Best channel allocation strategy for homogeneous wifi network with ap-one in-wall's and peplink balance WLAN controller


#1

Hi –

We’ve recently switched one of our sites to the new pepwave ap-one in-wall’s from an older cisco/linksys business wap line. The new setup is very slick – very easy to deploy and manage. However I’ve got what could only be described as a challenging wifi environment and I’m looking for advice on the right channel assignment strategies for my equipment/environment combination.

I’m deploying wifi on a ship which is almost entirely made of metal – the metal obviously is not particularly great for RF – so we tend to have a fair number of WAPs relatively close together to service different areas of the ship – with signal strength varying significantly as bulkhead doors are open/closed for various reasons. For this reason, the ap’s are deployed relatively close to each other.

A few questions:

  1. It’s not all that clear to me the best choice for AP channel assignment … Via the balance WLAN controller I can specify for each ‘profile’ either a specific channel or ‘auto’ with a set of channels – what’s the right choice for an all-pepwave with wlan controller managed environment? Historically from my experience with other products the ‘auto channel assignment’ algorithms were never particularly effective – so it was wiser with our previous ap’s to manually assign the channels to try to achieve the most frequency separation between the nearest/most interfering access points … But I’m wondering if ‘auto’ assignment as implemented in the balance wlan controller is appropriate for my environment now… It seems to me like the algorithm for channel assignment could be ‘much more right’ than what could be achieved in the past with non-centrally managed ap’s …

  2. I only have and only need a single profile for all the ap-one’s hanging off my balance router – if I do need to do manual channel assignment for each AP how do I do that – do I end up having to make a different profile for each AP?

  3. Same questions regarding dynamic power adjustments … It seems like power=dynamic:auto is appropriate for an environment like mine with a significant potential for ap-crosstalk … Also – if I choose to enable Power=dynamic:manual or Power=dynamic:auto, I am also able to set an option called ‘coverage redundancy’ with values ‘high, medium, or low’ … Are there any details on what the coverage redundancy setting does? – I can’t find it described anywhere in the manual …

  4. What does the ‘preferred frequency’ option do? I thought it was essentially controlling ‘band steering’ until I noticed the ‘band steering’ setting specific to each SSID …

I’ve been operating with a profile configured with dynamic channel assignment and power:max for awhile now … I notice that the AP’s are changing channels frequently – usually once or twice a minute in an environment with 4 AP-one’s … Is this the auto-channel algorithm moving the channel conflicts from ap to ap in some infinite game of ‘pass the interference’ …?

Many thanks,
Ben


#2

Hi Ben,

Thank you for your information. It is very challenging to implement wifi network on a metallic environment, especially your environment is changing (open/close the metallic doors).

Before answering your questions, here is the explanation of auto power and auto channel on our WLAN controller (WLC).
Auto power:
Each AP detects the signal strengths of neighbor APs (the access points managed by the same WLC) in the environment. WLC gathers this information and calculate the transmitting power of each AP base on the neighbors’ signal strength. If detected neighbor AP count of an AP is less than 3, the power of that AP will become maximum. The auto power action will be conducted every 10 minutes if you select “power=dynamic:auto”.

Auto channel:
When AP activates, it selects the best channel automatically according to its background scanning result, which base on the channel utilization of each channel.
The role of WLC is to resolve any channel conflicts between the managed APs. Same as auto power, WLC’s logic bases on neighbor AP detection result of each AP. WLC tries to select the best non-adjacent channels for each AP to it’s neighbor.
However, WLC will not take any action until users trigger the “Dynamic Channel Assignment” in the “Toolbox” manually.

For your questions:

  1. Our auto channel + WLC channel conflict avoidance should provide the best channel selection for each AP. However, you have to manually trigger the “Dynamic Channel Assignment” every time the AP boot up in your case.
    The auto power should work well if you are using 4 APs and placed close together.

  2. You can manually assign channel to each AP at “AP” -> “AP Status” -> “Details” button of each AP -> “Channel” (Provided that you are using firmware 6.1.0)

  3. Coverage redundancy refers to the expected overlapping coverage between AP. This will affect the dynamic power result, “high” would cause the higher tx power.

  4. “Preferred Frequency” in AP profile is designed for some of our AP products those support dual band but can only activate one radio band at a time.
    “Band Steering” is useful for APs which support both 2.4GHz and 5Ghz at the same time. Wireless clients which have dual band capability will probably connect to 5GHz band if band steering is enabled.

For the question about channel changing frequently on AP, please create support ticket via the following URL.
http://cs.peplink.com/contact/support

Thanks,
Lewis


#3

Thanks for the response Lewis. Based on your info, I think auto power and manual channel assignment make the most sense for my environment.

I’ve tried doing manual channel assignment but am getting the message ‘error unknown section’ when I attempt to save the change … Any clues about that? I’m using balance firmware 6.1.0 with pepwave ap-one in-wall’s with firmware 3.4.0…

Here’s an image of the error:



#4

Would you please turn on Remote Assistance of your unit(Both AP One and Balance)? And then, please create support ticket here. We would like to look the issue further.