<s>
Crosstalk	B-Protocol
Mk.4	I-Protocol
was	O
a	O
commercially	O
available	O
PC	O
telecommunications	O
and	O
terminal	B-Application
emulation	I-Application
software	B-Application
package	I-Application
originally	O
produced	O
by	O
Atlanta-based	O
Crosstalk	O
Communications	O
,	O
from	O
the	O
late	O
1980s	O
through	O
1990	O
,	O
and	O
by	O
Digital	O
Communications	O
Associates	O
(	O
DCA	O
)	O
until	O
the	O
mid-1990s	O
.	O
</s>
<s>
Crosstalk	B-Protocol
Mk.4	I-Protocol
was	O
one	O
of	O
a	O
suite	O
of	O
products	O
produced	O
by	O
the	O
company	O
;	O
others	O
included	O
the	O
famed	O
Crosstalk	O
XVI	O
,	O
Crosstalk	O
Communicator	O
,	O
Crosstalk	B-Protocol
for	I-Protocol
Windows	I-Protocol
,	O
and	O
Remote	O
2	O
.	O
</s>
<s>
Its	O
CASL	O
scripting	B-Language
language	I-Language
,	O
though	O
not	O
the	O
program	O
behind	O
it	O
,	O
was	O
still	O
supported	O
(	O
by	O
Micro	O
Focus	O
)	O
in	O
2018	O
.	O
</s>
<s>
Featuring	O
multisession	O
communications	O
capabilities	O
,	O
Crosstalk	B-Protocol
Mk.4	I-Protocol
allowed	O
multiple	O
serial	B-Protocol
ports	I-Protocol
to	O
be	O
used	O
and	O
controlled	O
simultaneously	O
.	O
</s>
<s>
A	O
powerful	O
programming	O
language	O
called	O
CASL	O
(	O
Crosstalk	O
Application	B-Language
Scripting	I-Language
Language	O
)	O
provided	O
full	O
program	O
and	O
communications	O
activity	O
control	O
,	O
and	O
enabled	O
users	O
to	O
create	O
a	O
wide	O
variety	O
of	O
custom	O
applications	O
.	O
</s>
<s>
The	O
company	O
having	O
been	O
acquired	O
and	O
reacquired	O
,	O
as	O
of	O
2018	O
the	O
CASL	O
scripting	B-Language
language	I-Language
is	O
supported	O
by	O
Micro	O
Focus	O
's	O
InfoConnect	O
Desktop	O
offering	O
.	O
</s>
<s>
Digital	O
Communications	O
Associates	O
acquired	O
Microstuf	O
,	O
makers	O
of	O
the	O
Crosstalk	O
Communications	O
package	O
together	O
with	O
their	O
flagship	O
product	O
,	O
the	O
Crosstalk	O
terminal	B-Application
emulation	I-Application
program	O
,	O
in	O
1986	O
.	O
</s>
<s>
It	O
was	O
early	O
1987	O
when	O
DCA	O
won	O
a	O
look	B-Application
and	I-Application
feel	I-Application
lawsuit	O
regarding	O
Crosstalk	O
.	O
</s>
<s>
Crosstalk	B-Protocol
Mk.4	I-Protocol
received	O
many	O
accolades	O
during	O
its	O
production	O
,	O
including	O
PC	O
Magazine	O
Editors	O
 '	O
Choice	O
and	O
PC	O
World	O
Product	O
of	O
the	O
Year	O
awards	O
.	O
</s>
