[aclug-L] Re: ADSL, SWBell & Linux

[Steven Saner <ssaner@xxxxxxxxxxxxxxx>]

On Sat, Jan 29, 2000 at 11:57:51AM -0600, Carl D Cravens wrote:
> On 28 Jan 2000, John Goerzen wrote:
> 
> > Anyway, there should be no problem with Linux.  They may claim that
> > Linux is not "supported" but it works fine.  The ADSL modem comes with 
> > a crossover UTP cable but with a standard cable you can hook it to
> > your hub (10Mb/s).  Just get the IP range, netmask, and default
> > gateway from them and configure it just like normal Ethernet.
> 
> Ur... I hadn't thought about this.  I don't have a hub... I'm running
> coax.  Am I going to have to upgrade my network to connect to the ADSL
> modem?  
>
> --
> Carl D Cravens (raven@xxxxxxxxxxx)
> My reality check just bounced.
> 


Well, this depends on how the service is provisioned. There are a
number of different ways ADSL service can work. The way I *think* SWB
is doing it now (and the way SouthWind plans to do it at least at
first) is to provision the service as a bridged network. This means,
that in a certain sense you have an Ethernet wire coming to your
house from the provider. If they allow you say 5 IP addresses, the way
to use it is to connect the ADSL modem directly into a hub and then
connect 5 computers to that hub. There is no routing device in this
case. Now another way the service could be provisioned is to have a
single IP address and you plug a routing device (a computer running
linux) into the ADSL modem on one interface, and then plug the rest of
your network into the other interface of the router. This router could
then either be doing NAT (ip masq) or the provider could route a
netblock of whatever size to you.

So, to more directly answer your question. If you plan to get several
IP addresses and they are provisioned as a bridged network, then yes
you might have to get a hub to plug the ADSL modem into and all of your
computers into. If, however, you are only going to get one IP address,
or the provider is going to route a netblock to you, then you will
need a second NIC in your "router" that has a 10baseT port to go to
the modem. The other NIC can be coax if you want.

Now, there is yet another way that ADSL service can be
provisioned. That is PPP over Ethernet. I believe someone on this list
said that this is what they were doing. I am curious who you are
getting the Internet service from. Is SWB doing this? In this case you
would need a NIC in your "router" connected to the ADSL modem. You
would then need to run a PPP client on that router to establish
connection with the provider.


Steve.