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.

A Guide to Wi-Fi Requirements.

Do you know what you want, what you really, really want?

Sometimes we need to flesh out real requirements for a Wi-Fi service.  A common request from customers is simply, “Install Wi-Fi at xyz location”.  Actual requirements start with understanding the desired outcome or performance expectations and working backwards from there.

There are relevant questions.  Such as what type of user experience is required and what density of users will be simultaneously using the Wi-Fi service. Or what existing systems does the service need to integrate with?

Business questions first.  If we don’t understand the business reasons for wireless in the first place, we won’t be able to design a solution that meets expectations.  Why is the business investing in a wireless service, what are the required business outcomes and timelines and how will the business measure the success of the installation?  What applications will they run and what type of activities do the business expect users to perform over the wireless medium?

Technical questions that address wireless functionality naturally follow. The customer may have standards that must be followed to integrate a wireless service:  user authentication, encryption, device management, reporting, logging, wireless intrusion detection (and desired responses), application performance, density of users, or different user groups.

From answers to these business and technical questions, we are able to begin noting the Wi-Fi requirements.  The discovery phase will assist here:  identifying supporting infrastructure, is there adequate bandwidth for the solution, is Quality of Service (QoS) required for application performance and which 802.11 standards need to be supported.

During the process of discovery, in some situations we may find that a Wi-Fi solution will not actually be fit for purpose!

The physical environment where wireless service will be installed prompts its own questions.  If site access for an inspection is difficult: a picture tells a thousand words.  A few well-chosen photos of the wireless environment will tell us a lot about what needs further analysis.  The environment will mandate if internal or external (weatherproof) Wi-Fi equipment is necessary, if internal or external antennas will be required, where there may be coverage challenges and so forth.  Physical security of equipment inside the environment should also be taken into consideration.

Site surveys are crucial.  We will want to know if the proposed environment is subject to wireless interference or,  if it has to contend with 50 foreign Wi-Fi networks fighting for the same channel space.  Site surveys can discover useful information that then become technical requirements that feed into the design.  For example, if a site survey uncovers heavy amounts of interference on a commonly used channel by Wi-Fi, then the design can avoid using this channel.

Most importantly: with Wi-Fi it is all about the client.  If the technology the client is using to connect to the wireless infrastructure is poor, then the experience will be poor.  No matter how good the wireless system.  If you have a mixed bag of client devices, old and new, fast and slow; all of this will affect the design.

So tell us what you want.  What you really, really want.