<s>
A	O
virtual	B-General_Concept
network	I-General_Concept
interface	I-General_Concept
(	O
VIF	O
)	O
is	O
an	O
abstract	O
virtualized	O
representation	O
of	O
a	O
computer	O
network	O
interface	O
that	O
may	O
or	O
may	O
not	O
correspond	O
directly	O
to	O
a	O
network	B-Protocol
interface	I-Protocol
controller	I-Protocol
.	O
</s>
<s>
It	O
is	O
common	O
for	O
the	O
operating	B-Operating_System
system	I-Operating_System
kernel	I-Operating_System
to	O
maintain	O
a	O
table	O
of	O
virtual	B-General_Concept
network	I-General_Concept
interfaces	I-General_Concept
in	O
memory	O
.	O
</s>
<s>
entitled	O
TCP/IP	O
Illustrated	O
,	O
refers	O
to	O
the	O
kernel	B-Operating_System
's	O
Virtual	B-General_Concept
Interface	I-General_Concept
Table	O
in	O
his	O
discussion	O
of	O
multicast	O
routing	O
.	O
</s>
<s>
bypass	O
the	O
kernel	B-Operating_System
for	O
optimization	O
purposes	O
.	O
</s>
