If you intend to share files on your LAN, you will only want one router for
the whole setup.

That router (wired or wireless) gets connected to the DSL modem.

You can then run a cable to a wireless access point upstairs and a cable to
a wireless access point downstairs. Both wireless access points should be
set to operate on different channels (e.g., 1 and 6).

In this setup, your current Microsoft router can serve as both the router
and the upstairs wireless access point.

You can connect an ethernet switch (quite cheap) downstairs to have
additional ethernet ports. You would connect the downstairs access point to
one of them. You can also connect a wireless router instead of a wireless
access point downstairs, but you may need to connect it through a LAN port
(and not the WAN port), you may need to use a crossover cable for this, and
you will have to turn off its DHCP server (you do not want two active DHCP
servers on a LAN). Alternatively, you could connect the downstairs router
through its WAN port, but then the downstairs computers would be behind two
layers of NAT, which is superfluous (in addition, NAT only passes IP
traffic, which causes problems when sharing files with LAN protocols because
the computers connected to this router may not see the computers connected
to the upstairs router).

-Yves

"noydb" <noydb@yahoo.com> wrote in message
news:4tetk1tle0ol81ro7ju8bpno75da34q3q9@4ax.com...
> Forgive me if this question seems nonsensical.
> I'm a borderline clueless newbie in this field.
>
> I have a DSL connection connected to a modem in the upstairs part of
> my house.
> That modem is also connected to my desktop system. That modem is also
> connected to a Microsoft MD-500 wireless router. I can use my laptop
> anywhere upstairs in the house with this setup.
> However, I can't connect anywhere downstairs.
> My home is a very old and very sturdy building with lots of very
> thick walls and brick, concrete and steel everywhere.
>
> My proposed solution is to run a CAT-5 (or CAT-6 ?) cable from the
> router upstairs to a central location downstairs, and then hook up an
> additional router downstairs. I would then be able to connect
> wirelessly (on different laptops) anywhere downstairs.
>
> Is this a feasable situation ?
> Would the two routers conflict with each other ?
> The intallation software is of particular concern.
> Could I put both installations on the same desktop PC ?
>
> I've chosen the Belkin Pre-N modem for downstairs since it is
> supposed to have exemplary range, and like I said, downstairs is
> fraught with brick and steel.
> Will this router conflict with the Microsoft one ?
> (actually linksys I believe).
>
> The Belkin is supposed to be compatible with 802.11b which is what I
> believe the Microsoft one is.
>
> I've concluded that this whole proposition will be either really
> simple or diabolically complicated.
> I thought I'd run it by the experts in here before taking the plunge.
>
> Any comments, advice, and warnings would be greatly appreciated.
> Thanks so much, --N