
to	O
the	O
Internet	O
by	O
conventional	O
means	O
.	O
</s>
<s>
These	O
are	O
normally	O
operated	O
clandestinely	O
in	O
third-world	O
calling	O
destinations	O
as	O
the	O
"	O
black	O
"	O
end	O
of	O
a	O
"	O
grey	B-Protocol
route	I-Protocol
"	O
where	O
conventional	O
private	B-Device
branch	I-Device
exchange	I-Device
lines	O
(	O
such	O
as	O
T-carrier	O
primary	B-Protocol
rate	I-Protocol
interface	I-Protocol
)	O
are	O
not	O
available	O
to	O
VoIP	B-Application
operators	O
due	O
to	O
a	O
hostile	O
local	O
regulatory	O
environment	O
.	O
</s>
