Mac Forum / General / Hardware / July 2006

 Go under System Preferences.  Click on Network.  Click on Built-in
Ethernet or whatever you have, and click on Configure.  Should be in
there....

Raymond

Some more infomration might be useful: what is the Linksys model, and
what Mac model do you have? (The main question of interest for the Mac
is whether it has Airport or Airport Extreme.)

It sounds like they are talking about the configuration of the router,
not your Mac.

In order to share a DSL or cable connection between multiple computers,
assuming you have a single public IP address, the router must be set up
to use Network Address/Port Translation (NAPT, sometimes referred to as
"NAT"). This allows a single public IP address to be shared between
multiple computers on your network.

Each computer on the network must have a unique private IP address, and
the router expects it to be within a particular range of addresses which
it will define. For most routers, this is likely to limited to a range
of up to 254 addresses starting somehwere like 192.168.0.1 or 10.0.0.1
(possibly varying the third component of the address). The specific
details vary between router brands/models, and may be configurable on
the router.

If you wanted to do so, you could configure everything manually, setting
up each computer to have a unique address in the range expected by the
router, and also set up the correct subnet mask, router address and
other settings such as the DNS server.

This is a lot of work, and it is easy to make mistakes.

To simplify things, the computers on the network can have their IP
settings configured automatically by the router, using a protocol known
as DHCP. When the computer connects to the network, it asks the router
for an IP address, and the router allocates one which isn't currently in
use. This is supplied to the computer along with the other settings I
mentioned above, which are sufficient to allow the computer to talk to
the router and the entire Internet.

To use DHCP, the router must be set up to operate as a DHCP server. Both
this and the NAPT setting will be done using your router's configuration
user interface, which is accessed with a web browser. Refer to the
documentation which came with your router for details.

Each computer must also be set up to get its IP settings from a DHCP
server. This is the default configuration for a Mac and for most
versions of Windows, so you shouldn't need to configure anything on the
computers unless you had previously entered customised configuration.

Once DHCP is set up correctly, each computer should be able to connect
to the Internet simply by plugging it into the router via an Ethernet
cable.

Establishing a wireless network is more complicated, because you have to
deal with issues like protocols, security settings and naming
conventions, which vary somewhat between manufacturers.  I haven't set
up a Linksys wireless router so I'll leave that for others to describe
in detail.