Category:WiFi Challenges and Limitations

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Wireless networking is one of the most useful of all modern technologies, allowing levels of convenience and flexibility that would have seemed like science fiction only a couple of decades ago. But, it can sometimes be problematic. In this guide, we cover some of the common problems that WiFi users experience, together with measures that can be taken to mitigate them where this is possible.

Ask yourself: "Could I use a network cable instead?"

"Could I use a network cable instead?"


If WiFi is being problematic, always examine whether or not an ethernet cable could be used instead. Wired connectivity is always going to be more reliable, and faster, than wireless connectivity. It may sound like a defeatist suggestion, but where reliability and maximum performance are required, a cable is always the best method of delivery.


Running cables to every place in every room will often be impractical, and in the case of some portable devices (lacking the relevant network socket), actually impossible.


But every device moved onto a cabled connection (and having had its wireless interface properly shut down) is one less device tying up the wireless channel. So moving all the devices that you possibly can onto wired connections may actually benefit all those left on WiFi.


This may not be as daunting as it sounds - you do not need to run a separate cable from every device back to a central point (structured cabling). High speed (gigabit) switches are surprisingly cheap, and can even be powered over the Ethernet cable, so getting one cable behind the TV could easily power a switch with 4 ports that connect to TV, Sky box, Apple TV, and so on without even needing an extra power socket. Our support staff will be happy to explain options with switches and cables if you need.





The fabric of the building

The methods employed in the construction of your property will impact the usability of WiFi, and not always in the ways one might expect. There are not general rules of thumb about the age of the property. It is impossible to simply say "older buildings are worse for wifi", for example.


Buildings with brick, concrete or stone walls usually have problems with wifi signal between rooms. That is to say, a laptop being used in one room, with the access point in another room, is likely to have a lower than ideal signal level. But, on the other hand, the attenuation of the outside walls helps reduce stray signals from neighbouring networks.


Buildings with timber/drywall stud walls often make WiFi connectivity between rooms easier, unless any 'foil backed' drywall has been used, which always makes matters far worse.

2.4GHz -vs- 5GHz WiFi

Conventional wisdom often suggests that a switch from 2.4GHz WiFi over to 5GHz will immediately yield improved performance. This is often absolutely true. But it is important to explain the difference between the two, and where 2.4GHz might actually be better.


2.4GHz is the original standard for WiFi. As a result of this, far more devices in the world today support it. The consequence of this is that the 2.4GHz band is very much more congested with traffic. The more devices sharing a finite number of channels, the more likely it is that there will be collisions and retries when devices transmit, diminishing the performance and reliability for everybody.


In high-density residential developments 2.4GHz is often completely unusable nowadays for this reason.


5GHz is a much later standard, and as a result fewer devices support it. This means that 5GHz is a less congested band.

The Laws of Physics

There are some aspects of physics that can come into play as well. 2.4GHz will tend to travel through solid objects (like brick and concrete walls) somewhat better than 5GHz. Inside of an individual property, this may actually be an advantage, since the 2.4GHz signal from an access point to a device will be stronger. On the other hand, the outside walls of the building will tend to let in more stray signals from neighbouring networks.


With 5GHz, unwanted signals coming in from outside will be much more highly attenuated, but also, signals from one room to another internally will be weaker.


Usually, nowadays, 5GHz proves better over all. But not always.


On a very remote rural property, far away from any neighbours with potentially interference-causing networks, but with very thick flint walls, it is quite possible 2.4GHz will actually work better than 5GHz. In urban premises, such as modern blocks of flats, 5GHz is almost always preferable due to the 'light density' construction techniques (studs and drywall) but the high number of neighbours all in a small area.


Just to add to the confusion there is a new WiFi standard that can use multiple frequencies together, called WiFi6. It may be a few years before this is a sensible choice, and at present the equipment for this is very expensive. In the long term the WiFi standards are always improving and could make WiFi in the home simpler and better.

No guarantees - but we'll always try our best to help you

The service we sell is "Internet Access", and we work hard to ensure the performance of that service is the best it can be. But that is a service up to the broadband router. WiFi is down to the equipment you connect to your Internet service.


The routers we sell have WiFi to a specific standard for the power and signals used. Ultimately, we can never guarantee that a particular router with built-in WiFi will be able to cover a given property due to the numerous reasons given in the paragraphs above.


We can also never guarantee that a WiFi network will continue to work indefinitely. We have experienced situations where the RF environment around a customer's property has changed (for example, an increase in the number of neighbours running WiFi networks, causing more congestion on the channels). Obviously a neighbour's activities are entirely outside of our control. We can usually improve matters by doing a site survey, and looking for a quieter channel on which to place our customer's WiFi. But, again, this is not always possible.

More advanced access points, more of them, and sensible locations

The inbuilt access point in most broadband routers will almost never be as good as a dedicated access point, or, even better, multiple access points covering a property. If it's possible to do so, installing access points on each floor of the property, or in each area (or even room), properly configured, will give the best chance of good WiFi performance throughout.


Some dedicated separate access points employ clever tricks to improve signal delivery to devices, such as 'beam forming', where arrays of antennas inside the unit actively direct the signal towards the device it is intended for. This can reduce interference to and from other devices. Some access points automatically adjust their power level to reduce interference. It may seem counter intuitive that a lower power level may improve, but if fewer people in a crowd are shouting, each individual stands more of a chance of being heard.


The location of access points can impact how well they work too. Ideally they should be located away from other objects (especially metal objects). In situations with small number of access points (or indeed just one) it is preferable to choose a location close to the centre of the property to be covered.


Our support staff can offer advice on multiple access point solutions - they can be quite expensive for the next WiFi.


Our director has a blog post on the matter of WiFi in an old Welsh school house: Here.

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