<s>
PC/TCP	B-Application
Packet	I-Application
Driver	I-Application
is	O
a	O
networking	O
API	B-Application
for	O
MS-DOS	B-Application
,	O
PC	B-Operating_System
DOS	I-Operating_System
,	O
and	O
later	O
x86	B-Operating_System
DOS	B-Operating_System
implementations	O
such	O
as	O
DR-DOS	B-Application
,	O
FreeDOS	B-Application
,	O
etc	O
.	O
</s>
<s>
It	O
implements	O
the	O
lowest	O
levels	O
of	O
a	O
TCP/IP	B-Protocol
stack	I-Protocol
,	O
where	O
the	O
remainder	O
is	O
typically	O
implemented	O
either	O
by	O
terminate-and-stay-resident	O
drivers	O
or	O
as	O
a	O
library	O
linked	O
into	O
an	O
application	O
program	O
.	O
</s>
<s>
A	O
packet	B-Application
driver	I-Application
uses	O
an	O
x86	B-Device
interrupt	I-Device
number	I-Device
(	O
INT	B-Device
)	O
between	O
The	O
number	O
used	O
is	O
detected	O
at	O
runtime	O
,	O
it	O
is	O
most	O
commonly	O
60h	O
but	O
may	O
be	O
changed	O
to	O
avoid	O
application	O
programs	O
which	O
use	O
fixed	O
interrupts	O
for	O
internal	O
communications	O
.	O
</s>
<s>
Packet	B-Application
drivers	I-Application
can	O
implement	O
many	O
different	O
network	O
interfaces	O
,	O
including	O
Ethernet	O
,	O
Token	B-Device
Ring	I-Device
,	O
RS-232	O
,	O
Arcnet	B-Protocol
,	O
and	O
X.25	B-Protocol
.	O
</s>
<s>
WinPKT	O
is	O
a	O
driver	O
that	O
enables	O
use	O
of	O
packet	B-Application
drivers	I-Application
under	O
Microsoft	O
Windows	O
that	O
moves	O
around	O
applications	O
in	O
memory	O
.	O
</s>
<s>
W3C507	O
is	O
a	O
DLL	O
to	O
packet	B-Application
driver	I-Application
for	O
the	O
Microsoft	O
Windows	O
environment	O
.	O
</s>
<s>
Support	O
for	O
Ethernet	O
alike	O
network	O
interface	O
over	O
(	O
using	O
8250	B-Device
UART	I-Device
)	O
,	O
CSLIP	B-Protocol
,	O
,	O
IPX	B-Protocol
,	O
Token	B-Device
Ring	I-Device
,	O
LocalTalk	B-Device
,	O
ARCNET	B-Protocol
.	O
</s>
