Mar 10 2012

Demysti-Fi Wi-Fi

 

Wi-Fi has been one of those conveniences that has been around for a little while now but with an increasing number of Wi-Fi standards you could be forgiven for not understanding some of the key differences (including speed and connection requirements) between them all.

Currently, we have four Wi-Fi standards with another one on the way:

  • 802.11a,
  • 802.11b,
  • 802.11g,
  • 802.11n,
  • 802.11ac (under development).

The standards with which most people will be most familiar are the 11b, 11g and 11n variants with the 11n variant probably causing the post confusion for most.

But what do those letters and numbers actually mean for users?

Well, it basically boils down to a few key areas:

  • Speed,
  • Wireless frequency (the radio band used for the connection),
  • Minimum security to obtain the maximum possible hardware speed.

To keep things simple, I’ve knocked up a table to make it easier to compare all of the standards:

Wireless Protocol Speed Wireless Frequency Minimum Security for Max Speed
802.11a 54 Mbps 5 GHz None, WEP
802.11b 11 Mbps 2.4 GHz None, WEP
802.11g 54 Mbps 2.4 GHz None, WEP, WPA+TKIP, WPA2+AES
802.11n 54 – 600 Mbps 2.4 GHz / 5 GHz WPA2+AES
802.11ac 433 – 6930 Mbps 5 GHz TBA

So what do you need to know about the above Wi-Fi standards?

Firstly, let’s look at the aspect of speed. As you can see, 802.11b is the slowest of the bunch but these days you won’t find too many of these networks around given the affordability and availability of 802.11g and 802.11n gear. More commonly, you’ll find 802.11g networks running at 54Mbps in public areas while 802.11n networks are beginning to be found more often in households and some businesses running from anywhere from 54Mbps to 600Mbps.

A question you might ask at this point is why do 802.11n networks vary in speed so much?

The simplified answers are:

  1. encryption protocols being used (if you don’t use WPA2 + AES then speeds are throttled back to 54Mbps),
  2. limited antennae in the access point or the interfacing device (more antennae mean more pipes for data),
  3. neighbouring legacy networks (802.11a, b or g) using overlapping channels (802.11n networks use a wider range of frequencies to gain higher speeds).
Granted I have spared a deal of the technical details (which I’ll look at fleshing out a bit more in a future post) but at a high level those are the main causes of speed variation and limitation when using 802.11n networks.
So what about the different frequencies?
Firstly, 2.4GHz was favoured by manufacturers as the band of spectrum at this frequency was unlicensed (i.e. they did not have to purchase carrier licenses in various countries to ensure that the spectrum was available for usage). However, the downside of this is that a range of other devices also use the same narrow band of spectrum including cordless phones which means that network performance may be impacted due to interference. The band of spectrum can differ between countries (which is why you might see greater or fewer channels on your wireless router compared to those from other countries). Another benefit of 2.4GHz spectrum is its broadcast range given its lower attenuation (that’s a fancy term for “fading out”) and ability to still somewhat survive after passing through some solid objects.
5GHz on the other hand is seen as uncrowded spectrum with 23 available channels compared to 11 channels in the 2.4GHz band. The ability to combine neighbouring bands to increase throughput it also a lot easier compared to 2.4GHz networks “dual channel” networks which will fall back to single channel mode if a nearby network is also using one of the utilised channels. However, the drawback with 5GHz networks is that the signal fades out more quickly compared to 2.4GHz networks unless you increase the broadcast power but unfortunately the broadcast power can be limited in certain countries which ends up restricting the effective range of a 5GHz network. Furthermore, boosting the signal would require more expensive components in a wireless device to reliably maintain such an output while impacts to battery life for mobile and portable devices would also have to be considered.

Finally, what does security have to do with getting the fastest speed?

It should go without saying that you should use the highest possible security available on your wireless router. I have written before about how WEP should not be used at all as it offers negligible security over an open Wi-Fi network and WPA2 should always be the first choice, if possible. That said, on 802.11n networks the use of WPA2 with AES (as the encryption protocol) is absolutely required to achieve connection speeds greater than 54Mbps (click the link to read more). Don’t short change yourself twice by running at a lower level of security and not getting the full speed from your network connection.

Anyway, hopefully this has clarified the current state of Wi-Fi networks for you. If you have any questions then drop me a comment and I’ll try and answer them as best as I can.

Boydo

My name is Boyd and I’m a Service Management Specialist with a knack for operational data gathering, transformation, analysis and reporting.

In 2012, I obtained my Masters of Science in Information Technology through the University of New South Wales @ The Australia Defence Force Academy (UNSW@ADFA).

I was also part of an online community known as the Panasonic Insider Crew in the capacity of “Insider Guru” for Panasonic Australia where I interacted with other tech enthusiasts and find out more about Panasonic's latest gadgets.

I love technology, gadgets, and the Internet and maintain a keen interest in these areas locally, nationally, and globally. I hope by sharing my views on these topics that people will receive an honest point of view from someone with a genuine interest in these topics.

I have also written and edited articles for Neowin - you can check out my articles over @ https://www.neowin.net/news/poster/boyd_chan

I hope you enjoy reading my blog!

2 comments

    • William (Bill) Yeager on March 11, 2012 at 00:48
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    • Reply

    Wow Boydo, thanks for this detailed explanation!
    The wifi world and its gadgets have always mystiFI-ed me but this blog entry of yours makes it easier to understand the various acronyms and the implications on efficiency and usage.
    A well very crafted article on a relevant topic… Keep it up!
    I look forward to more analysis and information which usually is available on your blog.
    Hope you do not mind, it took the liberty of using a pseudonym.

    • SM on March 11, 2012 at 00:53
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    • Reply

    Thanks Boyd! Appreciate your input on the various aspects and innards of the common home router. Its amazing the layers of technology that go into making home wifi possible. Thanks to you after reading this article, I will be able to find my way around the alphabets (n,g,b,c,a) … or should I call them letters?
    Looking forward to more of your tips on speed, security and home gadgets.

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