Technical Discussion
  >> Linux Issues


Register (or login) on our website and you will not see this ad.


Pages in this thread: 1 | 2 | 3 | [4] | (show all)   Print Thread
Standard User ukhardy07
(fountain of knowledge) Fri 28-Dec-12 00:06:22
Print Post

Re: Broadcom wireless driver detects other routers except mi


[re: mrdigital03] [link to this post]
 
You are mistaken about 13 being better.
Here's an example...
If a neighbour is using 6 and another using 11.
If you then use channel 8, this is wose than you using 6 or 11.

Why? Because you are bang in the middle of interference from BOTH 6 and 11.

If you use 6 or 11 your router will be on the same channel as a neighbours yes.
BUT it will try not to transmit data at the same time as the neighbours, so you avoid wireless collisions and data needing to be sent over and over...

On channel 8 you are invisible to 6 and 11's routers. You get interference from both and your data collides with theirs mid-air. It's overall going to degrade their network performance AND yours.

SIMILARY

Using channel 13. You get interference from 11. You get collisions mid air. It's worse than actually sharing the same channel...

Hence why we don't see channel 1,2,3,4,5,6,7 etc all being used.
It's done methodically to avoid interference.

1 6 or 11 will work for you.

If 1 is dropping out use 6 or 11 etc.

Channel 1 doesn't overlap with 6. So if the issues are on channel 6 they wont be on channel 1.

The admin may have used say channel 3 or 8 like in the example above. This would cause more issues and possibly drop outs. Afterall they're using 13 which is bad practice.

Edited by ukhardy07 (Fri 28-Dec-12 00:08:39)

Standard User Uilebheist
(legend) Fri 28-Dec-12 07:05:08
Print Post

Re: Broadcom wireless driver detects other routers except mi


[re: ukhardy07] [link to this post]
 
That assumes that other routers in the area are set up correctly...
I was visiting some friends over Christmas and they had constant wireless drop outs, they tried 1, 6, and 11 and they were all bad. A quick scan revealed a home hub somewhere in the vicinity broadcasting on channel 8 with the power of a small radio station. Well, that explains problems on both 6 and 11... Then there was something else causing problems to both 1 and 6.
They switched to 13, and had no problems.
Standard User yarwell
(sensei) Fri 28-Dec-12 09:10:38
Print Post

Re: Broadcom wireless driver detects other routers except mi


[re: Uilebheist] [link to this post]
 
the modern trend of setting routers to auto-select channels looks to be putting a lot of them onto 4, 8 and similar channels. It would have been nice if the auto selection was from 1,5,9 and 13 or 1,6 and 11 not "any old channel" - more dumbing down.

--

Phil

MaxDSL - goes as fast as it can and doesn't read the line checker first.

MaxDSL diagnostics


Register (or login) on our website and you will not see this ad.

Standard User yarwell
(sensei) Fri 28-Dec-12 09:20:50
Print Post

Re: Broadcom wireless driver detects other routers except mi


[re: mrdigital03] [link to this post]
 
[ 137.760006] cfg80211: Calling CRDA to update world regulatory domain
[ 137.795136] cfg80211: World regulatory domain updated:
[ 137.795145] cfg80211: (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)
[ 137.795151] cfg80211: (2402000 KHz - 2472000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
[ 137.795156] cfg80211: (2457000 KHz - 2482000 KHz @ 20000 KHz), (300 mBi, 2000 mBm)
[ 137.795160] cfg80211: (2474000 KHz - 2494000 KHz @ 20000 KHz), (300 mBi, 2000 mBm)
[ 137.795165] cfg80211: (5170000 KHz - 5250000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
[ 137.795169] cfg80211: (5735000 KHz - 5835000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
[ 839.717684] cfg80211: Calling CRDA for country: GB
[ 839.721487] cfg80211: Regulatory domain changed to country: GB
[ 839.721490] cfg80211: (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)
[ 839.721492] cfg80211: (2402000 KHz - 2482000 KHz @ 40000 KHz), (N/A, 2000 mBm)


The world list does include the GB frequencies, albeit with a different channel width. "World" also includes Ch14 for the Japs.

--

Phil

MaxDSL - goes as fast as it can and doesn't read the line checker first.

MaxDSL diagnostics
Standard User ukhardy07
(fountain of knowledge) Fri 28-Dec-12 16:41:54
Print Post

Re: Broadcom wireless driver detects other routers except mi


[re: yarwell] [link to this post]
 
In reply to a post by yarwell:
the modern trend of setting routers to auto-select channels looks to be putting a lot of them onto 4, 8 and similar channels. It would have been nice if the auto selection was from 1,5,9 and 13 or 1,6 and 11 not "any old channel" - more dumbing down.


The auto selection usually chooses 1, 6 or 11 unless there's already devices using other channels.

For instance if somethings using channel 2 then auto is unlikely to use 1 or 6, it might then choose channel 8. The something on channel 2 can even be a doorbell or AV sender nowadays...

Auto generally chooses 1 6 or 11 though.
Standard User ukhardy07
(fountain of knowledge) Fri 28-Dec-12 16:47:55
Print Post

Re: Broadcom wireless driver detects other routers except mi


[re: Uilebheist] [link to this post]
 
Yes if something is using say channel 8 it causes major issues.

It causes problems on channels 6 and 11.
& channel 1 is prone to issues too. This is because doorbells, av senders, baby monitors etc generally use lower channels. These aren't friendly like routers are. Having a router and a doorbell on the same channel is far more likely to cause issues than having 3 routers on the same channel...So channel 1 can be quite problematic in many situations.

Having several routers on the same channel is generally fine. It's the other devices that cause the major problems..

Often channel 1 appears free as there's no routers using it but it's crammed full of other devices such as these AV receivers & cordless landlines.

Hence why many routers on AUTO channel mode select channel 6 or 11 even when 1 appears free. The routers detecting the interference on channel 1 from e.g the doorbell and moving on.

Using channel 8 causes problems on 6 and 11. Then often channel 1 is already problematic due to the cordless phones etc. In this case the whole frequency is difficult to use.
Standard User yarwell
(sensei) Fri 28-Dec-12 17:01:34
Print Post

Re: Broadcom wireless driver detects other routers except mi


[re: ukhardy07] [link to this post]
 
UK cordless phones are generally DECT and well below the frequency of WiFi - below 2 GHz from memory.

--

Phil

MaxDSL - goes as fast as it can and doesn't read the line checker first.

MaxDSL diagnostics
Standard User ukhardy07
(fountain of knowledge) Fri 28-Dec-12 18:19:48
Print Post

Re: Broadcom wireless driver detects other routers except mi


[re: yarwell] [link to this post]
 
This is true. If placed close to the router they can still impact though.
Much like the vodafone sure signal can.
Standard User mrdigital03
(newbie) Wed 02-Jan-13 23:10:19
Print Post

Re: Broadcom wireless driver detects other routers except mi


[re: Uilebheist] [link to this post]
 
UPDATE: I finally got it working. It was infact to do with the router using channel 13. (which many of you did suggest)

Stumbled across some interesting facts though; 1. Besides changing the regulatory settings (to JAPAN, as suggested before) you can still change just the channel manually using IWCONFIG and IW (you can find more info on their dev. sites)

Also after doing tedious research realised that the manufacturer (Broadcom) actually locked CHANNEL 12-13. So I could not switch to it using IWCONFIG or IW. Anyways in the end manage to convince my router admin to drop the channel to 11 which resolved the issue.

Thanks for your help guys!
Standard User Uilebheist
(legend) Thu 03-Jan-13 08:21:34
Print Post

Re: Broadcom wireless driver detects other routers except mi


[re: mrdigital03] [link to this post]
 
Thanks for coming back and letting us know.
Pages in this thread: 1 | 2 | 3 | [4] | (show all)   Print Thread

Jump to