22 years ago (in 1997) the first base IEEE 802.11 standard (currently known as “WiFi”) was released to the world.
Since then, the standard has gone through a number of developments and enhancements to cover the needs of users who are hungry for fast wireless connectivity (in home networks, offices, workplaces, public areas etc).
Table of Contents
Brief History and Overview of 802.11 Standards
It’s important to note that the official IEEE standard for wireless Local Area Network (LAN) communication is known as 802.11 with various sub-naming designations such as 802.11b, 802.11g, 802.11n, 802.11ac etc.
The term “Wi-Fi” is simply the marketing (trademark) name which encompasses all of the above technical standard terms from IEEE institute.
Let’s see a table with some important technical characteristics and features of each 802.11 standard before discussing the newest 802.11ax version.
|Standard Designation||Release Year||Frequency Band||Data Rate (Max)||Approx. Range (Indoor)||Comments|
|802.11a||1999||5 Ghz||54 Mbps||115 ft||Never used commercially|
|802.11b||1999||2.4 Ghz||11 Mbps||115 ft||Actual first useable standard|
|802.11g||2003||2.4 Ghz||54 Mbps||125 ft|
|802.11n||2009||2.4 Ghz and 5 Ghz||600 Mbps||230 ft||First dual band standard|
|802.11ac||2013||5 Ghz||3.47 Gbps||120-150 ft||All AC routers include also a 2.4Ghz radio (802.11n)|
|802.11ax||Est. 2019||2.4 Ghz and 5 Ghz concurrently||14 Gbps||Better than AC||Successor of AC (to be released in 2019)|
|802.11ad||2012||60 Ghz||6.7 Gbps||11 ft||Not widely used|
|802.11ay||Est.2020||60 Ghz||20 Gbps||33 ft||Successor of AD|
The most widely used wireless LAN standard at the time of this writing is 802.11ac which will be replaced by the new generation 802.11ax in the near future. This new generation of Wi-Fi is estimated to be officially finalized by the end of 2019.
As it is obvious from the table above, there are so many confusing acronyms and technical naming conventions so the Wi-Fi Alliance decided to simplify the IEEE standards above and give them more user-friendly names as shown below:
- WiFi 6 (802.11ax) – New Standard to be finalized in 2019
- WiFi 5 (802.11ac) – Currently the most popular standard
- WiFi 4 (802.11n)
- WiFi 3 (802.11g)
- WiFi 2 (802.11a)
- WiFi 1 (802.11b)
You must have in mind that the newest WiFi 6 will be backwards compatible with the older standards so even if you buy one of the new 802.11ax routers all of your home wireless clients will still work fine.
802.11ax (Wi-Fi 6) Unique Features
The new WiFi6 has the aspiration of becoming the new mainstream wireless LAN standard with wide commercial, user and vendor support.
To achieve the above goal, the new protocol will try to solve or minimize the following problems found in current WLAN networks:
- Airtime distribution among clients is not efficient.
- The wireless medium is shared among all clients.
- Networks with many clients (high density environments such as airports, public places etc) suffer from performance issues.
- High battery (power) consumption of mobile client devices when using WiFi.
The most important problem that the new AX standard will try to solve is better performance in high-density environments (congested areas) such as airports, home networks with many devices, Internet of Things (IoT) environments etc.
Especially the latter one (IoT) will be a rapidly evolved field thus WiFi 6 will prepare the networks for supporting so many wireless connected clients.
Here are some unique and new features that 802.11ax will provide (there are much more offered by the standard but I’m listing some important ones only):
- Introduction of OFDMA (Orthogonal frequency-division multiple access) which allows simultaneous transmissions from multiple users.
- MU-MIMO will be bi-directional (instead of downlink only).
- Usage of 160Mhz bandwidth channels for much faster wireless connections.
- Spacial Frequency Reuse.
- Target Wake Time (for better battery power utilization).
- Support for WPA3 security encryption standard which will offer enhanced security compared to the current WPA2.
Let’s discuss briefly each of the above unique features:
This technology is borrowed from the successful 4G LTE mobile communications technology. In a nutshell, each connected client to the wifi router will use sub-channels within the main overall Wi-Fi channel itself thus multiple client devices can transmit data to and from the router simultaneously.
This means that each client device will not have to wait for a clear channel before sending data, and will not have to worry about collisions in the wireless physical channel. Therefore, in dense environments OFDMA will allow multiple client devices to efficiently use the wireless channel resources.
In current 802.11ac standard, the technology of MU-MIMO (Multiple Users Multiple Input Multiple Output) is well supported especially in wave2 clients and routers.
However, current MU-MIMO is only uni-directional (downlink only).
Bi-directional MU-MIMO in 802.11ax will support up to 8 simultaneous users in downlink direction and up to 8 simultaneous users in uplink direction (client to router).
Modern home networks have a lot of uplink traffic. Sharing photos and videos on social media, uploading backup data to the cloud, video streaming from local cameras to the cloud etc. Therefore, this specific feature will enhance user experience and speed by many factors.
160Mhz bandwidth channels
What you should know in wireless communications, the higher the frequency the more data rate can flow through the channel.
Although 160Mhz channels are also available in AC standard, in AX standard with 1024 QAM modulation the 160Mhz channel feature is supposed to further enhance data throughput by around 25%.
Note however that you must have a suitable client wifi device that supports AX as well.
Spacial Frequency Reuse
This is another characteristic that will help a lot in RF-dense environments (and by “RF-dense” we don’t only mean having many client devices in the same WLAN but also having many different Access Points (wifi routers) in the same area although belonging in different networks – e.g in a dense neighborhood, multi-apartment buildings etc).
If let’s say your wireless router operates in the same frequency spectrum and channel as your neighbor (something very common), your smartphone or laptop will receive interference from the neighbor’s smartphones and laptops and this will affect the quality of communication.
With Spacial Frequency Reuse, simultaneous transmissions of both your own devices and your neighbor’s devices will be permitted by adjusting the power output of the device so that it won’t interfere with the other devices.
Target Wake Time
This one has to do with lower battery (power) consumption by using 802.11ax.
Basically the Access Point (router) and client devices will negotiate and define a specific time schedule to access the wireless medium. The rest of the time, the client device will be sleeping (in terms of radio wifi connectivity). This will reduce battery consumption significantly.
Wi-Fi Protected Access (WPA) has been the defacto standard offering security and encryption in wifi wireless networks. The original security mechanisms for wifi were WPA and WEP which suffer from serious security vulnerabilities and are not used any more.
The current protocol is WPA2 which is fairly secure (especially if you use a long and complex SSID security key) and is used extensively in current 802.11 networks.
Although WPA2 (released in 2004) is currently pretty good in terms of security, it started to become old since better and more efficient security protocols were introduced recently.
There are some notable improvements of WPA3 which will be the preferred security protocol of WiFi6. These features include individualized data encryption, brute-force attack protection, simplified connection of devices without display, 192-bit security suite etc.
802.11ac vs 802.11ax (WiFi5 vs WiFi6)
When the new standard will become mainstream and widely adopted, many people will be curious to know the similarities and differences between wifi5 and wifi6. Let’s discuss some of them below:
- WiFi5 (802.11ac) officially operates only on the 5Ghz frequency band although all commercial products (routers and client devices) are equipped also with a 2.4Ghz radio operating using the 802.11n standard.
- WiFi6 (802.11ax) on the other hand will natively support both 5Ghz and 2.4Ghz simultaneously with more supported channels (right now 12 total channels).
- MU-MIMO will be working bi-directional in wifi6 instead of uni-directional (downlink only) in wifi5
- OFDMA (which will greatly enhance performance) is available only on WiFi6
- WiFi6 will allow 8 simultaneous streams instead of 4 on WiFi5.
- Significant improvement in battery consumption in 802.11ax compared to ac standard.
802.11ax Speed (Data Rate)
In theory, the maximum throughput (wireless speed between your client devices and router) in 802.11ax will be around 14Gbps.
How this is derived? If we assume that 160Mhz channels are used with 4×4 MIMO streams, this equals to 4×3.5Gbps = 14Gbps. This is only in theory though and your client devices must be capable (hardware wise) of 4×4 MIMO in order to support the above.
The above max speed is around four times faster than current speeds of 802.11ac standard.
When we discuss coverage range of wireless technology, this is something you can’t assign a number to it.
Range in WLAN networks is a relative factor and depends on many things such as environmental conditions, structure of house, thickness and materials of walls etc.
The expectation of scientists developing this IEEE standard is that it will offer a small enhancement in range compared to existing standards not because there will be a specific boost in antennas or hardware but mainly because of the other technologies of Wi-Fi 6 that will reduce interference and increase performance in dense networks.
The above improvements will most likely result in a slight increase in wireless range.
Current 802.11ax Routers in the market
Many well-known manufacturers are early adopters of WiFi6 technology. New router models are being manufactured and launched as we speak. Here are all the available models in the market as of now:
- ASUS RT-AX88U (AX6000)
- ASUS ROG Rapture GT-AX11000
- NETGEAR Nighthawk AX8 (RAX80)
- NETGEAR Nighthawk AX12 (RAX120)
- NETGEAR Nighthawk TRI-BAND AX12 (RAX200)
- Netgear Orbi Wi-Fi 6 (coming soon)
- TP-LINK Archer AX11000
- TP-LINK Archer AX6000
Overall, like everything new in technology, the new Wi-Fi generation (WiFi6) will be an advancement in the right direction. However, it’s still in early stages and support from manufacturers will expand a lot in 2019 (both from chipset manufacturers like Intel, Broadcom, Qualcomm etc and also from WiFi manufacturers like Netgear, Asus, Linksys etc).