For ADSL, all you would need is an Ethernet port on your laptop.
My ADSL modem can use Ethernet. And you can get PCCard or PCMCIA
Ethernet cards, if the laptop currently lacks Ethernet.
An alternative hardware solution, is an ADSL modem with a USB
interface. They make such things, but I would not buy one. I
much prefer something like Ethernet.
Another issue, is protocols. ADSL providers like the PPP protocol,
which adds overhead to the communications stream. It gives them
management flexibility in their networking, which is why they use it.
My ADSL modem and my ISP, use PPPOE (point to point protocol over
Ethernet). The packets that come out of the modem, cannot be used
directly. Instead, the packets carry a data stream very similar to
the stream seen with a dialup modem.
If I connect my ADSL modem directly to my computer, my ISP provides
a software CD, which contains PPPOE conversion software. That
means code is running all the time on the computer. Now, when I
first got ADSL, I had trouble with the program they provided.
(Crash city. Paul not happy.)
You can buy a router box (one WAN port, multiple LAN ports), which
will have as part of its feature set, the handling of PPPOE. That
is what I am using currently. I started with a Linksys BEFSR41 to
do the job, but since switched to a "bargain" brand which is
actually more stable. The bargain was 1/10th the price of the
BEFSR41. Check for PPPOE in the feature set.
At this point in time, you should be able to find a combined ADSL
modem and router (one simple box), with wired LAN ports and perhaps
even wireless capability. That will handle all this protocol nonsense,
allowing your computer to be free of "foreign" software. To use such a
product, you take you favorite web browser, enter the IP address
of the modem/router in the URL dialog, and voila, you're connected to a
web server inside the modem/router. You set up your ADSL account
and password in there, and one click of a button, and the
ADSL modem/router connects to the ISP. From then on, until you
end the session, the computer thinks it is on a LAN. The computer
will use a network setting of "DHCP", and using that protocol,
it will automatically get its info from the modem/router box.
DHCP is what I use on mine, so no IP address info or netmask
need to be entered in the computer's networking control panel.
Just the DHCP thing is needed.
Now, if you had an ADSL modem with just a USB interface on it,
then you're back to using some kind of software to do the
protocol conversion into something useful.
In the case of the ADSL modem/router, there is a second function
of some value. The router uses NAT (network address translation).
See "Benefits" section here for details.
http://en.wikipedia.org/wiki/Network_address_translation
In summary:
1) Ethernet = good
2) Combined modem/router = no ISP software installed on your computer =
good
3) USB = bad
And if the ISP insists on using their software, ask one of the
newsgroups here whether it is really necessary. Chances are,
you won't need it, once you own the right hardware.
HTH
Paul
