How many AP to N hosts?

[fernando]

I need to design a WLAN for 200 hosts. So, how many access points (will use 802.11b) I will need? How should I calculate this?

And how should I configure them? They should be, each one, in a different channel, correct?

[gamccall]

The very rough rule of thumb is 30 users per access point. This would suggest that 7 APs would be needed to support your load, under normal usage; however, that's not the only issue.

If you're operating in 2.4GHz bandwidth, you only have 3(*) non-overlapping radio channels to allocate. Overlapping coverage from multiple APs on the same channel will ruin your performance, so you need to consider not only your number of users but also their geographic density. Will you be able to isolate your AP coverage using power tuning and shaped antennas so that you can cover your users without overlapping your fields, or are all 200 users sitting right on top of each other?

You do have the option to use 802.11a instead of b/g; this will give you a lot more flexibility for channel selection but will require your users to purchase a 5GHz adapter which they probably don't already have.

*4-channel schemes have been shown to function better than 3-channel schemes under some circumstances.

[fernando]

Hum... That's really a problem for me. The space there is "small"... Only 100 meters and have 160 machines...

I was planning to use 5 access points. The machines are for Web Development, so, they don't need too much bandwidth. 50 machines are for Networks Labs, so I was thinking to put 3 AP for the 50 hosts NetLabs and 2 AP for the 110 hosts WebDevel. What do you think about this?

And the real problem will be the overlapping channels... I think that will be a real problem, because the place is small, as I said... I would need to use only 3 APs or choose some directional antennas...

Any other idea? Is there another solution?

[gamccall]

There are really only 3 ways to handle a dense user population: get very creative with directional antennas and signal-strength tuning, switch to 802.11a, or run cables. You might wish to hire a specialist to survey your location and make recommendations.

[fernando]

I was thinking in put 3 AP 802.11g and the clients with 802.11b... i don't need high speed for the clients, but I need all of them connected with some good speed (1 or 2 Mbps is enough).

What do you think? Will it work?