Firstly I would say using the same channel is a bad idea...
I to disagree with the advice here of using 1, 5, 9, 13 however. It's not terrible advice but most home routers will be on Auto and will default to 1, 6 and 11, so best to stick with this. Also a lot of devices sold in the UK will not work on channel 13 as they have a USA configuration, so this could mean those near to a 13 point end up getting poor reception as they are forced onto a router much further away not using 13.
Around 30% of devices I've used do not see channel 13 due to restrictions worldwide on this channel. So using this is a big no-no.
Using 1, 5, 9, 13
1 overlaps with 5, 5 overlaps with 9, 9 overlaps with 13. So that in itself could be problematic.
Then add home users into the mix (as it's likely in parts of the hotel a neighbours WiFi will be seen). These will be on 1, 6 or 11.
5 will overlap with 1 and 6.
9 will overlap with 6 and 11
13 will overlap with 11.
You are much better to just use 1, 6 and 11. As none of these channels overlap with one another. Also if a neighbour has a router on 1, 6 or 11 it's actually better to use the same channel as them than an overlapping one.
E.g. neighbour on channel 1, you are better to use channel 1 than channel 2. Having a router on 1 and another router on 2 will cause more collisions in the air and retransmitting of data than having both on channel 1.
Ideally you would use channel 6 as this doesn't overlap with channel 1 at all.
Hence 1, 6 and 11 are ideal as no collisions between the channels. This is why home equipment defaults to these channels.
To sum up virtually all businesses, hotels etc in the UK will use 1, 6 and 11.
Assuming a straight line you would put 1st router on 1, 2nd on 6, 3rd on 11. Then back to 1, 6 and 11. This way the crosstalk will be minimal. As the 1st router on channel 1 will be a whole 2 routers distance from the 2nd on 1. So they probably wont have any crosstalk at all.
The 2nd router on channel 6 will have no crosstalk with the 1st router on channel 1 or the third router on channel 11.
Having a setup like this 1, 5, 9, 13
The 1st router will have crosstalk with the 2nd router
The 2nd router will have crosstalk with the 1st router and the 3rd router
The 3rd router will have crosstalk with the 2nd router and the 4th router
The 4th router will have crosstalk with the 3rd router.
Do you see why 1, 6 and 11 MAY work better here. It reduces the crosstalk which may or may not cause issues.
Also it prevents issues with channel 13 where a large chunk of devices are unable to see this channel.
Having them all on 6 may work ok but speeds may be severely reduced or there could be too much interference and you may just be unable to connect at all.
Edited by ukhardy07 (Thu 19-Jun-14 02:12:54)