<s>
In	O
telephony	O
,	O
the	O
demarcation	B-Architecture
point	I-Architecture
is	O
the	O
point	O
at	O
which	O
the	O
public	O
switched	O
telephone	O
network	O
ends	O
and	O
connects	O
with	O
the	O
customer	O
's	O
on-premises	B-Protocol
wiring	I-Protocol
.	O
</s>
<s>
The	O
demarcation	B-Architecture
point	I-Architecture
varies	O
between	O
countries	O
and	O
has	O
changed	O
over	O
time	O
.	O
</s>
<s>
Demarcation	B-Architecture
point	I-Architecture
is	O
sometimes	O
abbreviated	O
as	O
demarc	B-Architecture
,	O
DMARC	O
,	O
or	O
similar	O
.	O
</s>
<s>
The	O
term	O
MPOE	B-Architecture
(	O
minimum	O
or	O
main	O
point	O
of	O
entry	O
)	O
is	O
synonymous	O
,	O
with	O
the	O
added	O
implication	O
that	O
it	O
occurs	O
as	O
soon	O
as	O
possible	O
upon	O
entering	O
the	O
customer	O
premises	O
.	O
</s>
<s>
A	O
network	B-Protocol
interface	I-Protocol
device	I-Protocol
often	O
serves	O
as	O
the	O
demarcation	B-Architecture
point	I-Architecture
.	O
</s>
<s>
Prior	O
to	O
Federal	O
Communications	O
Commission	O
(	O
FCC	O
)	O
regulations	O
separating	O
the	O
ownership	O
of	O
customer	O
premises	O
telecommunication	O
equipment	O
from	O
the	O
telephone	O
network	O
,	O
there	O
was	O
no	O
need	O
for	O
a	O
public	O
standard	O
governing	O
the	O
interconnection	B-Architecture
of	O
customer	O
premises	O
equipment	O
(	O
CPE	O
)	O
to	O
the	O
United	O
States	O
 '	O
telephone	O
network	O
,	O
since	O
both	O
the	O
devices	O
and	O
the	O
“	O
local	O
loop	O
”	O
wiring	O
to	O
the	O
central	O
office	O
were	O
owned	O
and	O
maintained	O
by	O
the	O
local	O
telephone	O
company	O
.	O
</s>
<s>
The	O
physical	O
and	O
electrical	O
interconnection	B-Architecture
is	O
called	O
the	O
demarcation	B-Architecture
point	I-Architecture
,	O
or	O
Demarc	B-Architecture
,	O
which	O
includes	O
one	O
or	O
more	O
customer-accessible	O
jack	O
interfaces	O
;	O
previously	O
,	O
the	O
interface	O
was	O
typically	O
hard-wired	O
and	O
often	O
in	O
a	O
telephone	O
company-owned	O
locked	O
enclosure	O
.	O
</s>
<s>
However	O
,	O
CPE	O
interconnection	B-Architecture
and	O
Bell	O
System	O
divestiture	O
were	O
part	O
of	O
a	O
larger	O
restructuring	O
of	O
the	O
domestic	O
telecommunications	O
industry	O
which	O
took	O
place	O
during	O
the	O
1980s	O
and	O
are	O
commonly	O
,	O
if	O
inaccurately	O
,	O
seen	O
as	O
one	O
event	O
.	O
</s>
<s>
The	O
demarcation	B-Architecture
point	I-Architecture
varies	O
from	O
building	O
type	O
and	O
service	O
level	O
.	O
</s>
<s>
In	O
its	O
simplest	O
form	O
,	O
the	O
demarcation	B-Architecture
point	I-Architecture
is	O
a	O
junction	O
block	O
where	O
telephone	B-Application
extensions	I-Application
join	O
to	O
connect	O
to	O
the	O
network	O
.	O
</s>
<s>
In	O
multi-line	O
installations	O
such	O
as	O
businesses	O
or	O
apartment	O
buildings	O
,	O
the	O
demarcation	B-Architecture
point	I-Architecture
may	O
be	O
a	O
punch	B-Protocol
down	I-Protocol
block	I-Protocol
.	O
</s>
<s>
In	O
the	O
United	O
States	O
,	O
the	O
modern	O
demarcation	B-Architecture
point	I-Architecture
is	O
a	O
device	O
defined	O
by	O
FCC	O
rules	O
(	O
47	O
C.F.R.	O
</s>
<s>
The	O
modern	O
demarcation	B-Architecture
point	I-Architecture
is	O
the	O
network	B-Protocol
interface	I-Protocol
device	I-Protocol
(	O
NID	O
)	O
or	O
intelligent	O
network	B-Protocol
interface	I-Protocol
device	I-Protocol
(	O
INID	O
)	O
also	O
known	O
as	O
a	O
"	O
smartjack	O
"	O
.	O
</s>
<s>
The	O
demarcation	B-Architecture
point	I-Architecture
has	O
a	O
user	O
accessible	O
RJ-11	O
jack	O
(	O
a	O
"	O
test	O
jack	O
"	O
or	O
"	O
demarcation	O
jack	O
"	O
)	O
,	O
which	O
is	O
connected	O
directly	O
to	O
the	O
telephone	O
network	O
,	O
and	O
a	O
small	O
loop	O
of	O
telephone	O
cord	O
connecting	O
to	O
the	O
jack	O
by	O
a	O
modular	B-Architecture
connector	I-Architecture
.	O
</s>
<s>
When	O
the	O
loop	O
is	O
disconnected	O
,	O
the	O
on-premises	B-Protocol
wiring	I-Protocol
is	O
isolated	O
from	O
the	O
telephone	O
network	O
and	O
the	O
customer	O
may	O
directly	O
connect	O
a	O
telephone	O
to	O
the	O
network	O
via	O
the	O
jack	O
to	O
assist	O
in	O
determining	O
the	O
location	O
of	O
a	O
wiring	O
fault	O
.	O
</s>
<s>
In	O
most	O
cases	O
,	O
everything	O
from	O
the	O
central	O
office	O
to	O
and	O
including	O
the	O
demarcation	B-Architecture
point	I-Architecture
is	O
owned	O
by	O
the	O
carrier	O
and	O
everything	O
past	O
it	O
is	O
owned	O
by	O
the	O
property	O
owner	O
.	O
</s>
<s>
As	O
the	O
local	O
loop	O
becomes	O
upgraded	O
,	O
with	O
fiber	B-Architecture
optic	I-Architecture
and	O
coaxial	O
cable	O
technologies	O
sometimes	O
replacing	O
the	O
original	O
unshielded	O
twisted	O
pair	O
to	O
the	O
premises	O
,	O
the	O
demarcation	B-Architecture
point	I-Architecture
has	O
grown	O
to	O
incorporate	O
the	O
equipment	O
necessary	O
to	O
interface	O
the	O
original	O
premises	O
POTS	O
wiring	O
and	O
equipment	O
to	O
the	O
new	O
communication	O
channel	O
.	O
</s>
<s>
Demarcation	B-Architecture
points	I-Architecture
on	O
houses	O
built	O
prior	O
to	O
the	O
Bell	O
System	O
divestiture	O
usually	O
do	O
not	O
contain	O
a	O
test	O
jack	O
.	O
</s>
<s>
DEMARCs	B-Architecture
that	O
handle	O
both	O
telephony	O
and	O
IT	O
fiber	B-Architecture
optic	I-Architecture
internet	O
lines	O
often	O
do	O
not	O
look	O
like	O
the	O
ones	O
pictured	O
above	O
.	O
</s>
<s>
In	O
many	O
places	O
several	O
customers	O
share	O
one	O
central	O
DEMARC	B-Architecture
for	O
a	O
commercial	O
or	O
strip	O
mall	O
setting	O
.	O
</s>
<s>
Usually	O
a	O
DEMARC	B-Architecture
will	O
be	O
located	O
indoors	O
if	O
it	O
is	O
serving	O
more	O
than	O
a	O
single	O
customer	O
.	O
</s>
<s>
Typically	O
indoor	O
DEMARC	B-Architecture
's	O
will	O
be	O
easily	O
identified	O
by	O
a	O
patch	B-Protocol
panel	I-Protocol
of	O
telephone	O
wires	O
on	O
the	O
wall	O
next	O
to	O
a	O
series	O
of	O
boxes	O
with	O
RJ48	O
jacks	O
for	O
T-1	O
lines	O
.	O
</s>
<s>
A	O
demarcation	B-Architecture
point	I-Architecture
extension	I-Architecture
,	O
or	O
demarc	B-Architecture
extension	I-Architecture
is	O
the	O
transmission	O
path	O
originating	O
from	O
the	O
interface	O
of	O
the	O
access	O
provider	O
's	O
side	O
of	O
a	O
demarcation	B-Architecture
point	I-Architecture
within	O
a	O
premises	O
and	O
ending	O
at	O
the	O
termination	O
point	O
prior	O
to	O
the	O
interface	O
of	O
the	O
edge	O
Customer	O
Premises	O
Equipment	O
(	O
CPE	O
)	O
.	O
</s>
<s>
A	O
demarc	B-Architecture
extension	I-Architecture
is	O
more	O
correctly	O
termed	O
"	O
Service	O
Interface	O
Extension	O
"	O
,	O
and	O
may	O
also	O
be	O
referred	O
to	O
as	O
inside	B-Protocol
wiring	I-Protocol
,	O
extended	O
demarc	B-Architecture
,	O
circuit	O
extension	O
,	O
CPE	O
cabling	O
,	O
riser	O
cabling	O
or	O
DMARC	O
extension	O
.	O
</s>
<s>
A	O
demarc	B-Architecture
extension	I-Architecture
became	O
an	O
important	O
factor	O
to	O
consider	O
in	O
a	O
building	O
's	O
telecommunications	O
infrastructure	O
after	O
the	O
1984	O
deregulation	O
of	O
AT&T	O
as	O
well	O
as	O
the	O
supplemental	O
FCC	O
rulings	O
of	O
1991	O
,	O
1996	O
and	O
1997	O
.	O
</s>
<s>
Preceding	O
these	O
rulings	O
,	O
the	O
Bell	O
System	O
Companies	O
held	O
a	O
monopoly	O
and	O
did	O
not	O
allow	O
an	O
interconnection	B-Architecture
with	O
third	O
party	O
equipment	O
.	O
</s>
<s>
This	O
separation	O
between	O
the	O
local	O
access	O
provider	O
and	O
the	O
end	O
user/subscriber	O
is	O
called	O
the	O
demarcation	B-Architecture
point	I-Architecture
within	O
a	O
facility	O
(	O
typically	O
a	O
short	O
distance	O
from	O
the	O
minimum	B-Architecture
point	I-Architecture
of	I-Architecture
entry	I-Architecture
)	O
.	O
</s>
<s>
This	O
then	O
becomes	O
the	O
responsibility	O
of	O
the	O
end	O
user	O
to	O
extend	O
their	O
service	O
to	O
the	O
CPE	O
location	O
within	O
a	O
facility	O
to	O
provide	O
connectivity	O
for	O
service	O
,	O
requiring	O
a	O
service	O
interface	O
extension	O
,	O
or	O
otherwise	O
called	O
a	O
demarc	B-Architecture
extension	I-Architecture
.	O
</s>
<s>
In	O
the	O
United	O
Kingdom	O
,	O
the	O
demarcation	B-Architecture
point	I-Architecture
occurs	O
on	O
the	O
LJU	O
master	O
socket	O
,	O
whose	O
wiring	O
is	O
partly	O
owned	O
by	O
the	O
customer	O
,	O
partly	O
owned	O
by	O
the	O
phone	O
company	O
.	O
</s>
