<s>
LocalTalk	B-Device
is	O
a	O
particular	O
implementation	O
of	O
the	O
physical	B-Application
layer	I-Application
of	O
the	O
AppleTalk	B-Application
networking	B-Protocol
system	O
from	O
Apple	O
Computer	O
.	O
</s>
<s>
LocalTalk	B-Device
specifies	O
a	O
system	O
of	O
shielded	O
twisted	O
pair	O
cabling	O
,	O
plugged	O
into	O
self-terminating	O
transceivers	O
,	O
running	O
at	O
a	O
rate	O
of	O
230.4	O
kbit/s	O
.	O
</s>
<s>
Networking	B-Protocol
was	O
envisioned	O
in	O
the	O
Macintosh	B-Device
during	O
planning	O
,	O
so	O
the	O
Mac	O
was	O
given	O
expensive	O
RS-422	O
capable	O
serial	B-Protocol
ports	I-Protocol
,	O
first	O
on	O
a	O
nine-pin	B-Protocol
D-connector	I-Protocol
,	O
then	O
on	O
a	O
Mini-DIN-8	B-Protocol
connector	O
.	O
</s>
<s>
The	O
ports	O
were	O
driven	O
by	O
the	O
Zilog	B-Device
SCC	I-Device
,	O
which	O
could	O
serve	O
as	O
either	O
a	O
standard	O
UART	O
or	O
handle	O
the	O
much	O
more	O
complicated	O
HDLC	O
protocol	O
,	O
which	O
was	O
a	O
packet	O
oriented	O
protocol	O
that	O
incorporated	O
addressing	O
,	O
bit-stuffing	O
,	O
and	O
packet	O
checksumming	O
in	O
hardware	O
.	O
</s>
<s>
When	O
the	O
SCC	O
's	O
internal	O
PLL	O
was	O
used	O
to	O
lock	O
to	O
the	O
clock	O
embedded	O
in	O
the	O
LocalTalk	B-Device
serial	O
data	O
stream	O
(	O
using	O
its	O
FM0	O
encoding	O
method	O
)	O
a	O
divide-by-16	O
setting	O
on	O
the	O
PLL	O
yielded	O
the	O
fastest	O
rate	O
available	O
,	O
namely	O
230.4	O
kbit/s	O
.	O
</s>
<s>
Originally	O
released	O
as	O
"	O
AppleTalk	B-Application
Personal	O
Network	O
,	O
"	O
LocalTalk	B-Device
used	O
shielded	O
twisted-pair	O
cable	O
with	O
3-pin	O
Mini-DIN	B-Protocol
connectors	I-Protocol
.	O
</s>
<s>
Cables	O
were	O
daisy-chained	B-Application
from	O
transceiver	O
to	O
transceiver	O
.	O
</s>
<s>
Each	O
transceiver	O
had	O
two	O
3-pin	O
Mini-DIN	B-Protocol
ports	O
,	O
and	O
a	O
"	O
pigtail	O
"	O
cable	O
to	O
connect	O
to	O
the	O
Mac	O
's	O
DE-9	B-Protocol
serial	B-Protocol
connector	I-Protocol
.	O
</s>
<s>
Later	O
,	O
when	O
the	O
Mac	O
Plus	O
introduced	O
the	O
8-pin	O
Mini-DIN	B-Protocol
serial	B-Protocol
connector	I-Protocol
,	O
transceivers	O
were	O
updated	O
as	O
well	O
.	O
</s>
<s>
A	O
variation	O
of	O
LocalTalk	B-Device
called	O
PhoneNet	B-Protocol
was	O
introduced	O
by	O
Farallon	O
Computing	O
.	O
</s>
<s>
It	O
used	O
standard	O
unshielded	O
side-by-side	O
telephone	O
wire	O
,	O
with	O
six-position	O
modular	B-Architecture
connectors	I-Architecture
(	O
same	O
as	O
the	O
popular	O
RJ11	O
telephone	O
connectors	O
)	O
connected	O
to	O
a	O
PhoneNet	B-Protocol
transceiver	O
,	O
instead	O
of	O
the	O
expensive	O
,	O
shielded	O
,	O
twisted-pair	O
cable	O
.	O
</s>
<s>
In	O
addition	O
to	O
being	O
lower	O
cost	O
,	O
PhoneNet-wired	O
networks	O
were	O
more	O
reliable	O
due	O
to	O
the	O
connections	O
being	O
more	O
difficult	O
to	O
accidentally	O
disconnect	O
.	O
</s>
<s>
In	O
addition	O
,	O
because	O
it	O
used	O
the	O
"	O
outer	O
"	O
pair	O
of	O
the	O
modular	B-Architecture
connector	I-Architecture
,	O
it	O
could	O
travel	O
on	O
many	O
pre-existing	O
phone	O
cables	O
and	O
jacks	O
where	O
just	O
the	O
inner	O
pair	O
was	O
in	O
use	O
for	O
RJ11	O
telephone	O
service	O
.	O
</s>
<s>
PhoneNet	B-Protocol
was	O
also	O
able	O
to	O
use	O
an	O
office	O
's	O
existing	O
phone	O
wire	O
,	O
allowing	O
for	O
entire	O
floors	O
of	O
computers	O
to	O
be	O
easily	O
networked	O
.	O
</s>
<s>
These	O
factors	O
led	O
to	O
PhoneNet	B-Protocol
largely	O
supplanting	O
LocalTalk	B-Device
wiring	O
in	O
low-cost	O
networking	B-Protocol
.	O
</s>
<s>
The	O
useful	O
life	O
of	O
PhoneNet	B-Protocol
was	O
extended	O
with	O
the	O
introduction	O
of	O
LocalTalk	B-Device
switching	O
technology	O
by	O
Tribe	O
Computer	O
Works	O
.	O
</s>
<s>
Introduced	O
in	O
1990	O
,	O
the	O
Tribe	O
LocalSwitch	O
was	O
a	O
16-port	O
packet	O
switch	O
designed	O
to	O
speed	O
up	O
overloaded	O
PhoneNet	B-Protocol
networks	O
.	O
</s>
<s>
The	O
widespread	O
availability	O
of	O
Ethernet-based	O
networking	B-Protocol
in	O
the	O
early	O
1990s	O
led	O
to	O
the	O
swift	O
disappearance	O
of	O
both	O
LocalTalk	B-Device
and	O
PhoneNet	B-Protocol
.	O
</s>
<s>
Early	O
models	O
of	O
Power	B-Device
Macintosh	I-Device
and	O
the	O
Macintosh	B-Device
Quadra	I-Device
supported	O
10BASE-T	O
via	O
the	O
Apple	B-Protocol
Attachment	I-Protocol
Unit	I-Protocol
Interface	I-Protocol
while	O
still	O
supporting	O
LocalTalk-based	O
networking	B-Protocol
.	O
</s>
<s>
For	O
older	O
Macintosh	B-Device
computers	O
that	O
did	O
not	O
have	O
built-in	O
Ethernet	O
expansion	O
options	O
,	O
a	O
high	O
speed	O
SCSI-to-Ethernet	O
adapter	O
was	O
available	O
,	O
and	O
was	O
particularly	O
popular	O
on	O
PowerBooks	B-Device
.	O
</s>
<s>
This	O
enabled	O
all	O
but	O
the	O
earliest	O
Macintosh	B-Device
models	O
to	O
access	O
a	O
high	O
speed	O
Ethernet	O
network	O
.	O
</s>
<s>
With	O
the	O
release	O
of	O
the	O
iMac	B-Device
in	O
1998	O
the	O
traditional	O
Mac	O
serial	O
portand	O
thus	O
,	O
the	O
ability	O
to	O
use	O
both	O
LocalTalk	B-Device
and	O
PhoneNetdisappeared	O
from	O
new	O
models	O
of	O
Macintosh	B-Device
.	O
</s>
<s>
LocalTalk-to-Ethernet	O
bridges	O
were	O
introduced	O
to	O
allow	O
legacy	B-Device
devices	I-Device
(	O
especially	O
printers	O
)	O
to	O
function	O
on	O
newer	O
networks	O
.	O
</s>
<s>
For	O
very	O
old	O
Macintosh	B-Device
computers	O
,	O
LocalTalk	B-Device
remains	O
the	O
only	O
option	O
.	O
</s>
<s>
The	O
LocalTalk	B-Device
connector	O
had	O
the	O
distinction	O
of	O
being	O
the	O
first	O
to	O
use	O
Apple	O
's	O
unified	O
AppleTalk	B-Application
Connector	O
Family	O
design	O
,	O
created	O
by	O
Brad	O
Bissell	O
of	O
Frog	O
Design	O
using	O
Rick	O
Meadows	O
 '	O
Apple	O
Icon	O
Family	O
designs	O
.	O
</s>
<s>
LocalTalk	B-Device
connectors	O
were	O
first	O
released	O
in	O
January	O
1985	O
to	O
connect	O
the	O
LaserWriter	O
printer	O
initially	O
with	O
the	O
Macintosh	B-Device
family	O
of	O
computers	O
as	O
an	O
integral	O
part	O
of	O
the	O
newly	O
announced	O
Macintosh	B-Device
Office	I-Device
.	O
</s>
