WLAN deployment across 3 floors without cable

Question

I have a customer looking to install a wireless network across 3 floors with full coverage on each floor. 2 ssid's are needed one for guest use and one for their business use. The top floor is where the server and demarc is located. The top floor is very small in relative size to the lower 2 floors.
It is a very old historic building and they refuse to run cable (drilling of holes...)
They will need bandwidth to support 12 pos systems (varied throughout the building) running off of the server (terminal services). They will also need enough bandwidth for the guest ssid (internet use).
Installing a lot of ap's as repeaters will reduce the available bandwidth. What options are available?

Answer 1

Keep in mind, you'll need a solid site survey to back up any recommendations made.
That being said, probably your best would be a dual radio AP, where the 802.11g/b radio is for client use, and the 802.11a radio would act as a wireless backbone.
If you use a 1200 series, you'd want one AP (per floor) located in / near the stairway and/or elevator such that you can use it as a "raceway" for the 802.11a signal.
Depending on the size and layout of the floor (wide open, partitioned, trees/flowers/hanging decorations), you can perhaps cover the area with ~2-3 APs (each set for a different 802.11g channel: 1, 6, or 11 preferred).
You should stagger the AP channel assignments per floor such that the AP directly above or below is using a different channel.
This is greatly simplified. More details would be helpful (like the square footage of the each floor, and the general layout, are there going to be any mobile clients, or all fixed location POS stations?).
and, again, you must do a good site survey to find out how many APS would be needed. If you need more than three per floor, then it would probably be better to use the 802.11a radio for clients and the 802.11g radios for the "backbone" .... 802.11a has more channels, and none of them overlap.
Good Luck
Scott