How to get 1.3Gbps throughput over WiFi

Most manufacturers advertise impressive speeds of up to 1.3Gbps (Gigabits per second) for their latest WiFi gear.  That’s pretty quick.

However, WiFi is a half-duplex technology that relies on substantial protocol overhead to transmit and receive. 1,300Mbps is actually only roughly 650Mbps in the equivalent wired domain, the domain that we are used to comparing speed and throughput.  Also, that target of 1300Mbps will not have a sustained throughput rate like a wired connection, it will be decidedly ‘spotty’.

That said, to get 1.3Gbps [half-duplex] throughput on your WiFi, start with a high performance enterprise-grade wireless Access Point (AP) and a modern high performance laptop i.e. minimum of 3x antennas built-in.

Next, we need to remove everybody else’s devices.  Turn off EVERY other WiFi capable device within 100 metres.  This includes all devices outside of your control.  Neighbouring WiFi modems and wireless Access Points, all other laptops, tablets, smartphones, SmartTVs, Chromecast, Apple iSomething, microwave ovens, IoT emitters, baby monitors and so forth.  Nothing else should be left on.

By now, we must be in a cave somewhere.

Next: tune the specific enterprise-grade features on the AP for high-performance.  Left at default parameters out of the box, key settings critical to high performance would not be enabled.

Then (very important): place laptop within 3 metres (10 feet) of the AP.

Alternatively: go to a specialised wireless testing facility where just you and your laptop sit in a special little room that repels all wireless interference (roughly akin to a recording studio with soundproof walls).

Either way, this is the only way that we will come even close to the advertised speed.

Back to the real world.  Undoubtedly, from time to time your laptop may be in an insanely good position relative to the AP and environment and advise that your connected data rate is indeed 1300Mbps.  In the wired world, this would actually be what you are getting.  In the wireless world, this is not what you get.  You get (substantially) less.

Consider the wireless data rate to be similar to the maximum speed on a car’s speedometer.  Your actual speed, will be limited by the traffic and environment around you.  Just like wireless.

802.11ac – Is it worth the investment? Part 1 of 2.

Why would you invest in 802.11ac technology?

It’s a good question, and a common one.  For most businesses to invest in 11ac (IEEE 802.11ac), the business value of the technology needs to be measured.  This can be hard.  To assist us, it is worthwhile to set a baseline. Before we look at that however, just what is 802.11ac?

In a nutshell, it is the latest technology advancement in the IEEE standard for Wi-Fi performance or speed. Before this, there was [IEEE 802.11] a,b,g and n.  Each amendment progressively supplies faster, more efficient service to Wi-Fi clients and consequently better performance for all over a wireless medium.  From a business standpoint, you may ask how faster Wi-Fi helps your productivity?  I will attempt to answer that below.

Back to the baseline.  The baseline can be measured in two parts.

  • First, we can look at which stage of evolution your business Wi-Fi is at.
  • Second, we note which benefits 11ac can bring to an organisation’s network and what it promises in the future.

With the first part, your business may be one of three places right now:

  1. There is no existing wireless solution but there is a new business need that requires it.
  2. The business has an existing Wi-Fi installation that is over three years old and due for an upgrade. Or it is opening a new site with no Wi-Fi and is considering deploying the latest Wireless Access Points there.
  3. The business needs cutting edge technology.  It has a relatively recent installation of 802.11n and is looking to take advantage of the latest Wi-Fi enhancements in 11ac.

The second part of the baseline is understanding that 11ac technology is essentially coming in two waves.  Wave 1, the 11ac that we can buy today, provides at least a 30% speed increase over 802.11n, sometimes even 150% – but this comes with lots of caveats – more on that later. Wave 2, where the promise of the real spectacular is (at least to Wi-Fi professionals like myself), are anticipated to be released by some enterprise wireless manufacturers sometime in 2015.

Why is the speed increase important?  More throughput usually equals higher productivity.  Users can do their work faster if they are not waiting to “use” the network.  Unlike the dedicated network cable connected to your laptop with all that bandwidth just for you, wireless is a shared medium; where only one device can talk at one time and where all devices connected to the same Wi-Fi Access Point queue up, to send and receive traffic on it.  The speed increase means that devices with faster technology use the shared medium for less time to send the same amount of data.  Basically, you’re on and off faster which means a quicker performance for everyone.

So faster speed = better productivity.  But to a business, it must examine the material benefit: if my Wi-Fi transfers data say, 50% faster than before, does that provide any real value?  If I sit at my desk sending emails, preparing documents and browsing the web, is this network performance increase going to equate to markedly improved productivity on my part?  Perhaps not.  If the Wi-Fi is doing a lot of file transfers, video/voice or other downloads, then yes. I believe it is something that only each organisation can calculate for themselves.

It all ties back to the “Should I invest” question: the answer is entirely dependent upon where your business is at in the adoption of wireless.  I will talk about this in Part 2.