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AFAIK, there are 13 channels for use in europe (non-overlapping being 1,7,13), North America only get 11 (1,6,11) and the lucky Japanese get 14.
Most wireless kit tends to be designed for the US market and thus will rarely allow channels above 11 to be selected, despite using european firmware and offering the option to set the region. Cisco is one of the manufacturers that does things 'correctly' so you get the extra channels.
This thread has come in very useful - I'd just like to see if my setup follows what you lot would think is suitable.
I've just 'inherited' our Wireless Network from the Admin network. The APs were installed and supported by Bromcom until we moved to Lesson Monitor in September last year.
I hadn't done anything with the wireless network since then as it had been working as normal. That was up until the last couple of weeks when a block of the school (filled with Wireless MacBooks, Science and Art teachers' laptops and 4x PGCE students w/ laptops on wireless) were afflicted with a wireless network problem.
After using NetStumbler (great program) to find that all the APs were on channels 11 and 6 and that the air was a cacophony of signal noise, I have moved each of the 20 APs onto the Curriculum Network, upgraded to the latest firmware and stuck them on channels 1,5,9 & 11. I do have Cisco APs and so could use 13 in place of 11, would this be advisable?
Why don't people spread the signals over all 13 channels? What are the benefits of something like a Bluesocket Controller and would you advise a purchase?
Cheers
Sam
So summarising what everybodies said and linked to -
In the UK we are allowed to use channels 1 to 13.
Most kit comes with default setup to use 1 to 11 and a some of it can't be changed.
And notwithstanding external factors:-
If you want to use non-overlapping channels then you need to use 1,6 and 11 if restricted by your equipment.
or
If you've got 13 ch APs and wireless cards you still only got 3 non-overlapping channel possibilities but you can choose which combination to use :-
1,6,11 / 1,6,12 / 1,6,13 / 1,7,12 / 1,7,13 / 1,8,13 / 2,7,12 / 2,7,13 / 2,8,13 or 3,8,13
and if you need 4 channels for your topology best to use
1,5,9,13
Yes?
regards
Simon
@mortstar: I would advise a Bluesocket controller - I love mine (which is possibly a little scary).
The Bluesocket controllers will manage the Cisco APs just fine.
Advantages of a controller are:
* Central, single-interface, for deployment and configuration of APs
* Easy firmware upgrades
* Added security layer
* Automatic channel and power selection
* Much more besides!
@Morstar: I would advise a Cisco controller - I just love mine (which is possibly a little scary).
erm ... what do you mean is there an echo in here?
;-)
But my Bluesocket one is blue!
Plus I paid for the controller which allows me to have as many APs as I like (upto approx. 400 concurrent connections - dependent upon encryption) and all the other bits (inbuilt RADIUS, authentication, etc., etc.) are there. None of this license for this, license for that business which really annoys me!
I want to buy a box and know that it will do everything I want it to without having to buy additional licenses for x,y and z!
Hello,
I find that 1,5,9,13 works fine in all the schools I have done surveys in, but the one thing you need to makes sure is that the clients can all see 13 channels as well. I have seen a number of schools where their latops must have had US wireless NIC's in them and they could not see channel 12 or 13.
If you are trying to get more bandwidth in a school you can turn down the power on most AP's. which means you can get more of them in one building before they overlap and start to affect each other, but this is more cost. The other way is to put bigger antenna on the AP's, up to 6/7dbi which would give greater coverage zones, but less potential bandwidth in the school building.
I feel that 11g can only support a maximum of 15 laptops efficiently in a building, when you get in a situation where 15 laptops are being used in two classrooms next door to each other (or on the floor above or below) 11g does not have the bandwidth capacity.
I would tend to recommend 11a for secondary schools as you can stick say two AP's in each classroom, and gurantee at least 50mb of usable bandwidth per classroom. The downside to this is that only new laptops are coming with 11a as standard on the motherboard.
Andrew
IF you buy at the higher end with management consoles and dumb APs you don't need channels a all just stick with the same one the console does the rest.
Wes