<s>
Internet	B-Protocol
Connection	I-Protocol
Sharing	I-Protocol
(	O
ICS	O
)	O
is	O
a	O
Windows	O
service	O
that	O
enables	O
one	O
Internet-connected	O
computer	O
to	O
share	O
its	O
Internet	O
connection	O
with	O
other	O
computers	O
on	O
a	O
local	B-General_Concept
area	I-General_Concept
network	I-General_Concept
(	O
LAN	B-General_Concept
)	O
.	O
</s>
<s>
The	O
computer	O
that	O
shares	O
its	O
Internet	O
connection	O
serves	O
as	O
a	O
gateway	B-Application
device	I-Application
,	O
meaning	O
that	O
all	O
traffic	O
between	O
other	O
computers	O
and	O
the	O
Internet	O
go	O
through	O
this	O
computer	O
.	O
</s>
<s>
ICS	O
provides	O
Dynamic	B-Protocol
Host	I-Protocol
Configuration	I-Protocol
Protocol	I-Protocol
(	O
DHCP	B-Protocol
)	O
and	O
network	B-Protocol
address	I-Protocol
translation	I-Protocol
(	O
NAT	O
)	O
services	O
for	O
the	O
LAN	B-General_Concept
computers	O
.	O
</s>
<s>
ICS	O
routes	O
TCP/IP	B-Protocol
packets	O
from	O
a	O
small	O
LAN	B-General_Concept
to	O
the	O
Internet	O
.	O
</s>
<s>
ICS	O
provides	O
NAT	O
services	O
,	O
mapping	O
individual	O
IP	B-Protocol
addresses	I-Protocol
of	O
local	O
computers	O
to	O
unused	O
port	B-Protocol
numbers	I-Protocol
in	O
the	O
sharing	O
computer	O
.	O
</s>
<s>
Because	O
of	O
the	O
nature	O
of	O
the	O
NAT	O
,	O
IP	B-Protocol
addresses	I-Protocol
on	O
the	O
local	O
computer	O
are	O
not	O
visible	O
on	O
the	O
Internet	O
.	O
</s>
<s>
All	O
packets	O
leaving	O
or	O
entering	O
the	O
LAN	B-General_Concept
are	O
sent	O
from	O
or	O
to	O
the	O
IP	B-Protocol
address	I-Protocol
of	O
the	O
external	O
adapter	O
on	O
the	O
ICS	O
host	O
computer	O
.	O
</s>
<s>
Typically	O
,	O
ICS	O
can	O
be	O
used	O
when	O
there	O
are	O
several	O
network	B-Protocol
interface	I-Protocol
cards	I-Protocol
installed	O
on	O
the	O
host	O
computer	O
.	O
</s>
<s>
ICS	O
can	O
also	O
share	O
dial-up	O
(	O
including	O
PSTN	O
,	O
ISDN	B-Protocol
and	O
ADSL	O
connections	O
)	O
,	O
PPPoE	B-Protocol
and	O
VPN	B-Application
connections	O
.	O
</s>
<s>
Starting	O
with	O
Windows	O
XP	O
,	O
ICS	O
is	O
integrated	O
with	O
UPnP	B-Application
,	O
allowing	O
remote	O
discovery	O
and	O
control	O
of	O
the	O
ICS	O
host	O
.	O
</s>
<s>
When	O
connected	O
to	O
a	O
Windows	B-General_Concept
domain	I-General_Concept
,	O
the	O
computer	O
can	O
have	O
a	O
Group	O
Policy	O
to	O
restrict	O
the	O
use	O
of	O
ICS	O
,	O
but	O
when	O
at	O
home	O
,	O
ICS	O
can	O
be	O
enabled	O
.	O
</s>
<s>
ICS	O
was	O
initially	O
designed	O
to	O
connect	O
only	O
to	O
Windows	B-Application
computers	I-Application
:	O
computers	O
on	O
other	O
operating	O
systems	O
required	O
different	O
steps	O
to	O
utilize	O
ICS	O
.	O
</s>
<s>
On	O
Windows	O
XP	O
,	O
the	O
server	O
,	O
by	O
default	O
,	O
gets	O
the	O
IP	B-Protocol
address	I-Protocol
192.168.0.1	O
.	O
</s>
<s>
(	O
This	O
default	O
can	O
be	O
changed	O
within	O
the	O
interface	O
settings	O
of	O
the	O
network	B-Protocol
adapter	I-Protocol
or	O
in	O
the	O
Windows	B-Protocol
Registry	I-Protocol
.	O
)	O
</s>
<s>
It	O
provides	O
NAT	O
services	O
to	O
the	O
entire	O
192.168.0.x	O
subnet	O
,	O
even	O
if	O
the	O
address	O
on	O
the	O
client	O
was	O
set	O
manually	O
,	O
not	O
by	O
the	O
DHCP	B-Protocol
server	I-Protocol
.	O
</s>
<s>
Since	O
Windows	B-Device
7	I-Device
,	O
the	O
192.168.137.x	O
subnet	O
has	O
been	O
used	O
by	O
default	O
.	O
</s>
<s>
Alternatives	O
to	O
ICS	O
include	O
hardware	O
home	O
routers	B-Protocol
and	O
Wireless	B-Device
access	I-Device
points	I-Device
with	O
integrated	O
Internet	O
access	O
hardware	O
,	O
such	O
as	O
broadband	O
over	O
power	O
lines	O
,	O
WiMAX	O
or	O
DSL	B-Device
modems	I-Device
.	O
</s>
