Nebula [AP]- Wireless Health & WiFi Aid

This article will explain how Access Point [AP] wireless health and WiFi Aid works in Nebula Control Center (NCC). It will show how to increase WiFi performance, what 6GHz/5GHz/2.4GHz Radio, Adaptive channel width, DCS, Client, Optimization aggressiveness as well as Wi-Fi Aid for network issues. connection problem overview, examples of WiFi failures, and what Wireless failure, DHCP failure, DNS failure, and Portal failure are.
 

Wireless Health

Wireless health is a Nebula professional (Pro) feature that lets you monitor your WiFi network's health (both Nebula devices and connected WiFi clients). 

• AP constantly monitoring non-WiFi interferences (AP will start operating this feature by upgrading to v7.10)
• Self-optimization behavior change on 5GHz radio 
• Wireless Health event log enhancements

You can improve the WiFi network performance by doing the following: 

• Enable DCS (Dynamic Channel Selection) to select a radio channel with least amount of interference
• Enable Client Steering to use a stronger WiFi signal
• Change channel bandwidth to reduce radio interference from other WiFi devices

Go to Monitor -> Access Point -> Wireless Health 

Auto Optimization Action

6G/5G/2.4G Radio - Select ON to enable and specify how to Nebula Device improves the WiFi network performance.

Adaptive channel width - Select this option to change the Nebula device channel bandwidth from 160 MHz to 80 MHz automatically to reduce the radio interference with other WiFi devices nearby. If this doesn't improve the performance, it will also enable DCS.

DCS (Dynamic Channel Selection) - Select this option to have the Nebula device scanning and choosing a radio channel that has least amount of interference

Client - Select ON to try to steer the WiFi clients that has poor health to a Nebula device or SSID with a strong signal. Client steering to improve the signal strength is done every 30 minutes. 

Optimization aggressiveness -  The level selected here decides the level of traffic rate and when the device takes action to improve the AP's WiFi network performance by postponing the actions implemented on APs until your network is less busy if the threshold is exceeded. 

• High - The Nebula device is postponing the action set when the access point network traffic is heavy
• Standard - The Nebula device is postponing the action set when the access point network traffic is medium.
• Low - The Nebula device is postponing the action set when the access point network traffic is low.

Reasons for poor wireless health could be related to: 
No IP given from DHCP server, roaming issues, channel interference by a very busy WiFi environment etc. 

These issues can be resolved by looking at this article: 

WiFi Performance - Best Practice for a Professional Deployment

WiFi Aid

Wi-Fi Aid is a Nebula professional (Pro) feature that lets you get a clear overview of network access issues. WiFi Aid includes a problem overview and historical statistics. Please note that this only summarizes the access issues of the WiFi network. If you're dealing with throughput issues or unstable connection, this page might only give you a hint, but check out Wireless Health for connection signal strength and channel utilization to further troubleshoot the throughput/instability issue.

Connection Problem Overview 

Here you can find the number of devices that are suffering from a connection failure as well as a categorization of the issue type for each station's last failure. Once a station successfully connects to the AP in the selected period, its past failures won't be counted anymore.  

Examples of when failures count

If Client 1 (C1) is first typing the wrong password in the first try, then tries again and connects to the AP with the correct password. But now it fails to get an IP address, it tries to connect again, but still fail to get an IP address. This will show as 1 DHCP failure (as shown below). 

If Client 2 (C2) connects to the AP with the correct password, but still fail to get an IP address. C2 then tries to connect using a static IP and DNS server and successfully reconnects and gets internet access. This will now show as 0 failures. 

In these two examples, you will find the failure overview as shown below:

Connection Problem Explanation

Below you will find a explanation of what these symbols mean and when it will be counted as a failure.

Wireless Failure – Client fail to associate with the SSID

This shows when the user has entered the wrong Password / 802.1X Auth. Fail / Client is blocked by functions.

The wireless connection failure, is any failure which makes the client can’t associate with the SSID. Such as wrong password, WPA-Enterprise authentication fail, and the client is blocked by any functions, such as load-balancing, legacy client, MAC filter, and so on.

DHCP Failure

This shows after a client sending DHCP-Discover, and there is no DHCP-ACK within 20 seconds.

The DHCP Failure is if the AP does not receive a DHCP ACK within 20 seconds, it will regard this client fail to get the IP address.

DNS Failure

This shows after a client sending DNS-Query, but there is no reply within 15 seconds.

After a client send the DNS Query, but there’s no DNS reply within 15 seconds, this client will regarded having the DNS issues. Please note that if the DNS server replies that the domain can’t be solved successfully, then this case will not be regarded as a failure, because the client and DNS server can negotiate with each other.

Portal Failure

This shows when the user has entered the wrong user credential / Auth. Timeout

For the Portal Failure, which simply identify the cases where clients fail the portal authentication, including that they might type the wrong password, or fail to connect with server, and so on. Please note that this will not identify whether a client is successfully redirected to the portal page. To identify the portal redirect issue, the easiest way is to ask client manually open a browser, and type “neverssl.com”, then they should see the portal login page.

Historical Failure Statistics 

Categorize all failure events into different dimensions

• Issued client number per SSID
• Issued client number per AP
• Issued number per client