Wireless N deployment scenario

klein425 · ‎06-04-2009

When designing a Wireless N network to support both B/G and N clients I've come up with the following:

1.) Dedicate the 5.0GHz radio for N giving you 9 non-overlapping channels to work with and allowing clients to connect at 300Mbps (when 40MHz channels).

2.) Use the 2.4GHz frequency as legacy B/G access for all other clients. If we wanted 300Mbps speeds on the 2.4GHz radio we would only have 1 non-overlapping channel to work with (when using 40MHz channels).

Are my assumptions correct or does anyone else have a better design?

Thanks!

phillip.vansickle · ‎06-04-2009

I was told by Cisco engineers to run 40 MHZ channel bonded N on the 5 Ghz side allowing speeds of up to 300 Mbps and regular N (20 mhz channel width) on the 2.4 side (allows up to 144 Mbps).

I have deployed this scenario in a threes tory building with 12 1140 AP's and it seems to work well.

I run 4404 controllers with 5.2 code.

Most of my clients seem to associate on the 2.4 side. I see a few A clients and rarely anyone running 5 Ghz N. Most of the laptops we use do not have N NIC cards though.

I don't advertise N rate speeds as I deployed N for the ability to deal with mulitpath issues and improve conditions for legacy A/B/G clients. So long as the users get a good connection with a halfway decent data rate...it meets the requirements (and most users will not notice any slownes)

Also, 5 Ghz just does not have the coverage that 2.4 ghz does (I just don't have the budget to deploy all the access points that I would like to...so they are spread out a bit more than I would like).

Curious what others have to say about this....

Leo Laohoo · ‎06-04-2009

802.11n Design and Deployment Guidelines

http://www.cisco.com/en/US/solutions/collateral/ns340/ns394/ns348/ns767/white_paper_80211n_design_and_deployment_guidelines.html