<s>
A	O
modular	B-Architecture
connector	I-Architecture
is	O
a	O
type	O
of	O
electrical	B-Protocol
connector	I-Protocol
for	O
cords	O
and	O
cables	O
of	O
electronic	O
devices	O
and	O
appliances	O
,	O
such	O
as	O
in	O
computer	B-Architecture
networking	I-Architecture
,	O
telecommunication	O
equipment	O
,	O
and	O
audio	O
headsets	B-Device
.	O
</s>
<s>
Modular	B-Architecture
connectors	I-Architecture
were	O
originally	O
developed	O
for	O
use	O
on	O
specific	O
Bell	O
System	O
telephone	O
sets	O
in	O
the	O
1960s	O
,	O
and	O
similar	O
types	O
found	O
use	O
for	O
simple	O
interconnection	O
of	O
customer-provided	O
telephone	O
subscriber	O
premises	O
equipment	O
to	O
the	O
telephone	O
network	O
.	O
</s>
<s>
The	O
Federal	O
Communications	O
Commission	O
(	O
FCC	O
)	O
mandated	O
in	O
1976	O
an	O
interface	O
registration	O
system	O
,	O
in	O
which	O
they	O
became	O
known	O
as	O
registered	B-Protocol
jacks	I-Protocol
.	O
</s>
<s>
The	O
convenience	O
of	O
prior	O
existence	O
for	O
designers	O
and	O
ease	O
of	O
use	O
led	O
to	O
a	O
proliferation	O
of	O
modular	B-Architecture
connectors	I-Architecture
for	O
many	O
other	O
applications	O
.	O
</s>
<s>
Many	O
applications	O
that	O
originally	O
used	O
bulkier	O
,	O
more	O
expensive	O
connectors	O
have	O
converted	O
to	O
modular	B-Architecture
connectors	I-Architecture
.	O
</s>
<s>
Probably	O
the	O
best-known	O
applications	O
of	O
modular	B-Architecture
connectors	I-Architecture
are	O
for	O
telephone	O
and	O
Ethernet	O
.	O
</s>
<s>
Accordingly	O
,	O
various	O
electronic	O
interface	O
specifications	O
exist	O
for	O
applications	O
using	O
modular	B-Architecture
connectors	I-Architecture
,	O
which	O
prescribe	O
physical	O
characteristics	O
and	O
assign	O
electrical	O
signals	O
to	O
their	O
contacts	O
.	O
</s>
<s>
Modular	B-Architecture
connectors	I-Architecture
are	O
often	O
referred	O
to	O
as	O
modular	O
phone	O
jack	O
and	O
plug	O
,	O
RJ	B-Protocol
connector	I-Protocol
,	O
and	O
Western	B-Protocol
jack	I-Protocol
and	O
plug	O
.	O
</s>
<s>
The	O
term	O
modular	B-Architecture
connector	I-Architecture
arose	O
from	O
its	O
original	O
use	O
in	O
modular	O
wiring	O
components	O
of	O
telephone	O
equipment	O
by	O
the	O
Western	O
Electric	O
Company	O
in	O
the	O
1960s	O
.	O
</s>
<s>
This	O
includes	O
the	O
6P2C	O
used	O
for	O
telephone	B-Protocol
line	I-Protocol
connections	I-Protocol
and	O
4P4C	O
used	O
for	O
handset	O
connectors	O
.	O
</s>
<s>
Registered	B-Protocol
jack	I-Protocol
designations	O
describe	O
the	O
signals	O
and	O
wiring	O
used	O
for	O
voice	O
and	O
data	O
communication	O
at	O
customer-facing	O
interfaces	O
of	O
the	O
public	O
switched	O
telephone	O
network	O
.	O
</s>
<s>
It	O
is	O
common	O
to	O
use	O
a	O
registered	B-Protocol
jack	I-Protocol
number	O
to	O
refer	O
to	O
the	O
physical	O
connector	O
itself	O
;	O
for	O
instance	O
,	O
the	O
8P8C	O
modular	B-Architecture
connector	I-Architecture
type	O
is	O
often	O
labeled	O
RJ45	O
because	O
the	O
registered	B-Protocol
jack	I-Protocol
standard	O
of	O
that	O
name	O
specified	O
8P8C	O
modular	B-Architecture
connectors	I-Architecture
.	O
</s>
<s>
Similarly	O
,	O
various	O
six-position	O
modular	B-Architecture
connectors	I-Architecture
may	O
be	O
called	O
RJ11	O
.	O
</s>
<s>
In	O
1976	O
,	O
these	O
connectors	O
were	O
standardized	O
nationally	O
in	O
the	O
United	O
States	O
by	O
the	O
Registration	O
Interface	O
program	O
of	O
the	O
Federal	O
Communications	O
Commission	O
(	O
FCC	O
)	O
,	O
which	O
designated	O
a	O
series	O
of	O
Registered	B-Protocol
Jack	I-Protocol
(	O
RJ	O
)	O
specifications	O
for	O
interconnection	O
of	O
customer-premises	O
equipment	O
to	O
the	O
public	O
switched	O
telephone	O
network	O
(	O
PSTN	O
)	O
.	O
</s>
<s>
Modular	B-Architecture
connectors	I-Architecture
have	O
gender	O
:	O
plugs	B-Protocol
are	O
considered	O
to	O
be	O
male	O
,	O
while	O
jacks	O
or	O
sockets	O
are	O
considered	O
to	O
be	O
female	O
.	O
</s>
<s>
Plugs	B-Protocol
are	O
used	O
to	O
terminate	O
cables	O
and	O
cords	O
,	O
while	O
jacks	O
are	O
used	O
for	O
fixed	O
locations	O
on	O
surfaces	O
of	O
walls	O
,	O
panels	O
,	O
and	O
equipment	O
.	O
</s>
<s>
Other	O
than	O
telephone	O
extension	O
cables	O
,	O
cables	O
with	O
a	O
modular	B-Architecture
plug	I-Architecture
on	O
one	O
end	O
and	O
a	O
jack	O
on	O
the	O
other	O
are	O
rare	O
.	O
</s>
<s>
Most	O
modular	B-Architecture
connectors	I-Architecture
are	O
designed	O
with	O
a	O
latching	O
mechanism	O
that	O
secures	O
the	O
physical	O
connection	O
.	O
</s>
<s>
The	O
modular	B-Architecture
plug	I-Architecture
is	O
often	O
installed	O
with	O
a	O
boot	O
,	O
a	O
plastic	O
covering	O
over	O
the	O
tab	O
and	O
body	O
,	O
to	O
prevent	O
the	O
latching	O
tab	O
to	O
hook	O
into	O
other	O
cords	O
or	O
edges	O
,	O
which	O
may	O
cause	O
excessive	O
bending	O
or	O
breaking	O
of	O
the	O
tab	O
.	O
</s>
<s>
Such	O
cords	O
,	O
are	O
usually	O
constructed	O
by	O
installing	O
the	O
protective	O
boot	O
before	O
the	O
modular	B-Architecture
plug	I-Architecture
is	O
crimped	O
.	O
</s>
<s>
Modular	B-Architecture
connectors	I-Architecture
are	O
designated	O
using	O
two	O
numbers	O
that	O
represent	O
the	O
maximum	O
number	O
of	O
contact	B-Protocol
positions	O
and	O
the	O
number	O
of	O
installed	O
contacts	O
,	O
with	O
each	O
number	O
followed	O
by	O
P	O
and	O
C	O
,	O
respectively	O
.	O
</s>
<s>
Alternate	O
designations	O
omit	O
the	O
letters	O
while	O
separating	O
the	O
position	O
and	O
contact	B-Protocol
quantities	O
with	O
either	O
an	O
x	O
(	O
6x2	O
)	O
or	O
a	O
slash	O
(	O
6/2	O
)	O
.	O
</s>
<s>
The	O
connector	O
body	O
positions	O
with	O
omitted	O
or	O
unconnected	O
contacts	O
are	O
unused	O
for	O
the	O
electrical	B-Protocol
connection	I-Protocol
but	O
ensure	O
that	O
the	O
plug	O
fits	O
correctly	O
.	O
</s>
<s>
The	O
contact	B-Protocol
positions	O
are	O
numbered	O
sequentially	O
starting	O
from	O
1	O
.	O
</s>
<s>
When	O
viewed	O
head-on	O
with	O
the	O
retention	O
mechanism	O
on	O
the	O
bottom	O
,	O
jacks	O
will	O
have	O
contact	B-Protocol
position	O
number	O
1	O
on	O
the	O
left	O
and	O
plugs	B-Protocol
will	O
have	O
it	O
on	O
the	O
right	O
.	O
</s>
<s>
Contacts	O
are	O
numbered	O
by	O
the	O
contact	B-Protocol
position	O
.	O
</s>
<s>
For	O
example	O
,	O
on	O
a	O
six-position	O
,	O
two-contact	O
plug	O
,	O
where	O
the	O
outermost	O
four	O
positions	O
do	O
not	O
have	O
contacts	O
,	O
the	O
innermost	O
two	O
contacts	O
are	O
numbered	O
3	O
and	O
4	O
.	O
</s>
<s>
Modular	B-Architecture
connectors	I-Architecture
are	O
manufactured	O
in	O
four	O
sizes	O
,	O
with	O
4-	O
,	O
6-	O
,	O
8-	O
,	O
and	O
10-positions	O
.	O
</s>
<s>
Internally	O
,	O
the	O
contacts	O
on	O
the	O
plugs	B-Protocol
have	O
sharp	O
prongs	O
that	O
,	O
when	O
crimped	O
,	O
pierce	O
the	O
wire	O
insulation	O
and	O
connect	O
with	O
the	O
conductor	O
,	O
a	O
mechanism	O
known	O
as	O
insulation	B-Protocol
displacement	I-Protocol
.	O
</s>
<s>
A	O
modular	B-Architecture
plug	I-Architecture
for	O
solid	O
(	O
single-strand	O
)	O
wire	O
often	O
has	O
three	O
slightly	O
splayed	O
prongs	O
on	O
each	O
contact	B-Protocol
to	O
securely	O
surround	O
and	O
grip	O
the	O
conductor	O
.	O
</s>
<s>
Modular	B-Architecture
plugs	I-Architecture
for	O
stranded	O
have	O
prongs	O
that	O
are	O
designed	O
to	O
connect	O
to	O
multiple	O
wire	O
strands	O
.	O
</s>
<s>
Connector	O
plugs	B-Protocol
are	O
designed	O
for	O
either	O
solid	O
or	O
stranded	O
wire	O
and	O
a	O
mismatch	O
between	O
plug	O
and	O
wire	O
type	O
may	O
result	O
in	O
an	O
unreliable	O
connection	O
.	O
</s>
<s>
Some	O
modular	B-Architecture
connectors	I-Architecture
are	O
indexed	O
,	O
meaning	O
their	O
dimensions	O
are	O
intentionally	O
non-standard	O
,	O
preventing	O
connections	O
with	O
connectors	O
of	O
standard	O
dimensions	O
.	O
</s>
<s>
For	O
example	O
,	O
a	O
Modified	B-Device
Modular	I-Device
Jack	I-Device
using	O
an	O
offset	O
latching	O
tab	O
was	O
developed	O
by	O
Digital	O
Equipment	O
Corporation	O
to	O
prevent	O
accidental	O
interchange	O
of	O
data	O
and	O
telephone	O
cables	O
.	O
</s>
<s>
The	O
dimensions	O
of	O
modular	B-Architecture
connectors	I-Architecture
are	O
such	O
that	O
a	O
narrower	O
plug	O
can	O
be	O
inserted	O
into	O
a	O
wider	O
jack	O
that	O
has	O
more	O
positions	O
than	O
the	O
plug	O
,	O
leaving	O
the	O
jack	O
's	O
outermost	O
contacts	O
unconnected	O
.	O
</s>
<s>
The	O
height	O
of	O
the	O
plug	O
's	O
insertion	O
area	O
is	O
0.260inches	O
(	O
6.60mm	O
)	O
and	O
the	O
contacts	O
are	O
0.040inches	O
(	O
1.02mm	O
)	O
apart	O
(	O
contact	B-Protocol
pitch	O
)	O
,	O
so	O
the	O
width	O
is	O
dependent	O
on	O
the	O
number	O
of	O
pin	O
positions	O
.	O
</s>
<s>
However	O
,	O
not	O
all	O
plugs	B-Protocol
from	O
all	O
manufacturers	O
have	O
this	O
capability	O
,	O
and	O
some	O
jack	O
manufacturers	O
warn	O
that	O
their	O
jacks	O
are	O
not	O
designed	O
to	O
accept	O
smaller	O
plugs	B-Protocol
without	O
damage	O
.	O
</s>
<s>
Special	O
modular	B-Architecture
plugs	I-Architecture
have	O
been	O
manufactured	O
(	O
for	O
example	O
,	O
the	O
Siemon	O
UP-2468	O
)	O
which	O
have	O
extra	O
slots	O
beyond	O
their	O
standard	O
contacts	O
,	O
to	O
accommodate	O
the	O
wider	O
jack	O
's	O
outermost	O
contacts	O
without	O
damage	O
.	O
</s>
<s>
The	O
molded	O
plastic	O
bodies	O
of	O
the	O
special	O
plugs	B-Protocol
may	O
also	O
be	O
colored	O
with	O
a	O
light	O
blueish	O
tinge	O
,	O
to	O
aid	O
in	O
quick	O
recognition	O
.	O
</s>
<s>
The	O
special	O
plugs	B-Protocol
are	O
preferred	O
for	O
test	O
equipment	O
and	O
adapters	O
,	O
which	O
may	O
be	O
rapidly	O
connected	O
to	O
a	O
large	O
number	O
of	O
corresponding	O
connectors	O
in	O
quick	O
succession	O
for	O
testing	O
purposes	O
.	O
</s>
<s>
The	O
use	O
of	O
the	O
special	O
plugs	B-Protocol
avoids	O
inadvertent	O
damage	O
to	O
the	O
equipment	O
under	O
test	O
,	O
even	O
when	O
a	O
narrower	O
plug	O
is	O
inserted	O
into	O
a	O
nominally	O
incompatible	O
wider	O
jack	O
.	O
</s>
<s>
Termination	O
of	O
cables	O
with	O
modular	B-Architecture
connectors	I-Architecture
is	O
similar	O
across	O
the	O
various	O
number	O
of	O
positions	O
and	O
contacts	O
in	O
the	O
plug	O
.	O
</s>
<s>
The	O
crimping	O
tool	O
contains	O
a	O
die	O
which	O
is	O
often	O
exchangeable	O
and	O
is	O
closely	O
matched	O
to	O
the	O
shape	O
and	O
pin	O
count	O
of	O
the	O
modular	B-Architecture
plug	I-Architecture
.	O
</s>
<s>
The	O
contact	B-Protocol
assignments	O
(	O
pinout	B-Application
)	O
of	O
modular	B-Architecture
connectors	I-Architecture
vary	O
by	O
application	O
.	O
</s>
<s>
Telephone	O
network	O
connections	O
are	O
standardized	O
by	O
registered	B-Protocol
jack	I-Protocol
designations	O
,	O
and	O
Ethernet	B-Protocol
over	I-Protocol
twisted	I-Protocol
pair	I-Protocol
is	O
specified	O
by	O
the	O
ANSI/TIA	O
-568	O
standard	O
.	O
</s>
<s>
For	O
this	O
reason	O
,	O
D-sub-to-modular	O
adapters	O
are	O
typically	O
shipped	O
with	O
the	O
D-sub	B-Protocol
contacts	O
(	O
pins	O
or	O
sockets	O
)	O
terminated	O
but	O
not	O
inserted	O
into	O
the	O
connector	O
body	O
,	O
so	O
that	O
the	O
D-sub-to-modular	O
contact	B-Protocol
pairing	O
can	O
be	O
assigned	O
as	O
needed	O
.	O
</s>
<s>
The	O
four-position	O
four-conductor	O
(	O
4P4C	O
)	O
connector	O
is	O
the	O
standard	O
modular	B-Architecture
connector	I-Architecture
used	O
on	O
both	O
ends	O
of	O
telephone	O
handset	O
cords	O
,	O
and	O
is	O
therefore	O
often	O
called	O
a	O
handset	O
connector	O
.	O
</s>
<s>
This	O
handset	O
connector	O
is	O
not	O
a	O
registered	B-Protocol
jack	I-Protocol
,	O
because	O
it	O
was	O
not	O
intended	O
to	O
connect	O
directly	O
to	O
telephone	O
lines	O
.	O
</s>
<s>
Handsets	O
and	O
often	O
headsets	B-Device
for	O
use	O
with	O
telephones	O
commonly	O
use	O
a	O
4P4C	O
connector	O
.	O
</s>
<s>
This	O
may	O
differ	O
for	O
other	O
equipment	O
,	O
including	O
hands-free	O
headsets	B-Device
.	O
</s>
<s>
The	O
Macintosh	B-Device
128K	I-Device
,	O
Macintosh	B-Device
512K	I-Device
and	O
Macintosh	B-Device
Plus	I-Device
from	O
Apple	O
as	O
well	O
as	O
the	O
Amiga	B-Device
1000	I-Device
from	O
Commodore	O
used	O
4P4C	O
connectors	O
to	O
connect	O
the	O
keyboard	O
to	O
the	O
main	O
computer	O
housing	O
.	O
</s>
<s>
The	O
connector	O
on	O
the	O
Amiga	B-Device
1000	I-Device
used	O
crossover	O
wiring	O
,	O
similar	O
to	O
a	O
telephone	O
handset	O
.	O
</s>
<s>
The	O
connector	O
wiring	O
on	O
the	O
Apple	O
computers	O
,	O
however	O
,	O
required	O
a	O
polarized	O
straight	O
through	O
pinout	B-Application
.	O
</s>
<s>
Modular	B-Architecture
connectors	I-Architecture
are	O
often	O
used	O
for	O
data	O
links	O
,	O
such	O
as	O
serial	O
line	O
connections	O
,	O
because	O
of	O
their	O
compact	O
dimensions	O
.	O
</s>
<s>
Modular	B-Architecture
plugs	I-Architecture
are	O
described	O
by	O
the	O
maximum	O
number	O
of	O
physical	O
contact	B-Protocol
positions	O
and	O
the	O
actual	O
number	O
of	O
contacts	O
installed	O
in	O
these	O
positions	O
.	O
</s>
<s>
The	O
6P2C	O
,	O
6P4C	O
,	O
and	O
6P6C	O
modular	B-Architecture
connectors	I-Architecture
are	O
probably	O
best	O
known	O
for	O
their	O
use	O
as	O
RJ11	O
,	O
RJ14	O
,	O
and	O
RJ25	O
registered	B-Protocol
jacks	I-Protocol
,	O
respectively	O
.	O
</s>
<s>
These	O
interfaces	O
use	O
the	O
same	O
six-position	O
modular	B-Architecture
connector	I-Architecture
body	O
,	O
but	O
have	O
different	O
numbers	O
of	O
pins	O
installed	O
.	O
</s>
<s>
RJ61	O
is	O
a	O
similar	O
registered	B-Protocol
jack	I-Protocol
for	O
four	O
lines	O
,	O
but	O
uses	O
an	O
8P8C	O
connector	O
.	O
</s>
<s>
Two	O
of	O
its	O
six	O
possible	O
contact	B-Protocol
positions	O
connect	O
tip	O
and	O
ring	O
,	O
and	O
the	O
other	O
two	O
contact	B-Protocol
positions	O
may	O
be	O
unused	O
or	O
provide	O
low-voltage	O
power	O
for	O
night-light	O
or	O
other	O
features	O
on	O
the	O
telephone	O
set	O
.	O
</s>
<s>
In	O
some	O
installations	O
an	O
extra	O
contact	B-Protocol
was	O
also	O
required	O
for	O
the	O
ground	O
connection	O
for	O
selective	B-Architecture
ringers	I-Architecture
.	O
</s>
<s>
However	O
,	O
with	O
German	O
domestic	O
telephone	O
equipment	O
,	O
and	O
that	O
in	O
some	O
neighboring	O
countries	O
,	O
6P4C	O
plugs	B-Protocol
and	O
sockets	O
are	O
typically	O
only	O
used	O
to	O
connect	O
the	O
telephone	O
cord	O
to	O
the	O
phone	O
base	O
unit	O
,	O
whereas	O
the	O
mechanically	O
different	O
TAE	B-Protocol
connector	I-Protocol
is	O
used	O
at	O
the	O
other	O
end	O
to	O
connect	O
to	O
a	O
service	O
provider	O
interface	O
.	O
</s>
<s>
Older	O
base	O
units	O
may	O
accommodate	O
the	O
additional	O
connectors	O
of	O
TAE	O
(	O
E	O
,	O
W	O
,	O
a2	O
,	O
b2	O
)	O
and	O
may	O
feature	O
non-RJ	O
standard	O
sockets	O
that	O
can	O
be	O
connected	O
directly	O
to	O
TAE	O
plugs	B-Protocol
.	O
</s>
<s>
When	O
used	O
directly	O
with	O
6P4C	O
plugs	B-Protocol
,	O
the	O
color	O
coding	O
may	O
be	O
undetermined	O
.	O
</s>
<s>
Structured	O
cabling	O
networks	O
adhering	O
to	O
ANSI/TIA	O
-568	O
,	O
ISO/IEC	O
11801	O
(	O
or	O
ISO/IEC	O
15018	O
for	O
home	O
networks	O
)	O
are	O
widely	O
used	O
for	O
both	O
computer	B-Architecture
networking	I-Architecture
and	O
analog	O
telephony	O
.	O
</s>
<s>
The	O
8	O
position	O
8	O
contact	B-Protocol
(	O
8P8C	O
)	O
connector	O
is	O
a	O
modular	B-Architecture
connector	I-Architecture
commonly	O
used	O
to	O
terminate	O
twisted	O
pair	O
and	O
multi-conductor	O
flat	O
cable	O
.	O
</s>
<s>
These	O
connectors	O
are	O
commonly	O
used	O
for	O
Ethernet	B-Protocol
over	I-Protocol
twisted	I-Protocol
pair	I-Protocol
,	O
registered	B-Protocol
jacks	I-Protocol
and	O
other	O
telephone	O
applications	O
,	O
RS-232	O
serial	O
communication	O
using	O
the	O
ANSI/TIA	O
-568	O
(	O
formerly	O
TIA/EIA	O
-568	O
)	O
and	O
Yost	O
standards	O
,	O
and	O
other	O
applications	O
involving	O
unshielded	O
twisted	O
pair	O
,	O
shielded	O
twisted	O
pair	O
,	O
and	O
multi-conductor	O
flat	O
cable	O
.	O
</s>
<s>
When	O
the	O
plug	O
is	O
mated	O
with	O
the	O
jack	O
,	O
the	O
contacts	O
meet	O
and	O
create	O
an	O
electrical	B-Protocol
connection	I-Protocol
.	O
</s>
<s>
Although	O
commonly	O
referred	O
to	O
as	O
RJ45	O
in	O
the	O
context	O
of	O
Ethernet	O
and	O
category	B-Protocol
5	I-Protocol
cables	I-Protocol
,	O
RJ45	O
originally	O
referred	O
to	O
a	O
specific	O
wiring	O
configuration	O
of	O
an	O
8P8C	O
connector	O
.	O
</s>
<s>
The	O
RJ45S	O
jack	O
mates	O
with	O
a	O
keyed	O
8P2C	O
modular	B-Architecture
plug	I-Architecture
,	O
and	O
has	O
pins	O
4	O
and	O
5	O
(	O
the	O
middle	O
positions	O
)	O
wired	O
for	O
the	O
ring	O
and	O
tip	O
conductors	O
of	O
a	O
single	O
telephone	O
line	O
and	O
pins	O
7	O
and	O
8	O
shorting	O
a	O
programming	O
resistor	O
.	O
</s>
<s>
Generic	O
8P8C	O
modular	B-Architecture
connectors	I-Architecture
are	O
similar	O
to	O
those	O
used	O
for	O
the	O
RJ45S	O
variant	O
,	O
although	O
the	O
RJ45S	O
plug	O
is	O
keyed	O
and	O
not	O
compatible	O
with	O
non-keyed	O
8P8C	O
modular	B-Architecture
jacks	I-Architecture
.	O
</s>
<s>
Telephone	O
installers	O
who	O
wired	O
RJ45S	O
modem	O
jacks	O
or	O
RJ61X	O
telephone	B-Protocol
jacks	I-Protocol
were	O
familiar	O
with	O
the	O
pin	O
assignments	O
of	O
the	O
standard	O
.	O
</s>
<s>
However	O
,	O
the	O
standard	O
un-keyed	O
modular	B-Architecture
connectors	I-Architecture
became	O
ubiquitous	O
for	O
computer	B-Architecture
networking	I-Architecture
and	O
informally	O
inherited	O
the	O
name	O
RJ45	O
.	O
</s>
<s>
The	O
shape	O
and	O
dimensions	O
of	O
an	O
8P8C	O
modular	B-Architecture
connector	I-Architecture
are	O
specified	O
for	O
US	O
telephone	O
applications	O
by	O
the	O
Administrative	O
Council	O
for	O
Terminal	O
Attachment	O
(	O
ACTA	O
)	O
in	O
national	O
standard	O
ANSI/TIA	O
-1096-A	O
and	O
international	O
standard	O
ISO-8877	O
.	O
</s>
<s>
This	O
standard	O
does	O
not	O
use	O
the	O
short	O
term	O
8P8C	O
and	O
covers	O
more	O
than	O
just	O
8P8C	O
modular	B-Architecture
connectors	I-Architecture
,	O
but	O
the	O
8P8C	O
modular	B-Architecture
connector	I-Architecture
type	O
is	O
the	O
eight	O
position	O
connector	O
type	O
described	O
therein	O
,	O
with	O
eight	O
contacts	O
installed	O
.	O
</s>
<s>
For	O
data	O
communication	O
applications	O
(	O
LAN	B-General_Concept
,	O
structured	O
cabling	O
)	O
,	O
International	O
Standard	O
IEC	O
60603	O
specifies	O
in	O
parts	O
7-1	O
,	O
7-2	O
,	O
7-4	O
,	O
7-5	O
,	O
and	O
7-7	O
not	O
only	O
the	O
same	O
physical	O
dimensions	O
but	O
also	O
high-frequency	O
performance	O
requirements	O
for	O
shielded	O
and	O
unshielded	O
versions	O
of	O
this	O
connector	O
for	O
carrying	O
frequencies	O
up	O
to	O
100	O
,	O
250	O
and	O
600MHz	O
.	O
</s>
<s>
A	O
cable	O
wired	O
as	O
T568A	O
at	O
one	O
end	O
and	O
wired	O
as	O
T568B	O
at	O
the	O
other	O
end	O
(	O
Tx	O
and	O
Rx	O
pairs	O
reversed	O
)	O
is	O
an	O
Ethernet	B-Protocol
crossover	I-Protocol
cable	I-Protocol
.	O
</s>
<s>
Before	O
the	O
widespread	O
acceptance	O
of	O
auto	O
MDI-X	O
capabilities	O
,	O
a	O
crossover	B-Protocol
cable	I-Protocol
was	O
needed	O
to	O
interconnect	O
similar	O
network	B-Device
equipment	I-Device
(	O
such	O
as	O
Ethernet	B-Protocol
hubs	I-Protocol
to	O
Ethernet	B-Protocol
hubs	I-Protocol
)	O
.	O
</s>
<s>
Crossover	B-Protocol
cables	I-Protocol
are	O
sometimes	O
still	O
used	O
to	O
connect	O
two	O
computers	O
together	O
without	O
a	O
switch	O
or	O
hub	B-Protocol
,	O
however	O
most	O
network	O
interface	O
cards	O
(	O
NIC	O
)	O
in	O
use	O
today	O
implement	O
auto	O
MDI-X	O
to	O
automatically	O
configure	O
themselves	O
based	O
on	O
the	O
type	O
of	O
cable	O
plugged	O
into	O
them	O
.	O
</s>
<s>
Two	O
types	O
of	O
8P8C	O
plugs	B-Protocol
and	O
crimping	O
tools	O
for	O
installing	O
the	O
plug	O
onto	O
a	O
cable	O
are	O
commonly	O
available	O
:	O
Western	O
Electric/Stewart	O
Stamping	O
(	O
WE/SS	O
)	O
and	O
Tyco/AMP	O
.	O
</s>
<s>
WE/SS	O
compatible	O
plugs	B-Protocol
are	O
available	O
from	O
a	O
large	O
number	O
of	O
manufacturers	O
,	O
whereas	O
Tyco/AMP	O
plugs	B-Protocol
are	O
produced	O
exclusively	O
by	O
Tyco	O
Electronics	O
.	O
</s>
<s>
Both	O
types	O
of	O
modular	B-Architecture
plugs	I-Architecture
can	O
be	O
mated	O
with	O
a	O
standard	O
8P8C	O
modular	B-Architecture
jack	I-Architecture
.	O
</s>
<s>
Both	O
types	O
of	O
8P8C	O
plugs	B-Protocol
are	O
available	O
in	O
shielded	O
and	O
unshielded	O
varieties	O
for	O
different	O
attenuation	O
tolerances	O
as	O
needed	O
.	O
</s>
<s>
Shielded	O
plugs	B-Protocol
are	O
more	O
expensive	O
and	O
require	O
shielded	O
cable	O
,	O
but	O
have	O
a	O
lower	O
attenuation	O
,	O
and	O
may	O
reduce	O
electromagnetic	O
interference	O
.	O
</s>
<s>
8P8C	O
connectors	O
are	O
commonly	O
used	O
in	O
computer	B-Architecture
networking	I-Architecture
applications	O
,	O
where	O
interconnecting	O
cables	O
are	O
terminated	O
at	O
each	O
end	O
with	O
an	O
8P8C	O
modular	B-Architecture
plug	I-Architecture
wired	O
according	O
to	O
TIA/EIA	O
standards	O
.	O
</s>
<s>
Most	O
wired	B-Protocol
Ethernet	I-Protocol
communications	O
are	O
carried	O
over	O
Category	B-Protocol
5e	I-Protocol
or	O
Category	O
6	O
cable	O
terminated	O
with	O
8P8C	O
modular	B-Architecture
plugs	I-Architecture
.	O
</s>
<s>
While	O
this	O
allows	O
an	O
RJ11	O
plug	O
to	O
connect	O
,	O
it	O
may	O
damage	O
the	O
modular	B-Architecture
jack	I-Architecture
;	O
an	O
approved	O
converter	O
prevents	O
damage	O
.	O
</s>
<s>
This	O
application	O
is	O
common	O
as	O
a	O
console	O
interface	O
for	O
network	B-Device
equipment	I-Device
,	O
such	O
as	O
switches	B-Protocol
,	O
routers	B-Protocol
,	O
and	O
headless	B-Application
computers	I-Application
.	O
</s>
<s>
8P8C	O
modular	B-Architecture
connectors	I-Architecture
are	O
also	O
commonly	O
used	O
as	O
a	O
microphone	O
connector	O
for	O
PMR	O
,	O
LMR	O
,	O
and	O
amateur	O
radio	O
transceivers	O
.	O
</s>
<s>
Frequently	O
the	O
pinout	B-Application
is	O
different	O
,	O
usually	O
mirrored	O
(	O
i.e.	O
</s>
<s>
The	O
physical	O
connector	O
is	O
standardized	O
as	O
the	O
IEC	O
60603-7	O
8P8C	O
modular	B-Architecture
connector	I-Architecture
with	O
different	O
categories	O
of	O
performance	O
.	O
</s>
<s>
The	O
physical	O
dimensions	O
of	O
the	O
male	O
and	O
female	O
connectors	O
are	O
specified	O
in	O
ANSI/TIA	O
-1096-A	O
and	O
ISO-8877	O
standards	O
and	O
normally	O
wired	O
to	O
the	O
T568A	O
and	O
T568B	O
pinouts	B-Application
specified	O
in	O
the	O
ANSI/TIA	O
-568	O
standard	O
to	O
be	O
compatible	O
with	O
both	O
telephone	O
and	O
Ethernet	O
.	O
</s>
<s>
The	O
original	O
RJ45S	O
keyed	O
8P2C	O
modular	B-Architecture
connector	I-Architecture
,	O
obsolete	O
today	O
,	O
had	O
pins	O
5	O
and	O
4	O
wired	O
for	O
tip	O
and	O
ring	O
of	O
a	O
single	O
telephone	O
line	O
and	O
pins	O
7	O
and	O
8	O
shorting	O
a	O
programming	O
resistor	O
.	O
</s>
<s>
Electronics	O
catalogs	O
commonly	O
advertise	O
8P8C	O
modular	B-Architecture
connectors	I-Architecture
as	O
RJ45	O
.	O
</s>
<s>
A	O
router	B-Protocol
to	O
router	B-Protocol
crossover	B-Protocol
cable	I-Protocol
uses	O
two	O
8-position	O
connectors	O
and	O
a	O
unshielded	O
twisted	O
pair	O
(	O
UTP	O
)	O
cable	O
with	O
differently	O
wired	O
connectors	O
at	O
each	O
end	O
.	O
</s>
<s>
The	O
10P10C	O
connector	O
is	O
commonly	O
referred	O
to	O
as	O
an	O
RJ50	O
connector	O
,	O
although	O
this	O
was	O
never	O
a	O
standard	O
registered	B-Protocol
jack	I-Protocol
.	O
</s>
<s>
The	O
10P10C	O
has	O
10	O
contact	B-Protocol
positions	O
and	O
10	O
contacts	O
.	O
</s>
<s>
The	O
most	O
common	O
uses	O
of	O
the	O
10P10C	O
connector	O
are	O
in	O
proprietary	O
data	O
transfer	O
systems	O
,	O
such	O
as	O
the	O
Digiboard	B-Application
and	O
Equinox	O
Super-Serial	O
multi-port	O
TIA-232	O
adapters	O
.	O
</s>
<s>
This	O
connector	O
is	O
also	O
used	O
by	O
some	O
vendors	O
,	O
for	O
example	O
,	O
Cyclades	O
(	O
later	O
absorbed	O
by	O
Equinox	O
)	O
used	O
pin	B-Protocol
1	I-Protocol
as	O
an	O
RI	O
(	O
ring	O
indicator	O
)	O
signal	O
,	O
which	O
is	O
seldom	O
used	O
,	O
allowing	O
an	O
8P8C	O
plug	O
to	O
be	O
inserted	O
to	O
their	O
10P10C	O
socket	O
for	O
most	O
applications	O
.	O
</s>
<s>
US	O
government	O
documents	O
define	O
registered	B-Protocol
jack	I-Protocol
applications	O
of	O
modular	B-Architecture
connectors	I-Architecture
for	O
telecommunications	O
.	O
</s>
