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how does one avoid co-channel interference on dot11a solutions in EMEA ?

When deploying wireless access points on dot11b/g, co-channel interference can be minimized by appropriate manual choice of channel numbers across the physical site.

In the US, the same methodology applies for dot11a solutions, where manual frequency selection for an AP is an option.

However, Here in EMEA, with compulsory DFS for dot11a, there appears to be no manual control at all on channel selection.

The default behaviour as I understand it - is for an AP to pick a random channel during interface initialization, and then if no radar detected, continue to use that channel.

(This has hit us on one solution, where four APs in neighbouring rooms at a client site selected the same channel on startup - causing significant co-channel interference!)

So how does one avoid co-channel interference on dot11a solutions in EMEA ?

Do wireless LAN controllers (with thin APs) have an option to preselect dot11a channels before the DFS listen check ? (Rather than just a random choice)

The IDEAL solution, would be for Cisco to add the following option to its IOS syntax :-

Interface dot11radio1

Dfs band 2 3 4 block

Channel 36 preferred

Adding a preferred keyword option would allow co-channel interference to be avoided by design, whilst still allowing a DFS check to prevent wireless interference.

If I wanted to pursue the inclusion of this new option into AP IOS, what would be the best method in tackling this?

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Re: how does one avoid co-channel interference on dot11a solutio

I don't have an answer for you but I do have a question. I have been researching the issue of which channels in the 2.4 band are permitted according to law in the various countries in Europe. We have offices in Germany, France, Spain, Netherlands and England and I was wondering which channels we are permitted to use. Do you know or could you point me to a document I could read?

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