Wi-Fi Frequencies: An Overview

There are actually more Wi-Fi frequencies than you may think, and with all of the current and future Wi-Fi frequencies and technologies out there, things can get confusing. This blog will take a a high-level look at what’s out there and what’s coming up.

The Well-Known Frequencies — There are two dominant Wi-Fi frequencies used by 802.11a/b/g/n systems; 2.4 GHz and 5 GHz. Almost all modern Wi-Fi devices are made to operate in one or both of these frequencies.

Public Safety — The same basic OFDM technology used by 802.11a in 5 GHz is also used in a 4.9 GHz public safety band. This band is 50 MHz wide, is only available in some regulatory domains and requires a license. This band has specific, limited purposes, so you don’t see a lot of commercial interest or attention here.

802.11y — The FCC also opened up 50 MHz of bandwidth in a 3.6 GHz licensed band. OFDM is also used here. In the US, this band usage is not limited to certain technologies so the band will be shared, but does require a license. It seems that there aren’t many benefits to this frequency band, and the interference avoidance requirements represent a moderate R&D requirement without much ROI.

VHT <6 ghz=”” 802=”” 11ac=”” u=””> —  You may have heard about this PHY spec in development. It builds on 802.11n MIMO technology in 5 GHz and seeks to expand on the HT PHY with a few developments that are a natural next step. 802.11n gave us 40 MHz bonded channels. 802.11ac will give us 80 MHz channels and, likely, 160 MHz channels. 80 MHz bandwidth will get us past the gigabit rate threshold. MIMO will also be expanded to 8×8, but since client devices aren’t adopting that type of power hungry radio anytime in the near future (or ever), 8×8 will be used for MU-MIMO. MU-MIMO allows an AP to transmit simultaneous downlink frames to multiple users (MUs).

VHT 60 GHz (802.11ad) — This PHY opens up a fresh use case for Wi-Fi in the form of very high throughput at short range. At the 60 GHz frequency range, there are a lot of challenges getting the kind of range that would be useful to enterprises. We’ll see short-range, high bandwidth applications, but I’m still failing to see the exciting benefits that have been touted in the press.

White-Fi (802.11af) — There has also been some exciting buzz in the past several months about TV whitespace frequencies between 50 and 600 MHz. The benefits and limitations of this band are discussed in a number of good articles out there. Contiguous bandwidth is in short supply which is a big issue with this frequency, so we see a handful of 6 MHz-wide channels which will yield lower transmission rates than 802.11a/g. The merits of a low frequency are fairly well known; that is, despite the throughput-deficient bandwidth, the range/coverage is advantageous. The evident winner with this technology are rural broadband applications, where coverage is more important than bandwidth and high user density.

Least and last — 900 MHz. 900 MHz was a popular pre-802.11-Wi-Fi frequency way back in the 1990’s. It often gets lumped in with Wi-Fi frequencies because it is an unlicensed ISM band. You’ll still see some legacy technologies working their stuff there, and you might see a few modern, proprietary ones as well. This is a semi-popular broadband frequency with decent range and limited throughput. Many vendors use proprietary PtP and PtMP solutions here for wireless distribution, but they are not defined by 802.11, and they are not designed for client access. Shame on them.

Frequency Recap:

  • 50-600 MHz TV Whitespace — Good range, low capacity.
  • 900 MHz — Proprietary PtP and PtMP. Decent range, slow rates.
  • 2.4 GHz — Well-known and used.
  • 3.6 GHz — Little-used, licensed band.
  • 4.9 GHz — Licensed public safety band.
  • 5 GHz — Well-known and used, the future of Wi-Fi.
  • 60 GHz — Short range, very high throughput.

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https://www.cwnp.com/wi-fi-frequencies-an-overview/

Wi-Fi Frequencies: An Overview

With all of the current and future Wi-Fi frequencies and technologies are really getting confusing, with that in mind theres actually more than you realise. So let’s take a look at what’s out there and what’s coming up, as well as trying to make it as simple as we can.

There are two common well known dominant Wi-Fi frequencies used by 802.11a/b/g/n systems, 2.4 GHz and 5 GHz. Almost all modern Wi-Fi devices are made to operate in one or both of these frequencies. These frequencies now dominate most of our homes.

The same basic OFDM technology used by 802.11a in 5 GHz is also used in a 4.9 GHz public safety band. This band is 50 MHz wide it requires a license and is only available in some regulatory domains. There are specific and limited purposes for this band so you won’t see a lot of commercial interest or attention here.

The FCC also opened up 50 MHz of bandwidth in a 3.6 GHz licensed band. OFDM is used here as well. In the US this band requires a license but usage is not limited to certain technologies, so the band will be shared.  There aren’t many benefits to this frequency band and the interference avoidance requirements represent a moderate R&D requirement without much ROI.

You’ve most likely heard about this PHY spec in development. It builds on 802.11n MIMO technology in 5 GHz and seeks to expand on the HT PHY with a few developments that are a natural next step. 802.11n gave us 40 MHz bonded channels. 802.11ac will give us 80 MHz channels and, likely, 160 MHz channels.. 80 MHz bandwidth will get us past the gigabit rate threshold. MIMO will also be expanded to 8×8, but since client devices aren’t adopting that type of power hungry radio anytime in the near future (or ever), 8×8 will be used for MU-MIMO. MU-MIMO allows an AP to transmit simultaneous downlink frames to multiple users (MUs).

VHT 60 GHz (802.11ad) — This PHY opens up a fresh use case for Wi-Fi in the form of very high throughput at short range. There are a lot of challenges getting the kind of range that would be useful to enterprises. We’ll see short-range, high bandwidth applications, but there are still failings to see the exciting benefits that have been touted in the press.

White-Fi (802.11af) — The TV whitespace frequencies between 50 and 600 MHz have also created some exciting buzz in the past several months. There are many articles out there discussing the limitations and benefits of this band. The main issue with this frequency is that contiguous bandwidth is in short supply, so we see a handful of 6 MHz-wide channels, which will yield lower transmission rates than 802.11a/g. The merits of a low frequency are fairly well known; that is, despite the throughput-deficient bandwidth, the range and coverage is advantageous. Rural broadband applications are the evident winner with this technology where coverage is more important than bandwidth and high user density.

It is also worth mentioning 900 MHz. Back in the 1990s, 900 MHz was a popular pre-802.11-Wi-Fi frequency. It is an unlicensed ISM band. This is a semi-popular broadband frequency with decent range and limited throughput. Many vendors use proprietary PtP and PtMP solutions here for wireless distribution, but they are not defined by 802.11 and they are not designed for client access.

Wi-FI frequencies in brief:

  • 50-600 MHz TV Whitespace — Good range, low capacity.
  • 900 MHz — Proprietary PtP and PtMP. Decent range, slow rates.
  • 2.4 GHz — Well-known and used.
  • 3.6 GHz — Little-used, licensed band.
  • 4.9 GHz — Licensed public safety band.
  • 5 GHz — Well-known and used, the future of Wi-Fi.
  • 60 GHz — Short range, very high throughput.
WLAN vs WI-FI

Image result for wlan vs wifiThe ease and convenience are the main factors in improving data communications. Whenever possible the main goal is wanting the least amount of affect in connecting yourself to others. Todays current technological advancements are enabling more of us to transmit and receive information without the hinderance of physical connections. Certainly, for network administrators and engineers, nothing presents more ease and comfort than the wireless means of connecting devices.

WLAN, short for Wireless Local Area Network and sometimes called Wireless LAN, is a network of computers over distances of a few hundred feet that uses high frequency radio signals to transmit and receive data. The network can also connect multiple computers to a central information system, a printer, or a scanner. This provides mobility in networking  and therefore frees us from the awkwardness of relying on cables for connectivity. 

Simply put, WLAN allows peer-to-peer data communications and/or point-to-point within a relatively small area, a building or campus setting for example. Conventional LANs typically use twisted pair, coaxial wires or in some cases optical fibres. WLAN removes these physical connections and uses electromagnetic wave signals instead to transmit and receive data within the network. Potentially the transmission is not as fast as the one provided by a conventional LAN however for most users, average and industry professionals alike, the slower transfer rate is a minor limitation and does not pose a problem.

WI-FI means Wireless Fidelity. The term is actually a trademark name used to brand products that belong to a category of WLAN devices. The devices or hardware branded with the WI-FI trademark is based on the standards stated by IEEE 802.11. In most cases, WI-FI is considered by the majority as synonymous to the actual standard itself.

An association of companies all around the globe called “The WI-FI Alliance” endorses WLAN technology and the products involved with it. This alliance also certifies various hardware and devices if they measure up to the standards of interoperability. It should be mentioned that there are numerous devices that indeed conform to the standards but are not certified by the WI-FI Alliance and therefore, do not sport the WI-FI logo. The reason for this is the cost and hassle of the certification procedure.

A WI-FI (ready) device effectively means that it is ready for use in a WLAN. Such devices range from desktop computers, laptops, notebooks, to smartphones, palm tops, and other small devices.

 

Siklu EtherHaul-2X00 Series

1 Gbps connectivity between two sites is sometimes necessary and an E-band set of radios that work within a 70-80 Ghz frequency is a viable solution.  The benefits of these radios are vast and varied.  Being relatively cheap makes them popular and this coupled with the fact that they are easy to deploy and manage makes them a Wi-Fi winner.

Siklu have created a solution in an E-band set of radios that will provide 2 Gbps connectivity over up to 7kms.  This wider channel width solution is able to work at lower modulations which makes it a great option compared to others on the market.  The EH -2X00 delivers 2Gbps full duplex point to point wireless connectivity making it robust and futureproof.

Being small in size, the tiny footprint allows easy site acquisition and an easy installation.  Moreover, the E-band spectrum is uncongested and offers a quick licensing process compared to other options.  Spectrum protection is maintained whist the cost is still relatively cheap.

The EH-2X00 series offers a great price per MB but alongside this its lower installation costs make it unbeatable in price.  The new model is based on an evolved version of a Siklu’s field proven platform making it extremely reliable.  This reliability cuts the cost of site visits which contributes to its exceptional value for money.

With 16 non-overlapping channels available to it, the EH-2X00 is able to deploy dense networks over greater distances and offers a great solution for those looking for 1Gbps between 2 sites.

Coffee shop cyber-security – how high is the risk?

It’s fair to say that the media has a way of taking an idea and running with it, which can often create hysteria.  This week we’ve been reading a lot of stories about internet security in public spaces and have been questioning the findings.

 

Ipass have just published their 2017 security report and the findings have been interesting.  Coffee shops have been flagged up as public networks where hackers can most easily access other people’s data.  The findings stated that CEO’s present the greatest security risk to businesses as they are often working remotely and therefore connect to public wi-fi which could pose a risk.  Of course, CEO’s are in possession of valuable information and so the risk to a business could be colossal. Interestingly, the report states that many organisations have stepped up their security measures and don’t allow employees to connect to public networks due to concerns about internet safety.

 

These findings have not only raised questions for businesses but have also raised questions about our everyday safety and how reliable public wi-fi really is.  However, there are ways to ensure that you are always secure.  VPN’s can help to create a safer connection by encrypting information travelling to and from a device.  Using a VPN can inhibit these attacks and keep your information safe so we thoroughly recommend looking into that as an option.  The reports are interesting and raise valid points about cyber security.  However, it’s always worth bearing in mind that there are ways to reduce your risk.  Get in touch to find out more!

 

Read the full report here:

https://www.ipass.com/wp-content/uploads/2017/05/iPass-2017-Mobile-Security-Report.pdf

Battle of the best connection

This week, our interest in maintaining incredible internet connection has lead us to finding out which countries Wi-Fi is performing best.

 

And the results have been interesting…

 

Rotten Wi-Fi’s latest findings show that the UK is surprisingly quite far behind other countries in terms of interest speed.  Public Wi-Fi has become a pretty essential part of everyday life for most of us and the demand has certainly increased in recent years.  Interestingly the UK falls behind countries such as Lithuania and Switzerland when comparing the average download speed.

 

Although we do come in behind Lithuania, Singapore, Denmark and Switzerland in terms of internet speed, we are placed ahead of the USA and Germany.  In fact, the USA and Germany haven’t been doing so well in recent years and their internet speed hasn’t made the top 20 until this year.  The latest findings show that countries such as Latvia, Hungary and Estonia are still ahead of Germany and the USA in terms of download speed.

 

Lithuania tops the charts with the fastest public Wi-Fi, followed closely by Denmark.  Fast and effective public Wi-Fi is hugely important in the modern day and we’ll be interested to see if the UK can develop their Wi-Fi speed to keep up with the demand in the coming years.
Data source: www.rottenwifi.com; November 2016

Image Credit: Alto Digital

Dreaded Dead Spots

We’ve all been there.

 

You’ve set out to do some work in a coffee shop and after ordering your coffee and finding the perfect corner to settle down in you realise the Wi-Fi doesn’t work there.  ‘Typical’ you think as you pace around with your device in hand trying to find a connection.

 

This week we’re trying to discover what it means to have a Wi-Fi dead spot and how to avoid these cursed spaces.  

 

There can be so many reasons for these dead spots but the main ones are building interferences ie – thick walls or awkwardly placed Wi-Fi access points that can’t reach certain areas.  With that in mind, it can be quite easy to fix these mysterious dead spots which makes it all the more frustrating when you come across one.

 

If you find a dead spot in your home or business space the first thing you can do to try and close up these dead spots is to re-position your access point.  Often central locations suit access points best, where they can get away from thick walls or fire exits which can all interfere with signal.   

 

That brings us to our second suggestion – removing obstructions and ensuring that your access point is free of any interference.  Often clients don’t realise how easy it can be to eliminate these obstructions from the area.  If you identify anything near the access point that you think could be causing problems then remove it and see if the dead spot remains – in most cases dead spots require a trial and error approach. Other electronic devices and thick metals can be a source of interference that often go overlooked but it’s worth getting to the bottom of the issue and ensuring that you try removing as many obstructions as possible to see if that affects the dead spot.
If you need more advice on how to avoid these frustrating dead spots then don’t hesitate to get in touch.  It’s always helpful to get an expert opinion if the problem persists.

Wearables wreaking havoc

This week at Geekabit we’re talking about wearables.

Wearables are the newest fitness craze and it seems that social media is full of people uploading their data.  Everyone is tracking their heartrate and their steps these days and we’re not complaining.  Wearables are a great advance in technology that can benefit health so we’re all for the latest craze.

However, we are not for the congestion that has inevitably increased since wearables became a ‘thing’.  Wearables are often Wi-Fi enabled, however ones that aren’t can really cause problems since the Bluetooth that they operate off of uses the same 2.4Ghz frequency as most Wi-Fi services.

The initial cause of disruption is just the fact that people have gone from having one device to having two or three which puts pressure on the network.  Not only that but as we previously mentioned, there is the danger that your 2.4Ghz band will get congested by wearables operating using Bluetooth.  As people become more and more attached to their wearables and start to take their data seriously, it is becoming hugely important to have a Wi-Fi service that can handle the demand.

Luckily we know a few tricks that can help solve these issues and make sure that your customers don’t get frustrated by the congested W-Fi.  An easy way to solve the congestion is ensure that fewer devices are operating on the network, as every device is using up bandwidth.   It might pay to get a separate network for personal use or for employees if your network is based in a place that is used by both customers and employees.  As always with these things, a survey is a great idea.  A Wi-Fi survey will tell you exactly what is going on with your network and how much it can take vs what pressure is being put on it.  This is hugely helpful to any business experiencing Wi-Fi problems which have potentially come about by increased pressure on the network from wearables.

If you think that your network is being affected by  wearables then don’t hesitate to contact us to gain some useful advice on how to solve these issues.

Hotel Wi-Fi: Why doesn’t it work?


We have all experienced the frustrations of hotel Wi-Fi.  It seems that despite hotel Wi-Fi being an essential these days, it’s rare that hotel networks actually work efficiently.

 

Incorrect channel plans are the main source of interruption and in some ways the easiest to control.  In most cases channels 1, 6 and 11 are appropriate channel plans and work well in most countries.  Difficulties arise when hotels have each adjacent AP connected to the next available channel.  This causes adjacent channel interference whereby your device connects from channel 1 to 2 to 3 and so on as you move around the space.  As previously mentioned, channels 1, 6 and 11 work well in most countries and using these channels appropriately can significantly improve your network.

 

The other common error is trying to connect to 2.4GHz instead of 5GHz.  As we’ve discussed in previous blogs 5GHz is the more appropriate bandwidth in most cases, yet hotels still connect to 2.4GHz, which as we know is overcrowded and somewhat of a junk space.  Turning off 2.4GHz will help to reduce this interference.

 

Access point placement is also crucial to hotel networks and can sometimes be the downfall.  Client devices need to be in clear range of the AP without things like smoke detectors, exit signs or thick walls getting in the way.  Again, this is easily solved by finding the areas where signal is experiencing interference and relocating the AP’s to more appropriate areas.  Often hotels can try to do the job cheaply and thereby place AP’s in convenient places which turn out to be rather ineffective.  


Those top three hotel Wi-Fi fail are the reason for lots of customer frustration and complaining which could be easily avoided.  If you, or a business you know needs help with hotel Wi-Fi then be sure to put them in touch!

Wi-Fight against external antennas?

Internal antennas are used for ordinary access points and the chances are you are no stranger to those.  However, most people haven’t considered external antennas for fear that they will be too costly and time-consuming to set up.  Often people are unaware of the benefits of external antennas so this week we’ve been looking at the advantages and disadvantages of external antennas and have found some interesting info.  External antennas are great for use outdoors and can have a huge impact on the overall network performance by increasing directional accuracy.

Firstly, let’s brush up on what types of external antennas are out there.  Omni-directional antennas are useful for outdoor spaces that are large in size and cater to big numbers.  However, semi-directional antennas do exactly what you would imagine.  They direct the network to different areas and range in degrees which mean they can cover a specific area.  The downside of semi-directional antennas is that they are not so great for large areas since they are highly focused and often come out of something like a dish.  They have a very small range but can be powerful.

An Azimith antenna pattern is what you can expect to use with an external antenna.  Understanding this alongside knowing how the WiFi signal moves around the space you are working with and being able to mentally visualise it will hugely help in the deployment of the outdoor antenna.  It is essential to mount the antennas properly and take the time to get the right angle.  It’s also crucial to consider the spacing between antennas to avoid connecting two antennas to one access point.  The exception to this rule is if you are using a DART connector which can handle it but for the average external antenna avoid this at all costs.

Wi-fight against external antennas? Hopefully this blog post has given you a bit of insight into external antennas so you can learn to love them like we do!