As almost everybody in Belgium, Europe and probably the rest of the world, most employees of Excentis are working from home in order to avoid spreading the Covid19 virus. For me this means being with 4 people, sharing the same rooms, food and ... Wi-Fi.
Lucky me, I have a small office space which I can use so I don’t disturb the others (or was it the other way around?). I’m quite happy working from there, but the first day I still encountered some issues. The first online meetings were not great as the video and audio quality was rather bad. Initially I thought that this was due to an overload of the services and access network – which might have been the case. But I experienced the same bad quality in the evening, so I knew I had to look at my own network. And I did not want to be laughed at by colleagues.
First step: look at the frequencies
When optimizing Wi-Fi networks, the first thing to look at is interference. The challenge there is to find a frequency which is not used by any near-by access point. When you are living in a detached house, this shouldn’t be that difficult. Finding a free frequency in an apartment will be more challenging – read impossible. In that case, you must find the least used frequency. Many access points have the option to do this automatically. I have chosen not to do this, but you can try and see if this works for you.
But how can you find the best frequency? There are many apps for your mobile devices which assist you in this. Depending on your level of experience, you can use apps like Wifiman, Wifi Analyser, ... These will visualize the different networks, the frequency they use and the signal strength at that location.
I configured my frequencies when I initially installed my Wi-Fi network. I checked the configuration, but it was still ok. I don’t have any other Wi-Fi signal nearby, so there was nobody to blame and I had to look at different options.
Second step: force your Wi-Fi clients to the closest access point
Before you start thinking I live in a giant villa, I don't. My ‘Wi-Fi network’ contains 2 access points. The basic idea is simple: I have an access point on the ground floor and one on the attic. The access point on the attic should cover the bedrooms and my little office space. The other AP should cover the kitchen, living room and our terrace. The problem was that my laptop kept connecting to the wrong access point. Did I have a broken AP on the attic? Should I buy another one?
With the same tools as we use for visualizing the frequencies, we can also show the signal strength of our APs. Those clearly showed that the AP on the attic was giving a better signal than the AP on the ground floor. But why was my laptop, smartphone, ... still connecting with the AP on the ground floor? This is what is called the ‘sticky Wi-Fi issue’. For the client, the Wi-Fi signal is still strong enough and there is no reason to move. You know there is a better signal but ultimately, it is the Wi-Fi client that decides. So, what can we do?
In order to solve this problem, you give those clients a worse signal. This by forcing the AP to ignore those clients. My AP allows me to ignore clients for which the signal strength is below a certain level. Those clients will start looking for a different signal as they don’t receive messages from the AP. Those clients will then find the second AP. I configured this level at -75dBm, and this solved my problem right away. But this level can be different for every home
The result is great: overall Wi-Fi quality is now better on the first floor. It might have some consequences if we are sitting in the garden or on the terrace, but I will leave it like this for now.