cisco aironet 1100 weak signal with ipad2 iphone and blackberry

[power.srvi]

hi all,

in my company we have 40 cisco aironet 1100 without controller, the signal is good with laptops but is too weak with the iphone's ipads and blackberry.

Can some one help ?

regards

[johncaston_2 · Accepted solution]

Sounds to me that it might be time to upgrade your AP's - they're obsolete b/g models.

Something like the 1142a/b/g/n would be good - 802.11n also improves transmission to non-802.11n devices

The other things that you might like to look at is the AP density, a good rule of thumb is 1 AP per 450m2 for data and 1x AP per 280m2 for voice

You should also look at disabling 1,2,5.5 and 11Mbps throughput (802.11b) as this slows down 802.11g communications

Sent from Cisco Technical Support iPad App

[power.srvi]

hi,

thank you for the reply,

i also changed the channel, in this compagny we have 60 ap, in the zone with the channels set to 1-7 there is no problem

but when i connect to the channel 13 with iphone 3gs and 4g i pad and blackberry the signal is so weak.

when i put channel 8 at the place of the channel 13 the signal becaumes more storng.

I will alsio try with the setting that you gave me.

Thank you again for the reply i will take you up to date.

regards

[Scott Fella]

I don't know what country you have these AP's, but using channel 1, 6, and 11 is the norm. The iOS devices might not be able to use channel 13.

Thanks,

Scott Fella

Sent from my iPhone

[power.srvi]

we are using this access point in north africa, he model is aironet 1100 version

version 12.3

and we are using channels 2,7,13

so the wireless network was designed buy another compagny, so can you send me a good documentation about designing wireless network, best practices too.

also the 60 ap are not managed buy an wireless controller, it is necessary to use a controller ? if yes have you a good model.

thanks

[Scott Fella]

Well with the 1100's you are better off to migrate to newer AP's (capwap) and use a 5508-100. You can get a 5508-50 and a license for another 25 APs, but having two WLC is required for redundancy. If you look at basic wireless configuration, you would use channel 1, 6, and 11.

Thanks,

Scott Fella

Sent from my iPhone

[power.srvi]

thanks

[Scott Fella]

I would change channel 2 to channel 1, channel 7 to channel 6 and channel 13 to channel 11. Are the channels static or are they dynamic?

Thanks,

Scott Fella

Sent from my iPhone

[power.srvi]

how can i know that the channels are dynamic or static ?

here is a configuration sample:

version 12.3

no service pad

service timestamps debug datetime msec

service timestamps log datetime msec

service password-encryption

!

hostname xxxxxxxxxx

!

!

ip subnet-zero

!

!

no aaa new-model

!

dot11 ssid xxxxxxxxxxxxxx

   authentication open

   guest-mode

!

!

!

!

bridge irb

!

!

interface Dot11Radio0

no ip address

no ip route-cache

!

ssid xxxxxxxxxxxxxxx

!

short-slot-time

speed basic-1.0 basic-2.0 basic-5.5 6.0 9.0 basic-11.0 12.0 18.0 24.0 36.0 48.0

54.0

rts retries 100

packet retries 100

channel 2447

fragment-threshold 1000

station-role root

beacon period 2000

beacon dtim-period 50

no cdp enable

bridge-group 1

bridge-group 1 subscriber-loop-control

bridge-group 1 block-unknown-source

no bridge-group 1 source-learning

no bridge-group 1 unicast-flooding

bridge-group 1 spanning-disabled

[Scott Fella · Accepted solution]

channel 2447

This tells you it is static.

Thanks,

Scott Fella

Sent from my iPhone

[power.srvi]

thanks mr fella,

so its better to keep channels on static mode ?

[Scott Fella]

I would say yes, especially if it was surveyed and the other company decided what channels to use where. Just modify the channels which I posted previously.

Thanks,

Scott Fella

Sent from my iPhone

[johncaston_2]

Most countries support channels 1-13 and some also support 14 (but not many).

You can use channels 2,7 and 13 but the norm is to use 1, 6 and 11 - either way you only end up with 3 non-overlapping channels. These channels refer to the centre frequencies and 802.11 is wide-band so it will use several adjacent frequencies too, i.e. channel 2 will still overlap channel 1, so there's nothing to be gained by using 2,7 and 13 - personal preference really

When installing a controller-based wireless solution I prefer to leave DCA (Dynamic Channel Assignment) and TPC (Transmit Power Controller) enabled (default), as this lets the controller determine the optimal channel and power settings and it makes the solution more adaptable to changes in the environment, not to mention it's easier to manage.

In situations where I have interference from a specific device, e.g. radio mics, I would fix the channel for the neighbouring AP's but still let the rest find the optimum settings (also helps with with coverage holes if an AP fails)

As to why you're getting weak signals on some devices, probably more related to lower radio power - I would begin with doing a wireless site survey with something like AirMagnet Surveyor to produce a heatmap and see what your coverage is like

Hope that helps

Cheers,

John