<s>
Call	B-Protocol
recording	I-Protocol
software	I-Protocol
records	O
telephone	O
conversations	O
over	O
PSTN	O
or	O
VoIP	B-Application
in	O
a	O
digital	O
audio	O
file	O
format	O
.	O
</s>
<s>
Most	O
call	B-Protocol
recording	I-Protocol
software	I-Protocol
applications	O
rely	O
on	O
an	O
analogue	O
signal	O
via	O
either	O
a	O
call	O
recording	O
adapter	O
or	O
a	O
telephony	O
board	O
.	O
</s>
<s>
Sometimes	O
a	O
method	O
is	O
supplied	O
with	O
a	O
digital	O
private	B-Device
branch	I-Device
exchange	I-Device
(	O
PBX	O
)	O
that	O
can	O
process	O
the	O
proprietary	O
signal	O
(	O
usually	O
a	O
conversion	O
box	O
)	O
before	O
being	O
channeled	O
to	O
a	O
computer	O
for	O
recording	O
.	O
</s>
<s>
VoIP	B-Protocol
Recording	I-Protocol
is	O
usually	O
restricted	O
to	O
streaming	O
media	O
recorders	O
or	O
software	O
developed	O
by	O
the	O
softphone	B-Protocol
or	O
IP	O
PBX	O
creator	O
.	O
</s>
<s>
There	O
are	O
also	O
solutions	O
which	O
use	O
packet	B-Protocol
capture	I-Protocol
technology	O
to	O
passively	O
record	O
VoIP	B-Application
phone	O
calls	O
on	O
the	O
LAN	B-General_Concept
.	O
</s>
<s>
Some	O
of	O
today	O
's	O
call	B-Protocol
recording	I-Protocol
software	I-Protocol
is	O
sold	O
as	O
a	O
turn-key	O
solution	O
with	O
hardware	O
.	O
</s>
