Most office Wi-Fi problems come down to planning, not equipment. Here is how the three bands behave, what interferes with them, and the three things to get right in any deployment.
Three bands, three behaviours
Wi-Fi runs on three frequency bands: 2.4 GHz, 5 GHz and 6 GHz. Which one a device uses depends on the device and on where it is in the office.
- 2.4 GHz is the oldest and most widely supported. It travels furthest and gets through walls best. But it is narrow: of its 13 channels, only three (1, 6 and 11) don't overlap. It is also shared with neighbouring networks, Bluetooth and even the office microwave.
- 5 GHz has far more channels and far more speed. It doesn't travel as far or get through dense materials as well. Most modern laptops and phones prefer it and fall back to 2.4 GHz when the signal gets weak.
- 6 GHz is the newest band, used by Wi-Fi 6E and Wi-Fi 7 devices. In the UAE it is open for indoor Wi-Fi. Older devices can't use it.
What gets in the way
Concrete, lift cores, metal shelving and even fish tanks weaken the signal. Clear glass partitions are rarely the problem; dense materials are. A plasterboard wall and a concrete wall behave very differently, so there is no single rule for how many walls Wi-Fi will pass through.
Interference doesn't only come from inside the building. One of our clients lost Wi-Fi at the same time every day. The cause was radar from a nearby airport. Part of the 5 GHz band is shared with radar, and access points using those channels must move off them when they detect it, which drops connected devices.
Most problems come down to planning
In our experience, most office Wi-Fi issues aren't caused by unsuitable equipment. They come from equipment deployed without a survey: a "fire and hope" approach. That is why we start with:
- A radio survey. What is already in the air, where the interference is and where the dead spots will be.
- A design based on the findings. An office of 50 to 80 people needs a very different design from one of four. More access points don't automatically mean better Wi-Fi. If too many people share an access point that isn't built for that load, everyone suffers, not just a few.
Wi-Fi hygiene
Access points near each other need channels that don't overlap. Otherwise people lose connections even with the right equipment. Managing access points centrally, from a WLAN controller or the cloud, sets channels and power automatically, steers devices to the best band and helps them roam cleanly between access points.
Don't forget the cabling behind it. A good access point on poor cabling, or on a switch that can't give it enough power, will never perform properly.
The three things to get right
- The specification and number of access points. Is it right for the number of people in your office?
- The radio environment. Are channels planned so they don't overlap, and are you making the most of 5 GHz and 6 GHz rather than relying on 2.4 GHz?
- The use case. Video calls, email, streaming? That decides your quality of service (QoS) policies. QoS gives priority to Teams, Zoom and voice calls so a call doesn't drop while you are trying to close a deal, while a text message can wait a fraction of a second.
Full transcript
Morning guys, today's going to be a little bit of a science and physics lesson. So if you're not interested in Wi-Fi, I turn off now. However, if you currently have or have ever had a Wi-Fi issue, stick around, you're going to learn some stuff and it might even make you look like the office hero. So Wi-Fi basically operates on three different bands, as we call them.
We have 2.4 gigahertz, 5 gigahertz and we also have 6 gigahertz, which is the newer one. 6E and Wi-Fi 7 devices work on that. So unless you've got like the latest iPhone or the latest laptop, you're probably using 5 and 2.4. Now why is that important to know?
Because depending on where you are in the office and what device you're using, that will define which one you are relying on. 2.4, the oldest one, it's ubiquitous, it's the most widely supported and it travels the furthest. It permeates solid objects better than the other two. But the problem is that that band, it's quite narrow, there's only three non-overlapping channels in that band.
It's either 1, 6 or 11. So although there's 13 channels, you can only use those three without there being some interference between those APs, right? So you might suddenly get a Wi-Fi dropout or a terminated connection or very poor overall performance unless you've distributed your devices on those channels correctly and we'll explain that better in a little bit. 5 gigahertz, much better, much broader, many more opportunities for non-overlapping channels.
It's what most modern laptops and phones are using but it doesn't permeate solid objects as well. We actually had one client whose Wi-Fi was being disrupted because the radar from a nearby airport would emit at the same time every day and knock out the Wi-Fi in their office. So yes, interference doesn't just come from inside the house and this is why you need an informed partner who can audit and survey the radio environments in your offices. The majority of Wi-Fi issues that we see are generally down to a poor understanding of the technology.
It's not that the devices are not appropriate for the job, it's just that they've been deployed incorrectly in this kind of fire and hope for the best type situation. So, one of the ways that we help is by doing that survey and that assessment but we also specify the access points against the unique findings of that audit and so in understanding your use case best, we know what to propose so that it is not over-specified as much as underspecified. If you're in an office with like 50, 60, 80 people, the design that we specify will be different from a small SME deployment of two, three or four, right? More access points for more density does not necessarily mean a better level of quality service.
And so, if you've got too many users on one access point and it's not built for that level of traffic, everyone is going to suffer. It won't be a situation where one or two people are first past the post, it's everyone who is going to suffer as a result of the inappropriateness of that solution. The second thing to think about, Wi-Fi hygiene. If you haven't planned your channels properly so that access points near each other aren't overlapping, then even with the right technology, people will still lose their connections.
That's why the access points should be managed centrally either by what we in the IT world call a WLAN controller or these days often from the cloud. Central management sets the channels and the power automatically so all you need to do is walk into the environment and enjoy the efficiency of it being outsourced to a specified piece of technology. And so, not discounting the actual cabling itself, you have to make sure that the quality of your cabling is good. So make sure that your terminations and your cabling for your APs is in tip top condition.
And so, the three things to think about in a Wi-Fi deployment is number one, the spec of the device. Is it appropriate for the amount of people that you have in your office? Number two, the radio environment. Do I have the right assortment of channels non-overlapping and am I using 2.4 or am I using 5 gigahertz?
And the third thing that we want to think about is the use case. Are you streaming? Are you on a video call? Are you on a voiceover IP call and on Teams or Zoom?
Or are you just sending a WhatsApp message? What we would like to do is set policies that define the quality of service depending on the kind of traffic that you're undertaking. What that basically means is that the WLAN controller or the network itself will observe the behaviour of the devices that are connected to it and not over spec in terms of the amount of bandwidth or availability that is given to a device that's only just, you know, sending a couple of text messages or emails back and forth as opposed to someone who sat in a glass box somewhere trying to close a deal over Teams. It's really important that you have the right partner who understands the niche of this Wi-Fi configuration problem to ensure that you don't face these issues at the crucial moments of your business's operations.
If you want to know more, get in touch with us. Hello at opsit.ae. If you'd like to see more content like this, hit me with the thumbs up. My name is Andrew Thomas.
We are OPS IT Infrastructure. Give us a shout. Let's speak soon.