<s>
Packet	B-Protocol
injection	I-Protocol
(	O
also	O
known	O
as	O
forging	O
packets	B-Protocol
or	O
spoofing	O
packets	B-Protocol
)	O
in	O
computer	B-Architecture
networking	I-Architecture
,	O
is	O
the	O
process	O
of	O
interfering	O
with	O
an	O
established	O
network	B-Architecture
connection	I-Architecture
by	O
means	O
of	O
constructing	O
packets	B-Protocol
to	O
appear	O
as	O
if	O
they	O
are	O
part	O
of	O
the	O
normal	O
communication	O
stream	O
.	O
</s>
<s>
The	O
packet	B-Protocol
injection	I-Protocol
process	O
allows	O
an	O
unknown	O
third	O
party	O
to	O
disrupt	O
or	O
intercept	O
packets	B-Protocol
from	O
the	O
consenting	O
parties	O
that	O
are	O
communicating	O
,	O
which	O
can	O
lead	O
to	O
degradation	O
or	O
blockage	O
of	O
users	O
 '	O
ability	O
to	O
utilize	O
certain	O
network	B-General_Concept
services	I-General_Concept
or	O
protocols	O
.	O
</s>
<s>
Packet	B-Protocol
injection	I-Protocol
is	O
commonly	O
used	O
in	O
man-in-the-middle	O
attacks	O
and	O
denial-of-service	O
attacks	O
.	O
</s>
<s>
By	O
utilizing	O
raw	B-Protocol
sockets	I-Protocol
,	O
NDIS	B-Application
function	O
calls	O
,	O
or	O
direct	O
access	O
to	O
a	O
network	B-Protocol
adapter	I-Protocol
kernel	B-Application
mode	I-Application
driver	I-Application
,	O
arbitrary	O
packets	B-Protocol
can	O
be	O
constructed	O
and	O
injected	O
into	O
a	O
computer	B-Architecture
network	I-Architecture
.	O
</s>
<s>
These	O
arbitrary	O
packets	B-Protocol
can	O
be	O
constructed	O
from	O
any	O
type	O
of	O
packet	B-Protocol
protocol	O
(	O
ICMP	B-Protocol
,	O
TCP	B-Protocol
,	O
UDP	B-Protocol
,	O
and	O
others	O
)	O
since	O
there	O
is	O
full	O
control	O
over	O
the	O
packet	B-General_Concept
header	I-General_Concept
while	O
the	O
packet	B-Protocol
is	O
being	O
assembled	O
.	O
</s>
<s>
Packet	B-Protocol
injection	I-Protocol
has	O
been	O
used	O
for	O
:	O
</s>
<s>
Through	O
the	O
process	O
of	O
running	O
a	O
packet	B-Protocol
analyzer	I-Protocol
or	O
packet	B-Protocol
sniffer	I-Protocol
on	O
both	O
network	B-Protocol
service	I-Protocol
access	I-Protocol
points	I-Protocol
trying	O
to	O
establish	O
communication	O
,	O
the	O
results	O
can	O
be	O
compared	O
.	O
</s>
<s>
If	O
point	O
A	O
has	O
no	O
record	O
of	O
sending	O
certain	O
packets	B-Protocol
that	O
show	O
up	O
in	O
the	O
log	O
at	O
point	O
B	O
,	O
and	O
vice	O
versa	O
,	O
then	O
the	O
packet	B-Protocol
log	O
inconsistencies	O
show	O
that	O
those	O
packets	B-Protocol
have	O
been	O
forged	O
and	O
injected	O
by	O
an	O
intermediary	O
access	B-Protocol
point	I-Protocol
.	O
</s>
<s>
Usually	O
TCP	B-Protocol
resets	O
are	O
sent	O
to	O
both	O
access	B-Protocol
points	I-Protocol
to	O
disrupt	O
communication	O
.	O
</s>
