<s>
X.PC	B-Protocol
is	O
a	O
deprecated	O
communications	O
protocol	O
developed	O
by	O
McDonnell-Douglas	O
for	O
connecting	O
a	O
personal	B-Device
computer	I-Device
to	O
its	O
Tymnet	B-Application
packet-switched	B-Protocol
public	O
data	O
telecommunications	O
network	O
.	O
</s>
<s>
It	O
is	O
a	O
subset	O
of	O
X.25	B-Protocol
,	O
a	O
CCITT	O
standard	O
for	O
packet-switched	B-Protocol
networks	I-Protocol
.	O
</s>
<s>
X.PC	B-Protocol
was	O
originally	O
developed	O
to	O
enable	O
connections	O
up	O
to	O
9600	O
baud	O
.	O
</s>
<s>
Unlike	O
MNP	B-Device
,	O
a	O
competing	O
standard	O
proposed	O
by	O
Microcom	O
,	O
X.PC	B-Protocol
was	O
placed	O
in	O
the	O
public	O
domain	O
for	O
royalty-free	O
usage	O
.	O
</s>
<s>
MNP	B-Device
,	O
on	O
the	O
other	O
hand	O
,	O
initially	O
required	O
a	O
$	O
2,500	O
licensing	O
fee	O
.	O
</s>
<s>
Microcom	O
battled	O
X.PC	B-Protocol
for	O
acceptance	O
in	O
the	O
marketplace	O
,	O
and	O
eventually	O
released	O
MNP	B-Device
1	O
through	O
3	O
into	O
the	O
public	O
domain	O
to	O
compete	O
.	O
</s>
<s>
At	O
the	O
time	O
,	O
several	O
modem	O
manufacturers	O
supported	O
MNP	B-Device
in	O
their	O
products	O
,	O
Microcom	O
and	O
Racal-Vadic	O
being	O
major	O
examples	O
.	O
</s>
<s>
Several	O
companies	O
announced	O
support	O
for	O
X.PC	B-Protocol
,	O
including	O
Hayes	O
,	O
but	O
none	O
of	O
the	O
companies	O
announcing	O
support	O
offered	O
it	O
in	O
their	O
modems	O
.	O
</s>
<s>
X.PC	B-Protocol
quickly	O
disappeared	O
,	O
and	O
Microcom	O
would	O
go	O
on	O
to	O
release	O
MNP	B-Device
4	O
and	O
5	O
into	O
the	O
public	O
domain	O
as	O
well	O
.	O
</s>
