<s>
In	O
the	O
field	O
of	O
computer	B-Architecture
network	I-Architecture
administration	O
,	O
pcap	B-Language
is	O
an	O
application	B-Application
programming	I-Application
interface	I-Application
(	O
API	B-Application
)	O
for	O
capturing	B-Protocol
network	I-Protocol
traffic	I-Protocol
.	O
</s>
<s>
While	O
the	O
name	O
is	O
an	O
abbreviation	O
of	O
packet	B-Protocol
capture	I-Protocol
,	O
that	O
is	O
not	O
the	O
API	B-Application
's	O
proper	O
name	O
.	O
</s>
<s>
Unix-like	B-Operating_System
systems	I-Operating_System
implement	O
pcap	B-Language
in	O
the	O
libpcap	B-Language
library	B-Library
;	O
for	O
Windows	B-Application
,	O
there	O
is	O
a	O
port	O
of	O
libpcap	B-Language
named	O
WinPcap	B-Language
that	O
is	O
no	O
longer	O
supported	O
or	O
developed	O
,	O
and	O
a	O
port	O
named	O
Npcap	O
for	O
Windows	B-Device
7	I-Device
and	O
later	O
that	O
is	O
still	O
supported	O
.	O
</s>
<s>
Monitoring	O
software	O
may	O
use	O
libpcap	B-Language
,	O
WinPcap	B-Language
,	O
or	O
Npcap	O
to	O
capture	O
network	B-Protocol
packets	I-Protocol
traveling	O
over	O
a	O
computer	B-Architecture
network	I-Architecture
and	O
,	O
in	O
newer	O
versions	O
,	O
to	O
transmit	O
packets	B-Protocol
on	O
a	O
network	O
at	O
the	O
link	B-Protocol
layer	I-Protocol
,	O
and	O
to	O
get	O
a	O
list	O
of	O
network	O
interfaces	O
for	O
possible	O
use	O
with	O
libpcap	B-Language
,	O
WinPcap	B-Language
,	O
or	O
Npcap	O
.	O
</s>
<s>
The	O
pcap	B-Language
API	B-Application
is	O
written	O
in	O
C	B-Language
,	O
so	O
other	O
languages	O
such	O
as	O
Java	B-Language
,	O
.NET	B-Application
languages	O
,	O
and	O
scripting	B-Language
languages	I-Language
generally	O
use	O
a	O
wrapper	B-Library
;	O
no	O
such	O
wrappers	O
are	O
provided	O
by	O
libpcap	B-Language
or	O
WinPcap	B-Language
itself	O
.	O
</s>
<s>
C++	B-Language
programs	I-Language
may	O
link	O
directly	O
to	O
the	O
C	B-Language
API	B-Application
or	O
use	O
an	O
object-oriented	O
wrapper	B-Library
.	O
</s>
<s>
libpcap	B-Language
,	O
WinPcap	B-Language
,	O
and	O
Npcap	O
provide	O
the	O
packet-capture	O
and	O
filtering	O
engines	O
of	O
many	O
open-source	B-Application
and	O
commercial	O
network	O
tools	O
,	O
including	O
protocol	O
analyzers	O
(	O
packet	B-Protocol
sniffers	I-Protocol
)	O
,	O
network	B-Protocol
monitors	I-Protocol
,	O
network	O
intrusion	O
detection	O
systems	O
,	O
traffic-generators	O
and	O
network-testers	O
.	O
</s>
<s>
libpcap	B-Language
,	O
WinPcap	B-Language
,	O
and	O
Npcap	O
also	O
support	O
saving	O
captured	O
packets	B-Protocol
to	O
a	O
file	O
,	O
and	O
reading	O
files	O
containing	O
saved	O
packets	B-Protocol
;	O
applications	O
can	O
be	O
written	O
,	O
using	O
libpcap	B-Language
,	O
WinPcap	B-Language
,	O
or	O
Npcap	O
,	O
to	O
be	O
able	O
to	O
capture	O
network	O
traffic	O
and	O
analyze	O
it	O
,	O
or	O
to	O
read	O
a	O
saved	O
capture	O
and	O
analyze	O
it	O
,	O
using	O
the	O
same	O
analysis	O
code	O
.	O
</s>
<s>
A	O
capture	O
file	O
saved	O
in	O
the	O
format	O
that	O
libpcap	B-Language
,	O
WinPcap	B-Language
,	O
and	O
Npcap	O
use	O
can	O
be	O
read	O
by	O
applications	O
that	O
understand	O
that	O
format	O
,	O
such	O
as	O
tcpdump	B-Protocol
,	O
Wireshark	B-Language
,	O
CA	O
NetMaster	O
,	O
or	O
Microsoft	B-Protocol
Network	I-Protocol
Monitor	I-Protocol
3.x	I-Protocol
.	O
</s>
<s>
The	O
MIME	B-Application
type	I-Application
for	O
the	O
file	O
format	O
created	O
and	O
read	O
by	O
libpcap	B-Language
,	O
WinPcap	B-Language
,	O
and	O
Npcap	O
is	O
application/vnd.tcpdump.pcap	O
.	O
</s>
<s>
The	O
typical	O
file	O
extension	O
is	O
.pcap	B-Language
,	O
although	O
.cap	O
and	O
.dmp	O
are	O
also	O
in	O
common	O
use	O
.	O
</s>
<s>
libpcap	B-Language
was	O
originally	O
developed	O
by	O
the	O
tcpdump	B-Protocol
developers	O
in	O
the	O
Network	O
Research	O
Group	O
at	O
Lawrence	O
Berkeley	O
Laboratory	O
.	O
</s>
<s>
The	O
low-level	O
packet	B-Protocol
capture	I-Protocol
,	O
capture	O
file	O
reading	O
,	O
and	O
capture	O
file	O
writing	O
code	O
of	O
tcpdump	B-Protocol
was	O
extracted	O
and	O
made	O
into	O
a	O
library	B-Library
,	O
with	O
which	O
tcpdump	B-Protocol
was	O
linked	O
.	O
</s>
<s>
It	O
is	O
now	O
developed	O
by	O
the	O
same	O
tcpdump.org	O
group	O
that	O
develops	O
tcpdump	B-Protocol
.	O
</s>
<s>
While	O
libpcap	B-Language
was	O
originally	O
developed	O
for	O
Unix-like	B-Operating_System
operating	I-Operating_System
systems	I-Operating_System
,	O
a	O
successful	O
port	O
for	O
Windows	B-Application
was	O
made	O
,	O
called	O
WinPcap	B-Language
.	O
</s>
<s>
It	O
has	O
been	O
unmaintained	O
since	O
2013	O
,	O
and	O
several	O
competing	O
forks	B-Application
have	O
been	O
released	O
with	O
new	O
features	O
and	O
support	O
for	O
newer	O
versions	O
of	O
Windows	B-Application
.	O
</s>
<s>
WinPcap	B-Language
consists	O
of	O
:	O
</s>
<s>
x86	B-Operating_System
and	O
x86-64	B-Device
drivers	O
for	O
the	O
Windows	B-Device
NT	I-Device
family	I-Device
(	O
Windows	B-Device
NT	I-Device
4.0	I-Device
,	O
2000	B-Application
,	O
XP	B-Application
,	O
Server	B-Application
2003	I-Application
,	O
Vista	B-Application
,	O
7	B-Device
,	O
8	B-Application
,	O
and	O
10	B-Operating_System
)	O
,	O
which	O
use	O
Network	B-Application
Driver	I-Application
Interface	I-Application
Specification	I-Application
(	O
NDIS	B-Application
)	O
5.x	O
to	O
read	O
packets	B-Protocol
directly	O
from	O
a	O
network	B-Protocol
adapter	I-Protocol
;	O
</s>
<s>
implementations	O
of	O
a	O
lower-level	O
library	B-Library
for	O
the	O
listed	O
operating	O
systems	O
,	O
to	O
communicate	O
with	O
those	O
drivers	O
;	O
</s>
<s>
a	O
port	O
of	O
libpcap	B-Language
that	O
uses	O
the	O
API	B-Application
offered	O
by	O
the	O
low-level	O
library	B-Library
implementations	O
.	O
</s>
<s>
Programmers	O
at	O
the	O
Politecnico	O
di	O
Torino	O
wrote	O
the	O
original	O
code	O
;	O
as	O
of	O
2008	O
CACE	O
Technologies	O
,	O
a	O
company	O
set	O
up	O
by	O
some	O
of	O
the	O
WinPcap	B-Language
developers	O
,	O
developed	O
and	O
maintained	O
the	O
product	O
.	O
</s>
<s>
Because	O
WinPcap	B-Language
uses	O
the	O
older	O
NDIS	B-Application
5.x	O
APIs	B-Application
,	O
it	O
does	O
not	O
work	O
on	O
some	O
builds	O
of	O
Windows	B-Operating_System
10	I-Operating_System
,	O
which	O
have	O
deprecated	O
or	O
removed	O
those	O
APIs	B-Application
in	O
favor	O
of	O
the	O
newer	O
NDIS	B-Application
6.x	O
APIs	B-Application
.	O
</s>
<s>
The	O
WinPcap	B-Language
project	O
has	O
ceased	O
development	O
and	O
WinPcap	B-Language
and	O
WinDump	O
are	O
no	O
longer	O
maintained	O
.	O
</s>
<s>
The	O
last	O
official	O
WinPcap	B-Language
release	O
was	O
4.1.3	O
released	O
March	O
8	B-Application
,	O
2013	O
.	O
</s>
<s>
Npcap	O
is	O
the	O
Nmap	B-Language
Project	O
's	O
packet	B-Protocol
sniffing	I-Protocol
library	B-Library
for	O
Windows	B-Application
.	O
</s>
<s>
It	O
is	O
based	O
on	O
WinPcap	B-Language
,	O
but	O
written	O
to	O
make	O
use	O
of	O
Windows	B-Application
networking	O
improvements	O
in	O
NDIS	B-Application
version	O
6	O
.	O
</s>
<s>
Its	O
authors	O
rewrote	O
the	O
WinPcap	B-Language
NDIS	B-Application
5	O
Protocol	O
Driver	O
as	O
a	O
Light-Weight	O
Filter	O
(	O
LWF	O
)	O
driver	O
,	O
a	O
change	O
that	O
reduces	O
processing	O
overhead	O
.	O
</s>
<s>
Npcap	O
maintenance	O
releases	O
updated	O
the	O
version	O
of	O
the	O
included	O
libpcap	B-Language
library	B-Library
to	O
the	O
latest	O
available	O
,	O
allowing	O
software	O
authors	O
to	O
use	O
the	O
newer	O
API	B-Application
features	O
that	O
Linux	B-Application
software	O
had	O
already	O
supported	O
.	O
</s>
<s>
Most	O
software	O
that	O
used	O
WinPcap	B-Language
can	O
be	O
easily	O
ported	O
to	O
use	O
Npcap	O
with	O
minimal	O
changes	O
.	O
</s>
<s>
Npcap	O
introduced	O
several	O
innovations	O
that	O
were	O
not	O
available	O
in	O
WinPcap	B-Language
:	O
</s>
<s>
Npcap	O
can	O
be	O
restricted	O
so	O
that	O
only	O
Administrators	O
can	O
sniff	O
packets	B-Protocol
.	O
</s>
<s>
Npcap	O
is	O
able	O
to	O
sniff	O
and	O
inject	O
loopback	O
packets	B-Protocol
(	O
transmissions	O
between	O
services	O
on	O
the	O
same	O
machine	O
)	O
by	O
using	O
the	O
Windows	B-Application
Filtering	O
Platform	O
.	O
</s>
<s>
Npcap	O
can	O
capture	O
802.11	O
WiFi	O
frames	O
on	O
a	O
variety	O
of	O
commonly-available	O
network	B-Protocol
adapters	I-Protocol
.	O
</s>
<s>
Win10Pcap	O
implementation	O
is	O
also	O
based	O
on	O
the	O
NDIS	B-Application
6	O
driver	O
model	O
and	O
works	O
stably	O
with	O
Windows	B-Operating_System
10	I-Operating_System
.	O
</s>
<s>
Bit-Twist	B-Protocol
,	O
a	O
libpcap-based	O
Ethernet	O
packet	B-Protocol
generator	O
and	O
editor	O
for	O
BSD	B-Operating_System
,	O
Linux	B-Application
,	O
and	O
Windows	B-Application
.	O
</s>
<s>
EtherApe	B-Language
,	O
a	O
graphical	O
tool	O
for	O
monitoring	O
network	O
traffic	O
and	O
bandwidth	O
usage	O
in	O
real	O
time	O
.	O
</s>
<s>
L0phtCrack	B-Application
,	O
a	O
password	O
auditing	O
and	O
recovery	O
application	O
.	O
</s>
<s>
ngrep	B-Protocol
,	O
aka	O
"	O
network	O
grep	B-Application
"	O
,	O
isolate	O
strings	O
in	O
packets	B-Protocol
,	O
show	O
packet	B-Protocol
data	I-Protocol
in	O
human-friendly	O
output	O
.	O
</s>
<s>
Pirni	B-Protocol
,	O
a	O
discontinued	O
network	O
security	O
tool	O
for	O
jailbroken	B-Application
iOS	B-Operating_System
devices	O
.	O
</s>
<s>
Scapy	B-Protocol
,	O
a	O
packet	B-Protocol
manipulation	O
tool	O
for	O
computer	B-Architecture
networks	I-Architecture
,	O
written	O
in	O
Python	B-Language
by	O
Philippe	O
Biondi	O
.	O
</s>
<s>
Snort	B-Language
,	O
a	O
network-intrusion-detection	O
system	O
.	O
</s>
<s>
Suricata	B-Application
,	O
a	O
network	O
intrusion	O
prevention	O
and	O
analysis	O
platform	O
.	O
</s>
<s>
tcpdump	B-Protocol
,	O
a	O
tool	O
for	O
capturing	O
and	O
dumping	O
packets	B-Protocol
for	O
further	O
analysis	O
,	O
and	O
WinDump	O
,	O
the	O
Windows	B-Application
port	O
of	O
tcpdump	B-Protocol
.	O
</s>
<s>
Zeek	B-Application
,	O
an	O
intrusion	O
detection	O
system	O
and	O
network	O
monitoring	O
platform	O
.	O
</s>
<s>
URL	B-Protocol
Snooper	I-Protocol
,	O
locate	O
the	O
URLs	O
of	O
audio	O
and	O
video	O
files	O
in	O
order	O
to	O
allow	O
recording	O
them	O
.	O
</s>
<s>
WhatPulse	B-Application
,	O
a	O
statistical	O
(	O
input	O
,	O
network	O
,	O
uptime	O
)	O
measuring	O
application	O
.	O
</s>
<s>
Wireshark	B-Language
(	O
formerly	O
Ethereal	B-Language
)	O
,	O
a	O
graphical	O
packet-capture	O
and	O
protocol-analysis	O
tool	O
.	O
</s>
<s>
Xplico	B-Protocol
,	O
a	O
network	O
forensics	O
analysis	O
tool	O
(	O
NFAT	O
)	O
.	O
</s>
<s>
C++	B-Language
:	O
,	O
,	O
</s>
<s>
Perl	B-Language
:	O
</s>
<s>
Python	B-Language
:	O
,	O
,	O
</s>
<s>
Ruby	B-Language
:	O
</s>
<s>
Rust	B-Application
:	O
</s>
<s>
Tcl	B-Operating_System
:	O
,	O
,	O
</s>
<s>
Java	B-Language
:	O
,	O
,	O
,	O
,	O
</s>
<s>
.NET	B-Application
:	O
WinPcapNET	O
,	O
,	O
</s>
<s>
Haskell	B-Language
:	O
</s>
<s>
OCaml	B-Language
:	O
</s>
<s>
Chicken	B-Language
Scheme	I-Language
:	O
</s>
<s>
Common	B-Language
Lisp	I-Language
:	O
</s>
<s>
Racket	B-Operating_System
:	O
</s>
<s>
Erlang	B-Operating_System
:	O
</s>
<s>
Node.js	B-Language
:	O
</s>
<s>
Python	B-Language
:	O
</s>
<s>
Python	B-Language
:	O
</s>
<s>
Apache	B-General_Concept
Drill	I-General_Concept
,	O
an	O
open	O
source	O
SQL	O
engine	O
for	O
interactive	O
analysis	O
of	O
large	O
scale	O
datasets	O
.	O
</s>
<s>
Endace	O
's	O
EndaceProbe	O
,	O
a	O
high	O
scale	O
packet	B-Protocol
capture	I-Protocol
system	O
that	O
continuously	O
records	O
weeks	O
or	O
months	O
of	O
network	O
traffic	O
.	O
</s>
