My colleague Kwame owns a laptop, a tablet, a smartphone, and a smartwatch; four personal devices (also called endpoints) that he will likely connect to any Wi-Fi network whenever possible.
Let us imagine a small organization of 10 users that are like Kwame. These 10 users are likely to connect 30-50 endpoints to the Wi-Fi network. Furthermore, let’s add all the additional devices that will join the network wirelessly due to our new technological advancements. Suddenly, our 10-user organization finds itself needing to provide permanent wireless connectivity to close to 100 endpoints with diverse power requirements which affect their ability to communicate on the network.
Another issue that faces wireless administrators is the increased adoption of real-time applications in augmented, mixed, and virtual reality where consistent Mbps+ speeds and low latency (for eg, <10ms) may be prerequisites for optimum functionality. We did not even speak about the new online gaming platforms that intends on streaming the games from cloud-based servers and transporting users’ game controller responses over the network while still providing a perfect reaction time (Google Stadia, Amazon Luna, etc.)
According to Gartner’s report, as of 2020 internet-connected devices across all technologies surpassed 20.6 billion (about 3 times the world population). The proliferated number of devices, connections, and bandwidth-hungry applications, entangled with a voracious requirement to reduce latency, has called for the evolution of Wi-Fi technology once again. Get ready, Wi-Fi 6 comes to save the day.
What is Wi-Fi 6?
The speedy wireless network that we know today and have come to trust so much that we even associate with the Internet connection, has gone through multiple iterations over the years. Improvements were made in power requirements, channel management, signal deconstruction and reconstruction, simultaneous streams, error detection and correction, encryption and security, and much more.
This brings us to today’s topic, the 802.11ax standard which is the 6th Generation, hence the term Wi-Fi 6. It is a simplified term coined by the Wi-Fi Alliance for easy understanding and reference of this complex standard. Wi-Fi 6 comes as a significant enhancement to the already great 802.11ac standard which was a big improvement to the older standards 802.11a/b/g/n that preceded it. Take a quick look at the evolution of the standards below and a key feature they improved on.
- Wi-Fi 6: 802.11ax (2019) – OFDMA
- Wi-Fi 5: 802.11ac (2014) – MIMO 4×4
- Wi-Fi 4: 802.11n (2009) – MIMO 2×2
- Wi-Fi 3: 802.11g (2003) – Dual band
- Wi-Fi 2: 802.11a (1999) – 5GHz Support
- Wi-Fi 1: 802.11b (1999) – 11 Mbps max data rate in 2.4GHz
- Legacy: 802.11 (1997) – Original IEEE WiFi standard
What is so special about it?
The air we use for wireless connectivity is subdivided into frequency bands called channels. Similar to your FM radio being able to pick up a radio signal to listen to voice and music, various ranges of the wireless spectrum are allocated to various technologies. In most countries, the Wi-Fi we know works at 2.4GHz and 5GHz. Those major frequency ranges are again subdivided into smaller chunks called a channel.
Look at each channel as a road and your data as the cars on that road. Each car gets onto the road and comes out before the one behind it. Right off, our friend Kwame has 4 cars on the road permanently. How bad is that? To improve traffic, we either have to reduce the size of the cars so more cars can pass on the same road at any given time (Compression, Multiplexing) or increase the size of the road by creating more lanes so that more cars can pass in parallel or allow bigger cars (Bigger Channel Size, MIMO). This is an oversimplification of the complex algorithms that make our Instagram feed load beautifully fast but am sure you get the point
Multi-User Multiple Input Multiple Output (MU-MIMO) was introduced as part of the 802.11ac (Wi-Fi 5) standard which allowed 80MHz (Channel Size) and even 160MHz transmissions and utilized 256 Quadrature Amplitude Modulation (QAM). Now, Wi-Fi 6 enabled access points with MU-MIMO can transmit as many as 8 data streams at once from separate antennas instead of four, leveraging a much higher 1024 QAM technology. The result of these improvements is a theoretical 9.6Gbps throughput per radio, up to four times more than 802.11ac. All of a sudden, the busiest road you take to work every day now has four times the amount of car lanes. That would be amazing, wouldn’t it?
Taking advantage of better and faster processing components and more efficient algorithms, Wi-Fi 6 utilizes the same airspace whilst granting us more speed and better latency.
NEW SCHEDULING METHOD
OFDMA (Orthogonal Frequency Division Multiple Access) leverages OFDM and makes the channel utilization dramatically better.
It works by dividing a wireless channel into smaller subcarriers and even further separating those subcarriers into smaller resource units (RUs). These chunks of bandwidth with varied sizes are then dedicated somewhat proportionally among multiple users simultaneously. Wastage is greatly reduced, and this makes OFDMA a very useful feature of Wi-Fi 6 within high-density areas.
Look at it this way. Not only do we multiply the number of lanes on that busy road by four, we also provide carpooling in every single vehicle.
IMPROVEMENTS IN IoT
IoT devices have a major constraint. They usually have a small battery that must last as long as possible. Wi-Fi technology is predominantly wasteful in terms of power. The challenge Wi-Fi 6 undertook was to provide a way for all IoT devices to communicate whilst expending the tiniest amount of energy.
Using OFDMA technology reduces transmission energy and a concept referred to as the Target Wake Time (TWT) was introduced. It facilitates stations or devices’ sleep periods up to 5-years without losing connectivity with their access points. Yes, you got it right. A device may remain connected for up to 5-years.
TWT coupled with Dual Subcarrier Modulation (DCM) allows IoT objects to send frames in redundant mode using more economical single modulation. Using this approach is cheaper and solves the IoT nightmare of retries. All these features make 802.11ax ready for high-density, real-time, and IoT environments. A wireless standard made to accommodate our increasing need to connect everything.
Wi-Fi 6E?… Wait! There is more?
Wi-Fi 6 Extended
Wi-Fi 6 has been around for a while now and technology only goes in one direction, the good one, the enhancement one, the Wi-Fi 6E one 😉
The 2.4GHz band is not unique to Wi-Fi and is usually prone to so much noise and interference. Not just that, there is a lot of contention in that space. That is why the Wi-Fi is always bad in those huge apartment buildings.
Wi-Fi 6E extends all the goodness of 802.11ax to the 6GHz band. As we keep demanding more connectivity, we are getting to the point where even the 5GHz band is getting choked since the spectrum within which it operates is very small.
With the Federal Communications Commission (FCC) opening up the 5.9GHz to 7.1GHz spectrum for unlicensed use, Wi-Fi now adds on a whooping 1200MHz range as opposed to the combined 400MHz used by the 2.4GHz and 5GHz, making room for all the perks of the 802.11ax standard to operate in a much larger spectrum.
It will definitely take time for routers and endpoints to catch up, but the future of Wi-Fi looks bright.
Wi-Fi 6 and Wi-Fi 6E bring a lot of excitement into our wireless networks, meeting the requirements of IoT devices, providing a faster, more efficient, more secured, and ultimately more resilient connectivity. Just as 5G promises smart cities and smart everything, 802.11ax technologies provide the counterpart in our homes and organizations.
Apotica deploys a large portfolio of Next-Generation and advanced technologies and is uniquely positioned to advise on the next steps to help with your wireless planning, design, and setup. You can request a free consultation here. To enquire about any equipment or software, call us on +233.54.431.5710 or write to firstname.lastname@example.org.