<s>
In	O
computer	B-Architecture
networking	I-Architecture
,	O
promiscuous	B-Protocol
mode	I-Protocol
is	O
a	O
mode	O
for	O
a	O
wired	O
network	B-Protocol
interface	I-Protocol
controller	I-Protocol
(	O
NIC	O
)	O
or	O
wireless	B-General_Concept
network	I-General_Concept
interface	I-General_Concept
controller	I-General_Concept
(	O
WNIC	O
)	O
that	O
causes	O
the	O
controller	O
to	O
pass	O
all	O
traffic	O
it	O
receives	O
to	O
the	O
central	B-General_Concept
processing	I-General_Concept
unit	I-General_Concept
(	O
CPU	O
)	O
rather	O
than	O
passing	O
only	O
the	O
frames	O
that	O
the	O
controller	O
is	O
specifically	O
programmed	O
to	O
receive	O
.	O
</s>
<s>
This	O
mode	O
is	O
normally	O
used	O
for	O
packet	B-Protocol
sniffing	I-Protocol
that	O
takes	O
place	O
on	O
a	O
router	B-Protocol
or	O
on	O
a	O
computer	O
connected	O
to	O
a	O
wired	O
network	O
or	O
one	O
being	O
part	O
of	O
a	O
wireless	B-Architecture
LAN	I-Architecture
.	O
</s>
<s>
Interfaces	O
are	O
placed	O
into	O
promiscuous	B-Protocol
mode	I-Protocol
by	O
software	B-Protocol
bridges	I-Protocol
often	O
used	O
with	O
hardware	B-General_Concept
virtualization	I-General_Concept
.	O
</s>
<s>
In	O
non-promiscuous	O
mode	O
,	O
when	O
a	O
NIC	O
receives	O
a	O
frame	O
,	O
it	O
drops	O
it	O
unless	O
the	O
frame	O
is	O
addressed	O
to	O
that	O
NIC	O
's	O
MAC	O
address	O
or	O
is	O
a	O
broadcast	B-Operating_System
or	O
multicast	O
addressed	O
frame	O
.	O
</s>
<s>
In	O
promiscuous	B-Protocol
mode	I-Protocol
,	O
however	O
,	O
the	O
NIC	O
allows	O
all	O
frames	O
through	O
,	O
thus	O
allowing	O
the	O
computer	O
to	O
read	O
frames	O
intended	O
for	O
other	O
machines	O
or	O
network	O
devices	O
.	O
</s>
<s>
Many	O
operating	B-General_Concept
systems	I-General_Concept
require	O
superuser	B-Application
privileges	O
to	O
enable	O
promiscuous	B-Protocol
mode	I-Protocol
.	O
</s>
<s>
A	O
non-routing	O
node	B-Protocol
in	O
promiscuous	B-Protocol
mode	I-Protocol
can	O
generally	O
only	O
monitor	O
traffic	O
to	O
and	O
from	O
other	O
nodes	O
within	O
the	O
same	O
broadcast	B-Architecture
domain	I-Architecture
(	O
for	O
Ethernet	O
and	O
IEEE	O
802.11	O
)	O
or	O
ring	O
(	O
for	O
Token	B-Device
Ring	I-Device
)	O
.	O
</s>
<s>
Computers	O
attached	O
to	O
the	O
same	O
Ethernet	B-Protocol
hub	I-Protocol
satisfy	O
this	O
requirement	O
,	O
which	O
is	O
why	O
network	B-Protocol
switches	I-Protocol
are	O
used	O
to	O
combat	O
malicious	O
use	O
of	O
promiscuous	B-Protocol
mode	I-Protocol
.	O
</s>
<s>
A	O
router	B-Protocol
may	O
monitor	O
all	O
traffic	O
that	O
it	O
routes	O
.	O
</s>
<s>
Promiscuous	B-Protocol
mode	I-Protocol
is	O
often	O
used	O
to	O
diagnose	O
network	O
connectivity	O
issues	O
.	O
</s>
<s>
Some	O
protocols	O
like	O
FTP	B-Protocol
and	O
Telnet	B-Protocol
transfer	O
data	O
and	O
passwords	O
in	O
clear	O
text	O
,	O
without	O
encryption	O
,	O
and	O
network	O
scanners	O
can	O
see	O
this	O
data	O
.	O
</s>
<s>
Therefore	O
,	O
computer	O
users	O
are	O
encouraged	O
to	O
stay	O
away	O
from	O
insecure	O
protocols	O
like	O
telnet	B-Protocol
and	O
use	O
more	O
secure	O
ones	O
such	O
as	O
SSH	B-Protocol
.	O
</s>
<s>
As	O
promiscuous	B-Protocol
mode	I-Protocol
can	O
be	O
used	O
in	O
a	O
malicious	O
way	O
to	O
capture	O
private	O
data	B-General_Concept
in	I-General_Concept
transit	I-General_Concept
on	O
a	O
network	O
,	O
computer	O
security	O
professionals	O
might	O
be	O
interested	O
in	O
detecting	O
network	O
devices	O
that	O
are	O
in	O
promiscuous	B-Protocol
mode	I-Protocol
.	O
</s>
<s>
In	O
promiscuous	B-Protocol
mode	I-Protocol
,	O
some	O
software	O
might	O
send	O
responses	O
to	O
frames	O
even	O
though	O
they	O
were	O
addressed	O
to	O
another	O
machine	O
.	O
</s>
<s>
If	O
the	O
adapter	O
is	O
in	O
promiscuous	B-Protocol
mode	I-Protocol
,	O
the	O
frame	O
will	O
be	O
passed	O
on	O
,	O
and	O
the	O
IP	O
stack	O
on	O
the	O
machine	O
(	O
to	O
which	O
a	O
MAC	O
address	O
has	O
no	O
meaning	O
)	O
will	O
respond	O
as	O
it	O
would	O
to	O
any	O
other	O
ping	O
.	O
</s>
<s>
The	O
following	O
applications	O
and	O
applications	O
classes	O
use	O
promiscuous	B-Protocol
mode	I-Protocol
.	O
</s>
