Can I Use DFS Channels on my Wi-Fi Network?

We’ve recently started to see a rise in customers using DFS channels when operating their Wi-Fi networks, so thought we would write an article all about it in case it’s also helpful for your own network.

What is DFS?

DFS is Dynamic Frequency Selection and is a type of Wi-Fi function that allows WLANs to use 5GHz frequencies (which are reserved for radar, for example, the military, satellite or weather).

What is the benefit of using DFS channels for Wi-Fi?

We’ve written before about how you can improve your Wi-Fi and prevent interference by utilising different channels. The main benefit of using DFS channels taps into this. You can increase the number of available Wi-Fi channels by using DFS channels to use these less-used frequencies.

How can I utilise DFS channels on my Wi-Fi network?

The first thing you need to do if you are wanting to use DFS channels, is to check that your wireless access points and wireless clients support the necessary functionality.

The 5GHz spectrum in the UK is broken into 3 different bands and runs from 5150MHz (5.15GHz) to 5850MHz (5.85GHz). The bands are as follows:

Band A

  • Channels 36 – 64
  • This is used only for Indoor wireless
  • Does not require a license

Band B

  • Channels 100 – 140
  • Can be used both inside and outside
  • Does not require a license
  • Hardware must conform to DFS standards and be DFS enabled

Band C

  • Channels 149 – 161
  • Can only be used outside
  • Requires a license from Ofcom
  • Hardware must conform to DFS standards and be DFS enabled

 

 

Checking DFS Channel Availability

When you enable DFS, the Wi-Fi access points will need to verify that any radar in the proximity is not using DFS frequencies. This is a process called Channel Availability Check and is carried out during the boot process of an AP as well as during normal operations.

Should an AP detect that a local radar is using a certain DFS channel, it will automatically exclude that channel for this list of available ones. This will last for 30 minutes after which time the AP will check again to see if the channel can be used for Wi-Fi transmissions. You’ll be pleased to know that this exclusion of unavailable channels has very little impact on Wi-Fi clients.

DFS channels are not immediately available when an AP boots. This is because the Channel Availability Check can take anywhere between 1 minute and 10 minutes during the boot process.

 

What happens if an AP detects radar use during normal operations?

We know what you’re thinking – What happens if the AP was to detect during normal operations that the channel you are using becomes in use by a proximal radar?

If this happens, then the AP may communicate to its Wi-Fi clients to stop transmitting on that particular channel. The AP will then switch to a different, available DFS channel within the Channel Move Time. This is usually about 10 seconds.

Unlike above, this could affect Wi-Fi clients. An AP won’t always announce that it is changing channels to connected devices. When it switches to the available channel, it will cause those Wi-Fi clients to disconnect from the network and then re-connect to the new channel.

 

Are DFS channels right for my Wi-Fi network?

If you are considering using DFS channels for your Wi-Fi, you need to think carefully about whether business critical operations rely on that connection. If the answer is yes, you might want to avoid enabling DFS and not risk the disconnections caused by DFS frequencies.

 

The Fundamentals of a Wireless LAN

We were going to call this blog ‘WLANs for Dummies’ but that seemed a bit harsh so we settled on the fundamentals of a wireless LAN instead.

A wireless LAN, or WLAN, might seem complicated on the surface but actually it really just follows simple laws of physics. If you can understand these and follow them, then there shouldn’t be any reason why you can’t achieve high performance and scalability for your WLAN.

If you can understand the basics of wireless physics, then you can start to plan your WLAN for a successful deployment. It will also help you to troubleshoot an existing WLAN exhibiting issues.

How Does Data Travel Through a WLAN?

First things first – Let’s look at wave properties.

Data transmits, or travels, from one point to another – e.g. between wireless access points – via electromagnetic waves. This energy travels at the speed of light and operate at different frequencies.

The frequencies of these electromagnetic waves are defined by how many periodic cycles are completed by second.

For example:

How is Frequency Measured?

As we said above, frequency is how many wave cycles are completed per second. This is measured in Hertz. A 2Hz waveform is 2 completed wave cycles in a period of 1 second.

How Does Frequency Affect a WLAN?

A phenomenon called Free Space Path Loss is something that causes signal loss when a waveform travels from one point to another. This is what affects how well data travels across a wireless network.

Different wavelengths (frequencies) experience difference signal loss. The lower the frequency, the longer the wavelength, and the longer the wavelength, the further it can travel before signal gets lost.

For example, 2.4GHz have longer wavelengths than higher frequencies like 5GHz.

How is Wi-Fi Signal Loss Measured?

We measure the energy that is associated with received wireless signals in Decibels (dB). We can also measure loss of signal in this way.

Decibels are logarithmic. On the linear domain, when you add decibels it grows exponentially and when you subtract decibels it reduces exponentially.

The 3dB rule

Every 3dB change, there is a doubling of energy (if increasing) or a halving of energy (if decreasing).

As a ratio, this would look like:

If we had the wireless signal energy at
1:10dB

Then doubling it would be
2:13dB

Remembering this rule can help with both analysing the energy associated with wireless signals as well as predicting it.
Similarly, if you add or subract 10dB, it changes by a factor of 10.

The Relationship Between Frequency and Wireless Signal

Let’s take a look at 2.4Ghz and 5GHz frequencies or waveforms. 5GHz is a higher frequency, so has more wavelengths in a given time period. 5GHz has more wireless signal loss (attenuation) than 2.4GHz, and thus is better for high-density areas. 2.4GHz has less wavelengths in a given time period and is better suited for wider coverage. Bear this in mind when you are planning or troubleshooting a wireless network.

How is Wireless Signal Affected by Different Materials?

In an ideal world, you would have a clear line of sight between your wireless points. In reality, this is rarely the case and you will often find things that get in the way and stop the wireless signal from traversing effectively across your network.

Different materials will affect wireless signals and attenuation in different ways.

Materials such as concrete will cause more attenuation of wireless signal than wood.

In scenarios where wireless signals can propagate (the action of spreading) normally, there is no interference from other materials. However, there are some things that can alter the propagation of a wireless signal, causing it to behave differently and potentially become unreliable.

For example, a WLAN environment with metal surfaces may encounter unpredictability with wireless signal due to it reflecting off the metal.
Wireless signal can also be absorbed by certain materials like water or people, causing the signal to falter.

Being mindful of materials during the WLAN planning stage can help ensure the environment doesn’t hinder your wireless network and you have reliable connectivity results.

Co-Channel Interference

Different materials aren’t the only thing that can interfer with wireless signals.

Due to the 2.4GHz and 5GHz frewuency bands being unlicensed, there are no restrictions on people when extending wireless networks with access points.

This means that they can become crowded as well as channels not being assigned efficiently. Both of these issues can cause co-channel interference.

When planning your WLAN it’s important to take these issues nito consideration and plan your wireless network accordingly so as not to risk problems with wireless signal later down the line.

You want your WLAN to be as effective and efficient as it can possible be, which takes planning and wireless network knowledge.

Whilst the 2.4GHz is popular due to its propagation qualities due its waveforms passing through materials like walls more easily and reaching end users at a long distance. This however has meant that its become crowded with competing devices such as cordless telephones, baby monitors and bluetooth devices. This saturation can cause problems with your wireless signal.

In comparison, the 5GHz spectrum has greater availability and relaxed transmission power giving it more flexibility when it comes to wireless networks.

The 2.4GHz band has only 3 channels without any overlap, whereas the 5GHz has 24. This is another reason why the 5GHz band is favoured for high-density WLAN environments.

Understanding Frequency Channels

To ensure you can maximise the performance and scalability of your WLAN, you need to understand how these channels operate and use that knowledge to avoid co-channel interference.

Let’s take an Access Point as an example. An AP will have a specific bandwidth through which it will transmit and receive signals to and from other points. The channel assigned to the AP will be appropriate for the centre frequency of the first 20MHz channel used by the AP.

This bandwidth is specifically the frequency range over which the data signals are transmitted. Peak transmission and power is spread over the range of that bandwidth, with it dropping off at the edges.

These edges are then at risk of meeting other nearby wireless networks and are prone to interference from the ‘noise’ of these other networks.

It’s important to use what you know about channels to prevent the reduction of wireless signal speed and loss of scalability of your wireless network.

In order to minimise interference between neighbouring access points, choose to assign them with non-adjacent channels. Following this will make it easier to scale your network. If you don’t follow this principle, you will likely encounter problems with latency and throughput.

The best way of reducing interference when assigning WLAN channels is to carry out a Wi-Fi site survey. This involves analysing the noise levels across the spectrum so you can make informed decisions for your wireless network.

Call The Experts

If this all sounds a bit complicated, then why not give us a call here at Geekabit? We have Wi-Fi expert engineers working out of Hampshire, Cardiff and London who can take care of all your Wi-Fi woes.

From Wi-Fi site surveys, to planning and installation, we’ve got your WLAN covered. GIve us a call or drop us an email to see how we can help keep you and your business connected.

4G Office Surveys – Hampshire, London and Wales

This week we spoke to a client needing a 4G office survey for their workplace, to see if 4G would be a viable internet option for their business, as well as identifying which network would be best for them.

Why would I want a 4G Office Survey?

4G broadband is an increasingly beneficial internet service provider for many homes and businesses, especially those in rural areas and places where BT Openreach cables can’t get to.

Here at Geekabit we take an unbiased approach when it comes to Mobile Network 4G surveys. Our aim is to gain an understanding of the mobile coverage on your premises and ascertain whether 4G broadband would be a good choice for your internet needs.

It is also hugely important for those who are considering moving their workforce to a new office building and need the guarantee of coverage. Even in today’s “Wi-Fi calling” world, we still need solid mobile phone coverage.

Our testing can assess any likely impacts on mobile network coverage in your office, from external factors such as wind farms and other tall buildings, to internal influences like wall composition.

What does a 4G Office Survey Involve?

Our equipment for a Mobile Phone Coverage Survey measures key performance indicators for 2G, 3G and 4G reception on various networks so you can be sure that 4G broadband is the right decision for your home or business.

The hardware we use to carry out in-building 4G office surveys uses advanced mobile network signal receiving and processing technology.

These 4G office surveys can be used to ascertain the internal mobile network coverage of your office or business premises, and identify any potential mobile network coverage problems early on before you commit to using 4G broadband for your internet provider.

There are some factors that could cause signal penetration problems (attenuation) such as different building materials and window glazing, but a 4G office survey can give you peace of mind that the 4G network you choose will be a reliable source of internet for your rural home or business.

Wired Certification through WiredScore

If you are a business landlord or even rent out a private property, carrying out a 4G survey for the premises can be extremely beneficial.

Back in 2015, the Greater London Authority launched a scheme through WiredScore – An initiative launched by the Mayor’s Digital Connectivity Rating Scheme.

This scheme gives a clear picture to tenants about the connectivity in their potential offices.

Over the past 18 months, we’ve all seen how imperative technology is – Where would we be without Zoom and Microsoft Teams? Technology plays a huge role in the success of businesses across the UK, not just London.

The capacity for connectivity in any given premises is an extraordinary marketing opportunity when it comes to landlords trying to get businesses to sign up to lease their office space. Commercial landlords and developers need to be aware of how important connectivity is to a property or premises – And a 4G office survey is a fantastic way to obtain this.

Good connectivity, especially when it comes to 4G in more rural areas, is a great asset to a business and will be top of the list of any business looking to secure new premises.

WiredScore provides the connectivity accreditation scheme to help overcome the challenge of proving your premises has the internet connection needed for a business to succeed. A WiredScore rating is a global rating scheme for digital connectivity and helps landlords to assess, improve and promote their premises.

Get in touch

If you’re struggling with wired broadband, and not getting the reliable internet connection you need in your rural business or home, then 4G could be a fantastic option for you.

It can feel like a big jump to give up on your wired broadband connection and opt for 4G – Which is where our Cell Coverage 4G survey comes in.

We can tell you exactly whether 4G broadband would work for you, and which network would be most reliable.

Relocating and moving offices comes with a raft of expense and issues which interrupts the daily workflow and output. Being confident that your team can communicate with your customers and stakeholders is a key consideration.

You can check out a previous blog of ours where we look at a few of our client case studies where 4G broadband was absolutely the best choice.

To see if 4G broadband would solve your Wi-Fi woes, get in touch with us today to arrange your mobile phone coverage survey. Let’s see if 4G broadband is the answer you’ve been searching for!

 

 

What is RF Design and Why Is It Important for my Wi-Fi Network?

Let’s face it – Our Wi-Fi expectations these days are pretty high. We want a strong, fast, reliable connection – And we want it all of the time. When we have good Wi-Fi, we barely notice it. But when it’s bad, it’s frustratingly apparent.

Unfortunately, what people don’t tend to realise is that a significant part of your wireless network is the RF environment. If you want your Wi-Fi network to perform to those high expectations, then you need to ensure you get this RF environment right.

Designing Your RF  Environment

It starts with the design. To create an effective RF design, you need to consider the environment that this Wi-Fi network is going to be functioning in. Are their neighbouring networks? What potential factors could cause interference?

You also need to consider how you need your Wi-Fi network to work. How many users are there? Will there be areas of higher density than others? These sorts of things define the requirements of the RF design. If you want good wireless network performance to meet those high expectations we mentioned above, then your RF environment needs to be correctly designed and managed.

The best way to identify what design would work well for your environment is to carry out a Wi-Fi survey. If you’re not confident in carrying this our yourself, then consider calling in the experts! We make it our business to provide comprehensive Wi-Fi surveys for any business or home environment. Our expert engineers can then design a Wi-Fi network tailored precisely to your needs, and then install it for you.

Analysing Your Wi-Fi Network

If your Wi-Fi network is already up and running, but you suspect there may be issues somewhere then network monitoring tools can be a useful way of providing visibility of any problems.

If you’re in the Wi-Fi field, then this will be a fairly straightforward exercise for you if you know the tools and how to use them. More often than not though, Wi-Fi network problems need a more in-depth analysis to really get to the bottom of what’s causing issues.

This again is where it might be best to call in the experts. Our Wi-Fi engineers have the specialist tools and knowledge to look at your Wi-Fi network, analyse traffic flow and examine exactly how data is passing through.

Are you experiencing poor wireless network performance?

It’s important to remember that you have very little to no control over what type of devices enter your network. Your Wi-Fi network may be open to guests or maybe even the general public depending on your business. Even non-Wi-Fi devices can have a significant impact on your wireless network.

Are you experiencing poor performance on your Wi-Fi network? To identify the problem you need to analyse 3 main components of your wireless network.

  • The configuration
  • The RF environment
  • The devices / users in your network

Luckily for you you’ve landed in the right place! Here at Geekabit, our engineers are Wi-Fi experts and can carry out Wi-Fi surveys, Wi-Fi Design and Wi-Fi Installation all from our bases in Hampshire, London and Cardiff. For more information get in touch with us today.

 

How Does Capacity and Coverage affect Wi-Fi Interference?

This week’s blog is the last in our series on Wi-Fi interference and what you can do about it. So far we’ve covered physical causes of Wi-Fi interference, how electrical devices can affect Wi-Fi through frequency interference and today we’re talking about capacity and coverage.

How does capacity affect Wi-Fi interference?

Capacity problems are most commonplace in corporate environments like offices. A potential issue that these environments might face is having too many users per broadcast device. This causes a capacity overload and that’s when you start to run into Wi-Fi problems.

Each Wi-Fi broadcast device, e.g. a router or access point, has a finite amount of bandwidth. This bandwidth is divided by the number of wireless devices connecting to it. So if only 10 devices are connected, then the bandwidth for that router will be divided by 10. It’s almost irrelevant how fast the internet connection is – If 50 people try to connect then the bandwidth is going to split 50 ways.

Ways to avoid issues with capacity and bandwidth, is to make sure that you don’t have just one router or access point serving an area of high density. If you have a lot of users or users with multiple devices in a certain area, then make sure you have the necessary number of broadcast devices. You might find our blog on ‘How Many Access Points do I need?’ helpful for this.

How does coverage affect Wi-Fi interference?

It’s not just about the capacity in an area, you also need to consider the distance that people are needing to connect across. Getting Wi-Fi coverage right is just as important as capacity.

We all know that that closer we are to a broadcasting device, the stronger and more reliable the signal is going to be. If you know that there will be users in a particular area of your office or business that will need to connect, then make sure that there is a device close-by enough to transmit a strong signal.

Coverage isn’t all about distance, it’s also about whether your devices are installed effectively. For example, it’s pointless installing an access point in close range to users if it’s pointing in the wrong direction, or hidden behind something. Wireless broadcast devices like routers or access points emit their signal in certain directions. Obviously you can’t see what way the radio signals are going so make sure that devices are installed properly. Access points that are hidden behind shelves, or wedged in ceiling tiles are not going to work the way they were intended to. Always check the instructions and manufacturers guide when installing any hardware so that they work effectively and reach the maximum coverage possible. If you’re not sure, then ask the experts!

What can we conclude on the types of Wi-Fi interference and their resolutions?

Wi-Fi has come a long way since it first arrived in our lives, and while the gap between wireless internet and wired is certainly closing, there’s always going to be some inferiority for Wi-Fi when comparing the two.

Some of the resolutions we’ve covered in this series of blogs on Wi-Fi Interference are:

  • Check for physical obstruction risks such as metal and concrete, and place your broadcast devices strateigically to mitigate risks.
  • Check your kit and upgrade where necessary. Devices that can use the 802.11ac frequency with dual band functionality are really useful for scenarious where you need to swap from 2.5Ghz to 5Ghz.
  • Always check for firmware upgrades. A bit like how you update the apps on your smartphones, manufacturers are constantly trying to better their performance by enhancing the software that runs them so do keep a watch for updates which are often free.

It’s so important to take careful consideration when designing your Wi-Fi network. If you don’t feel confident assessing your environment for the potential issues in this series of Wi-Fi interference blogs, then consider calling in the experts. Our Wi-Fi engineers can carry out a Wi-Fi survey followed by planning and design and finished with expert installation for effective and reliable Wi-Fi.

It’s Business As Usual for Geekabit

We’re still here, and we’re not going anywhere.

We are lucky that much of our work is done remotely. And for situations where this isn’t possible, we are fortunately able to continue working within the government guidelines.

As the nation once again faces a period of lockdown, we thought we would link some previous blogs that might prove useful in the coming weeks.

Whether you’re in work or find yourself working from home again, you might well encounter some Wi-Fi problems. Thankfully, many of them are pretty common and are relatively easy to fix. The below blog will give you some top tips to keep you connected.

Common Wi-Fi Problems and How to Fix Them

Got yourself such good Wi-Fi that your neighbour’s sneaking on? You need to make your connection more secure. Here’s how.

Who is Stealing my Wi-Fi and How Can I Block Them?

Desperate for a bit of time out of the house? Bet you never thought you’d be longing for the office! The weather might be turning a bit too chilly to be enjoying the sunshine mentioned in this next blog, but it could help get your Wi-Fi set up in the garden shed. Don’t forget your hot water bottle and flask of coffee!

How do I get Wi-Fi in my garden?

A reliable, fast connection is once again going to be the thing to keep us connected – To colleagues, friends and family. Don’t let rubbish Wi-Fi be the thing that isolates you.

As we said, we’re still here for all your Wi-Fi needs. Perhaps you’re thinking that a business empty of employees and customers is the best time to finally get your patchy Wi-Fi sorted. In which case, do give our Wi-Fi experts a call. Operating out of London, Cardiff and Hampshire, our engineers can provide a Wi-Fi site survey, plan and design your new Wi-Fi network and then install it for you.

Maybe your home Wi-Fi network isn’t cutting it for all your zoom calls? Over the past couple of months we’ve installed a number of 4G broadband kits in place of intermittent Wi-Fi, especially in more rural areas.

To discuss any of the above, please get in touch with us today.

Three types of Wi-Fi wireless network
There are three main types of wireless network – How do you know which wireless network is right for you?

Here we’re going to talk about three wireless networks to help you identify which would work best for your business.

We’ll be looking at centralised deployment, converged deployment and cloud-based deployment to see which one suits different types of applications.

Centralised Deployment

The most common wireless network system is centralised deployment. These lend themselves well to environments where buildings and networks are all in close proximity. This type of deployment brings the wireless network together which helps to facilitate advanced wireless functionality. It also enables easier upgrades. Wi-Fi controllers in these networks are based on-site, installed in a location at the centre of the network.

Converged Deployment

This type of wireless network works well for smaller environments such as an office building. They offer a consistency for both wireless and wired connections due to combining them both onto one network device. This device is an access switch which acts as both a switch as well as a wireless controller.

Cloud-Based Deployment

This deployment is ideal for networks that cover multiple locations. Devices connected on the premises of these different locations are managed by cloud software which via a dashboard, enables full visibility and management of said devices.

Once you’ve identified which network your business needs, you can then go about designing it. A site survey is invaluable at this stage, and enables a theoretical map to show up any potential problems before installation goes ahead.

If you need some assistance with your wireless network at any stage – From Wi-Fi site surveys, wireless network design, Wi-Fi installation or help with a current Wi-Fi network – Please don’t hesitate to get in touch with us today. Our expert Wi-Fi engineers are here to help, and are still working out of our Hampshire and London bases.