How to
configure your Alcatel SpeedTouch 510
ADSL modem not to use NAT?
This
document describes how you can configure
an Alcatel SpeedTouch 510 ADSL modem not
to use NAT anymore. This process is
often called DHCP SPOOFING. The public
IP will be sent to your machine by DHCP
therefore eliminating NAT. It is also
for setups where combination of an
Ethernet gateway routers which do not
have PPTP dialer support are in placed.
Doing so will enable you to configure an
internal router or a server that has
routing software installed and have it
receive an IP address from your ISP -
instead of having the dialer obtain the
address for you.
The
difference between DHCP SPOOFING and
BRIDGING (described here Configure
Alcatel SpeedTouch Pro to Act as a
Transparent Bridge) is that with
bridging the end-machine/router does the
dialing, and so it gets the real IP
address from the ISP. With spoofing the
modem dials for you, receives the IP
address from the ISP, and then gives it
to the end-machine/router.
This
method will work if one of the following
assumptions is true:
-
Your modem is connected to the
Internet and another computer is
connected to your modem.
-
Your modem is connected to the
Internet and you have a router that
is connected to the modem. This
router must have NAT capabilities.
The router will then be connected to
a hub/switch, and to it other
computers will connect.
-
Your modem is connected to the
Internet and you have a server
computer that is connected to the
modem. This server must have Routing
and NAT capabilities. The server
will then be configured with another
NIC, and to it you connect another
computer.
-
Your modem is connected to the
Internet and you have a server
computer that is connected to the
modem. This server must have Routing
and NAT capabilities. The server
will then be configured with another
NIC, to which you will then connect
a hub/switch, and to it other
computers will connect.
Make a
note of the fact that the modem will
stop acting as a router with NAT/PAT
which means that you'll have to connect
it to a router or server that has NAT
capabilities. Without such configuration
you won't be able to connect to the
Internet. |