<s>
Network	B-Protocol
forensics	I-Protocol
is	O
a	O
sub-branch	O
of	O
digital	O
forensics	O
relating	O
to	O
the	O
monitoring	O
and	O
analysis	O
of	O
computer	B-Architecture
network	I-Architecture
traffic	O
for	O
the	O
purposes	O
of	O
information	O
gathering	O
,	O
legal	O
evidence	O
,	O
or	O
intrusion	O
detection	O
.	O
</s>
<s>
Network	B-Protocol
traffic	I-Protocol
is	O
transmitted	O
and	O
then	O
lost	O
,	O
so	O
network	B-Protocol
forensics	I-Protocol
is	O
often	O
a	O
pro-active	O
investigation	O
.	O
</s>
<s>
Network	B-Protocol
forensics	I-Protocol
generally	O
has	O
two	O
uses	O
.	O
</s>
<s>
In	O
this	O
case	O
analysis	O
of	O
captured	O
network	B-Protocol
traffic	I-Protocol
can	O
include	O
tasks	O
such	O
as	O
reassembling	O
transferred	O
files	O
,	O
searching	O
for	O
keywords	O
and	O
parsing	O
human	O
communication	O
such	O
as	O
emails	O
or	O
chat	O
sessions	O
.	O
</s>
<s>
Network	B-Protocol
forensics	I-Protocol
is	O
a	O
comparatively	O
new	O
field	O
of	O
forensic	O
science	O
.	O
</s>
<s>
Network	B-Protocol
forensics	I-Protocol
can	O
be	O
performed	O
as	O
a	O
standalone	O
investigation	O
or	O
alongside	O
a	O
computer	O
forensics	O
analysis	O
(	O
where	O
it	O
is	O
often	O
used	O
to	O
reveal	O
links	O
between	O
digital	O
devices	O
or	O
reconstruct	O
how	O
a	O
crime	O
was	O
committed	O
)	O
.	O
</s>
<s>
Marcus	O
Ranum	O
is	O
credited	O
with	O
defining	O
Network	B-Protocol
forensics	I-Protocol
as	O
"	O
the	O
capture	O
,	O
recording	O
,	O
and	O
analysis	O
of	O
network	O
events	O
in	O
order	O
to	O
discover	O
the	O
source	O
of	O
security	O
attacks	O
or	O
other	O
problem	O
incidents	O
"	O
.	O
</s>
<s>
This	O
approach	O
requires	O
a	O
faster	O
processor	B-General_Concept
to	O
keep	O
up	O
with	O
incoming	O
traffic	O
.	O
</s>
<s>
With	O
these	O
tools	O
,	O
website	O
pages	O
,	O
email	O
attachments	O
,	O
and	O
other	O
network	B-Protocol
traffic	I-Protocol
can	O
be	O
reconstructed	O
only	O
if	O
they	O
are	O
transmitted	O
or	O
received	O
unencrypted	O
.	O
</s>
<s>
To	O
collect	O
data	O
on	O
this	O
layer	O
,	O
the	O
network	B-Protocol
interface	I-Protocol
card	I-Protocol
(	O
NIC	O
)	O
of	O
a	O
host	O
can	O
be	O
put	O
into	O
"	O
promiscuous	B-Protocol
mode	I-Protocol
"	O
.	O
</s>
<s>
On	O
the	O
network	O
layer	O
the	O
Internet	B-Protocol
Protocol	I-Protocol
(	O
IP	O
)	O
is	O
responsible	O
for	O
directing	O
the	O
packets	O
generated	O
by	O
TCP	B-Protocol
through	O
the	O
network	O
(	O
e.g.	O
,	O
the	O
Internet	O
)	O
by	O
adding	O
source	O
and	O
destination	O
information	O
which	O
can	O
be	O
interpreted	O
by	O
routers	B-Protocol
all	O
over	O
the	O
network	O
.	O
</s>
<s>
Cellular	O
digital	O
packet	O
networks	O
,	O
like	O
GPRS	B-General_Concept
,	O
use	O
similar	O
protocols	O
like	O
IP	O
,	O
so	O
the	O
methods	O
described	O
for	O
IP	O
work	O
with	O
them	O
as	O
well	O
.	O
</s>
<s>
For	O
the	O
correct	O
routing	O
,	O
every	O
intermediate	O
router	B-Protocol
must	O
have	O
a	O
routing	O
table	O
to	O
know	O
where	O
to	O
send	O
the	O
packet	O
next	O
.	O
</s>
<s>
Given	O
the	O
proliferation	O
of	O
TLS	B-Protocol
encryption	I-Protocol
on	O
the	O
internet	O
,	O
as	O
of	O
April	O
2021	O
it	O
is	O
estimated	O
that	O
half	O
of	O
all	O
malware	O
uses	O
TLS	B-Protocol
to	O
evade	O
detection	O
.	O
</s>
<s>
Encrypted	O
traffic	O
analysis	O
inspects	O
traffic	O
to	O
identify	O
encrypted	O
traffic	O
coming	O
from	O
malware	O
and	O
other	O
threats	O
by	O
detecting	O
suspicious	O
combinations	O
of	O
TLS	B-Protocol
characteristics	O
,	O
usually	O
to	O
uncommon	O
or	O
servers	O
.	O
</s>
<s>
The	O
internet	O
can	O
be	O
a	O
rich	O
source	O
of	O
digital	O
evidence	O
including	O
web	O
browsing	O
,	O
email	O
,	O
newsgroup	B-Application
,	O
synchronous	O
chat	O
and	O
peer-to-peer	O
traffic	O
.	O
</s>
<s>
Email	O
accounts	O
can	O
often	O
contain	O
useful	O
evidence	O
;	O
but	O
email	O
headers	O
are	O
easily	O
faked	O
and	O
,	O
so	O
,	O
network	B-Protocol
forensics	I-Protocol
may	O
be	O
used	O
to	O
prove	O
the	O
exact	O
origin	O
of	O
incriminating	O
material	O
.	O
</s>
<s>
Network	B-Protocol
forensics	I-Protocol
can	O
also	O
be	O
used	O
in	O
order	O
to	O
find	O
out	O
who	O
is	O
using	O
a	O
particular	O
computer	O
by	O
extracting	O
user	O
account	O
information	O
from	O
the	O
network	B-Protocol
traffic	I-Protocol
.	O
</s>
<s>
Wireless	O
forensics	O
is	O
a	O
sub-discipline	O
of	O
network	B-Protocol
forensics	I-Protocol
.	O
</s>
<s>
The	O
main	O
goal	O
of	O
wireless	O
forensics	O
is	O
to	O
provide	O
the	O
methodology	O
and	O
tools	O
required	O
to	O
collect	O
and	O
analyze	O
(	O
wireless	O
)	O
network	B-Protocol
traffic	I-Protocol
that	O
can	O
be	O
presented	O
as	O
valid	O
digital	O
evidence	O
in	O
a	O
court	O
of	O
law	O
.	O
</s>
<s>
The	O
evidence	O
collected	O
can	O
correspond	O
to	O
plain	O
data	O
or	O
,	O
with	O
the	O
broad	O
usage	O
of	O
Voice-over-IP	B-Application
(	O
VoIP	B-Application
)	O
technologies	O
,	O
especially	O
over	O
wireless	O
,	O
can	O
include	O
voice	O
conversations	O
.	O
</s>
<s>
Analysis	O
of	O
wireless	O
network	B-Protocol
traffic	I-Protocol
is	O
similar	O
to	O
that	O
on	O
wired	O
networks	O
,	O
however	O
there	O
may	O
be	O
the	O
added	O
consideration	O
of	O
wireless	B-Application
security	I-Application
measures	O
.	O
</s>
