Apr 22, 2019 - 802.11ac offers backward compatibility to 802.11b/g/n and bandwidth rated up to 1300 Mbps on the 5 GHz band plus up to 450 Mbps on 2.4 GHz. Most home wireless routers are compliant with this standard. Jump to Top FlashRouters By Maximum Speeds - Wireless-AC 3200 Mbps Linksys WRT3200ACM DD-WRT – Best Recommended Wireless-AC Router.
Dazzling users with specification sheets is nothing new: screen sizes, resolutions, megapixels, memory sizes and processor speeds are just a few, but one of the most neglected and important is WiFi and its latest and greatest standard ‘802.11ac’.802.11ac was finalised in 2013 and you will find it in every major smartphone, laptop and desktop computer and smart television. It succeeds the equally-badly named ‘802.11n’ which has been around since 2007 and brings some major benefits.
The good news is by the end of this post you will not only understand 802.11ac, but also how to get the best from your existing wireless signal.
Compatibility - Everything Works Together
I’ll start with the good news: chipsets featuring 802.11ac are fully backwards compatible with previous WiFi standards.
WiFi official logo and accepted standards
This means it works perfectly with 802.11a (introduced in 1999), 802.11b (2000), 802.11g (2003) and 802.11n (2007). The bad news is you will be limited to the performance of the older standard and will only get the full benefits of ‘Wireless AC’ or ‘AC WiFi’, as it is also known, if you are connecting from 802.11ac to 802.11ac. That means an 802.11ac router and an 802.11ac device.
So that out the way, what are the benefits?
802.aac theoretical speeds versus 802.11n and 802.11g - image credit Asus
802.11ac vs 802.11n Speed
You may have noticed there has been a six year gap between 802.11n and 802.11ac. This is an eternity in technology terms and the big benefit 802.11ac brings from its time in development is speed.
WiFi is always promoted using ‘theoretical’ speeds and by this standard 802.11ac is capable of 1300 megabits per second (Mbps) which is the equivalent of 162.5 megabytes per second (MBps). This is 3x faster than the typical 450Mbps speed attributed to 802.11n.
The problem is these speeds are garbage. In the real world no-one ever gets close to theoretical speeds and the fastest 802.11ac real world speeds recorded in testing are around 720Mbps (90MBps). By contrast 802.11n tops out at about 240Mbps (30MBps) so the 3x estimate is still true, just much lower.
But there is one more crucial part to understand for your real world experience: antennas.
Long term 802.11ac has the headroom to support up to eight antennas each running at over 400Mbps each, but the fastest router to date only has four antennas. The reason is because antennas add cost and take up space and the smaller the device the less antennas they can fit so it becomes pointless adding more to a router. Typically:
- Smartphones: 1 antenna
- USB Adaptors: 1 or 2 antennas
- Tablets: 2 antennas
- Laptops: 2 antennas (occasionally 3 on desktop replacements)
- Desktops: 3 or 4 antennas (PCI
Express cards)
This is another bottleneck. If your glorious four antenna 802.11ac router is connecting to your single antenna 802.11ac smartphone then 400Mbps (50Mbps) is your theoretical maximum and 200Mbps (25MBps) is the more realistic one.
This is something of a downer, but these speeds are still faster than nearly all home broadband connections and only become a limitation for transferring files wirelessly between devices on your local network (say laptop to laptop or desktop to NAS).
Furthermore 802.11n only supports up to four antennas at roughly 100Mbps (12.5MBps) each so when you do the maths for devices using 802.11n antennas the gap begins to widen. Especially when it comes to the next big benefit of 802.11ac…
Beamforming 'Smart WiFi' - image credit Netgear
802.11ac vs 802.11n Range
So AC WiFi is much faster, but its peak speeds are not really the selling point. It’s speeds at long range are.
First the bad news: 802.11ac WiFi doesn’t really reach any further than 802.11n WiFi. In fact 802.11ac uses the 5GHz band while 802.11n uses 5GHz and 2.4GHz. Higher bands are faster but lower bands travel further.
That said my experience testing both standards finds very little difference in signal strength between 802.11ac over 5GHz and 802.11n over 5GHz and 2.4GHz.
Why? Firstly because 2.4GHz is used for everything from cordless home phones to microwaves and 5GHz remains relatively interference free for a cleaner signal.
The second key factor is ‘Beamforming’. Typically wireless signal is simply thrown out from your router equally in all directions, like ripples when throwing a stone into a pond. This is why you should place your router as close to the centre of your home or office and as high up as possible.
Beamforming is different. It is built into the 802.11ac specification and is ‘smart signal’ which detects where connected devices are and increases signal strength specifically in their direction. Yes it is still a good idea to position your router centrally, but it helps make it less vital.
All this means the performance of 802.11ac is maintained far better at long range than 802.11n. Peak performance may be tripled, but at range 5-10x the speed benefits are not unusual and this is where 802.11ac comes into its own. Some numbers for example:
- 802.11ac at one metre: 90MBps, 10 metres: 70MBps and at 20 metres behind two solid walls: 50MBps
- 802.11n at one metre: 30MBps, 10 metres: 20MBps and at 20 metres behind two solid walls: 5-10MBps
Of course these figures are a general guide and I’ll get into examples of more specific top 802.11ac devices to buy next.
802.11ac ns 802.11n Availability and Price
Technology is a wonderful thing. 12 months ago 802.11ac equipment was hard to find and extremely expensive. Now it is built into every premium smartphone, tablet, laptop and smart TV and is increasingly found in midrange devices as well.
The reason for this is threefold. Firstly there are obvious performance benefits, particularly for single antenna devices like smartphones. Secondly it is more battery efficient because WiFi needs to be active for less time when data transfers can complete more quickly. Thirdly with proliferation comes scales of economy which bring down the price.
One caveat: make sure you find officially certified devices (using the official WiFi logo). Some devices are still use ‘Draft’ 802.11ac and while they tend to work fine and should eventually update, it isn’t guaranteed.
When it comes to pricing most devices you buy have already integrated 802.11ac so you won’t be consciously paying more for it.
Where there is still a jump in price, however, is routers. Wireless AC routers still tend to have a 20-50% premium (depending on model), but as ageing routers risk becoming the speed and range bottleneck for every Internet connected item in your home these much neglected devices are worth a little more investment.
D-Link DIR-880L - image credit D-Link
Recommended 802.11ac Kit
Like any area of technology the market is always changing, but at the time of writing these are my top 802.11ac kit recommendations.
Best Value Router
D-Link DIR-880L - $180 - The current price/performance champ. It lacks an integrated modem, but has the potential to supercharge your WiFi network for a fraction of the cost of rivals
Best Performing Router
Netgear R7500 Nighthawk X4 - $280 - The first of the next wave of so-called ‘AC2350’ routers (1300Mbps AC WiFi combined boosted 600Mbps N WiFi and rounded up!). You’ll need a fat wallet and proprietary desktop PCI adaptor (more below) to get the best from it.
Best Peripheral
Asus PCE-AC68 PCI Adaptor - $99 - If you want your desktop PC to have the fastest possible wireless experience this is the beast to get. Watch out for the PCE-AC87 which Asus will launch soon for the ‘AC2350’ routers, but this should be more than enough for most.
Best USB Adaptor
D-Link DWA-171 - $24 - there are faster dual antenna AC1200 USB dongles, but they are huge whereas the slower DWA-171 is so small you can leave it in a laptop at all times and it still delivers strong performance.
___
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Express cards)This is another bottleneck. If your glorious four antenna 802.11ac router is connecting to your single antenna 802.11ac smartphone then 400Mbps (50Mbps) is your theoretical maximum and 200Mbps (25MBps) is the more realistic one.
This is something of a downer, but these speeds are still faster than nearly all home broadband connections and only become a limitation for transferring files wirelessly between devices on your local network (say laptop to laptop or desktop to NAS).
Furthermore 802.11n only supports up to four antennas at roughly 100Mbps (12.5MBps) each so when you do the maths for devices using 802.11n antennas the gap begins to widen. Especially when it comes to the next big benefit of 802.11ac…
802.11ac vs 802.11n Range
So AC WiFi is much faster, but its peak speeds are not really the selling point. It’s speeds at long range are.
First the bad news: 802.11ac WiFi doesn’t really reach any further than 802.11n WiFi. In fact 802.11ac uses the 5GHz band while 802.11n uses 5GHz and 2.4GHz. Higher bands are faster but lower bands travel further.
That said my experience testing both standards finds very little difference in signal strength between 802.11ac over 5GHz and 802.11n over 5GHz and 2.4GHz.
Why? Firstly because 2.4GHz is used for everything from cordless home phones to microwaves and 5GHz remains relatively interference free for a cleaner signal.
The second key factor is ‘Beamforming’. Typically wireless signal is simply thrown out from your router equally in all directions, like ripples when throwing a stone into a pond. This is why you should place your router as close to the centre of your home or office and as high up as possible.
Beamforming is different. It is built into the 802.11ac specification and is ‘smart signal’ which detects where connected devices are and increases signal strength specifically in their direction. Yes it is still a good idea to position your router centrally, but it helps make it less vital.
All this means the performance of 802.11ac is maintained far better at long range than 802.11n. Peak performance may be tripled, but at range 5-10x the speed benefits are not unusual and this is where 802.11ac comes into its own. Some numbers for example:
- 802.11ac at one metre: 90MBps, 10 metres: 70MBps and at 20 metres behind two solid walls: 50MBps
- 802.11n at one metre: 30MBps, 10 metres: 20MBps and at 20 metres behind two solid walls: 5-10MBps
Of course these figures are a general guide and I’ll get into examples of more specific top 802.11ac devices to buy next.
802.11ac ns 802.11n Availability and Price
Technology is a wonderful thing. 12 months ago 802.11ac equipment was hard to find and extremely expensive. Now it is built into every premium smartphone, tablet, laptop and smart TV and is increasingly found in midrange devices as well.
The reason for this is threefold. Firstly there are obvious performance benefits, particularly for single antenna devices like smartphones. Secondly it is more battery efficient because WiFi needs to be active for less time when data transfers can complete more quickly. Thirdly with proliferation comes scales of economy which bring down the price.
One caveat: make sure you find officially certified devices (using the official WiFi logo). Some devices are still use ‘Draft’ 802.11ac and while they tend to work fine and should eventually update, it isn’t guaranteed.
When it comes to pricing most devices you buy have already integrated 802.11ac so you won’t be consciously paying more for it.
Where there is still a jump in price, however, is routers. Wireless AC routers still tend to have a 20-50% premium (depending on model), but as ageing routers risk becoming the speed and range bottleneck for every Internet connected item in your home these much neglected devices are worth a little more investment.
![Wireless A B G N Ac Speeds Wireless A B G N Ac Speeds](/uploads/1/2/3/7/123748565/489679670.png)
Recommended 802.11ac Kit
Like any area of technology the market is always changing, but at the time of writing these are my top 802.11ac kit recommendations.
Best Value Router
D-Link DIR-880L - $180 - The current price/performance champ. It lacks an integrated modem, but has the potential to supercharge your WiFi network for a fraction of the cost of rivals
Best Performing Router
Netgear R7500 Nighthawk X4 - $280 - The first of the next wave of so-called ‘AC2350’ routers (1300Mbps AC WiFi combined boosted 600Mbps N WiFi and rounded up!). You’ll need a fat wallet and proprietary desktop PCI adaptor (more below) to get the best from it.
Best Peripheral
Asus PCE-AC68 PCI Adaptor - $99 - If you want your desktop PC to have the fastest possible wireless experience this is the beast to get. Watch out for the PCE-AC87 which Asus will launch soon for the ‘AC2350’ routers, but this should be more than enough for most.
Best USB Adaptor
D-Link DWA-171 - $24 - there are faster dual antenna AC1200 USB dongles, but they are huge whereas the slower DWA-171 is so small you can leave it in a laptop at all times and it still delivers strong performance.
___
More on Forbes
In the world of wireless, the term Wi-Fi is synonymous with wireless access in general, despite the fact that it is a specific trademark owned by the Wi-Fi Alliance, a group dedicated to certifying that Wi-Fi products meet the IEEE’s set of 802.11 wireless standards.
These standards, with names such as 802.11b (pronounced “Eight-O-Two-Eleven-Bee”, ignore the “dot”) and 802.11ac, comprise a family of specifications that started in the 1990s and continues to grow today. The 802.11 standards codify improvements that boost wireless throughput and range as well as the use of new frequencies as they become available. They also address new technologies that reduce power consumption.
What is Wi-Fi 6? Wi-Fi 5? Wi-Fi 4?
The IEEE naming scheme for the standard is a little tough to get used to, and in an effort to make it easier to understand, the Wi-Fi Alliance has come up with some simpler names.
Under its naming convention, the alliance calls 802.11ax Wi-Fi 6. 802.11ac is now Wi-Fi 5, and 802.11n is Wi-Fi 4. The idea, according to the Wi-Fi Alliance, is to make matching endpoint and router capabilities a simpler matter for the rank-and-file user of Wi-Fi technology.
Meanwhile it's important to know that the Wi-Fi Alliance has not made up simpler names for all the 802.11 standars, so it's important to be familiar with the traditional designations. Also, the IEEE, which continues to work on newer versions of 802.11, has not adopted these new names, so trying to track down details about them using the new names will make the task more complicated.
The traditional names of these standards create quite an alphabet soup, made all-the-more confusing because they are not arranged alphabetically. To help clarify the situation, here’s an update on these physical-layer standards within 802.11, listed in reverse chronological order, with the newest standards at the top, and the oldest toward the bottom. After that is a description of standards that are still in the works.
802.11ah
Also known as Wi-Fi HaLow, 802.11ah defines operation of license-exempt networks in frequency bands below 1GHz (typically the 900 MHz band), excluding the TV White Space bands. In the U.S., this includes 908-928MHz, with varying frequencies in other countries. The purpose of 802.11ah is to create extended-range Wi-Fi networks that go beyond typical networks in the 2.4GHz and 5GHz space (remember, lower frequency means longer range), with data speeds up to 347Mbps. In addition, the standard aims to have lower energy consumption, useful for Internet of Things devices to communicate across long ranges without using a lot of energy. But it also could compete with Bluetooth technologies in the home due to its lower energy needs. The protocol was approved in September 2016 and published in May 2017.
802.11ad
Approved in December 2012, 802.11ad is very fast - it can provide up to 6.7Gbps of data rate across the 60 GHz frequency, but that comes at a cost of distance – you achieve this only if your client device is situated within 3.3 meters (only 11 feet) of the access point.
802.11ac (Wi-Fi 5)
Current home wireless routers are likely 802.1ac-compliant, and operate in the 5 GHz frequency space. With Multiple Input, Multiple Output (MIMO) – multiple antennas on sending and receiving devices to reduce error and boost speed – this standard supports data rates up to 3.46Gbps. Some router vendors include technologies that support the 2.4GHz frequency via 802.11n, providing support for older client devices that may have 802.11b/g/n radios, but also providing additional bandwidth for improved data rates.
802.11n (Wi-Fi 4)
The first standard to specify MIMO, 802.11n was approved in October 2009 and allows for usage in two frequencies - 2.4GHz and 5GHz, with speeds up to 600Mbps. When you hear wireless LAN vendors use the term “dual-band”, it refers to being able to deliver data across these two frequencies.
802.11g
Approved in June 2003, 802.11g was the successor to 802.11b, able to achieve up to 54Mbps rates in the 2.4GHz band, matching 802.11a speed but within the lower frequency range.
802.11a
The first “letter” following the June 1997 approval of the 802.11 standard, this one provided for operation in the 5GHz frequency, with data rates up to 54Mbps. Counterintuitively, 802.11a came out later than 802.11b, causing some confusion in the marketplace because eople expected that the standard with the 'b' at the end would be backward compatible with the one with the 'a' at the end.
802.11b
Released in September 1999, it’s most likely that your first home router was 802.11b, which operates in the 2.4GHz frequency and provides a data rate up to 11 Mbps. Interestingly, 802.11a products hit the market before 802.11a, which was approved at the same time but didn’t hit the market until later.
802.11-1997
The first standard, providing a data rate up to 2 Mbps in the 2.4GHz frequency. It provided a range of a whopping 66 feet of indoors (330 feet outdoors), so if you owned one of these routers, you probably only used it in a single room.
Pending Wi-Fi standards
802.11aj
Also known as China Millimeter Wave, this defines modifications to the 802.11ad physical layer and MAC layer to enable operation in the China 59-64GHz frequency band. The goal is to maintain backward compatibility with 802.11ad (60GHz) when it operates in that 59-64GHz range and to operate in the China 45GHz band, while maintaining the 802.11 user experience. Final approval was expected in November 2017.
802.11ak
There are some products in the home-entertainment and industrial-control spaces that have 802.11 wireless capability and 802.3 Ethernet function. The goal of this standard is to help 802.11 media provide internal connections as transit links within 802.1q bridged networks, especially in the areas of data rates, standardized security and quality-of-service improvements. It reached draft status in November 2017.
802.11ax (Wi-Fi 6)
Known as High Efficiency WLAN, 802.11ax aims to improve the performance in WLAN deployments in dense scenarios, such as sports stadiums and airports, while still operating in the 2.4GHz and 5GHz spectrum. The group is targeting at least a 4X improvement in throughput compared to 802.11n and 802.11ac., through moreefficient spectrum utilization. Approval is estimated to be in July 2019.
802.11ay
Also known as Next Generation 60GHz, the goal of this standard is to support a maximum throughput of at least 20Gbps within the 60GHz frequency (802.11ad currently achieves up to 7Gbps), as well as increase the range and reliability. The standard is expected to be approved between September and November 2019.
802.11az
Called Next Generation Positioning (NGP), a study group was formed in January 2015 to address the needs of a “Station to identify its absolute and relative position to another station or stations it’s either associated or unassociated with.” The goals of the group would be to define modifications to the MAC and PHY layers that enable “determination of absolute and relative position with better accuracy with respect to the Fine Timing Measurement (MTM) protocol executing on the same PHY-type, while reducing existing wireless medium use and power consumption, and is scalable to dense deployments.” The current estimate on approval of this standard is March 2021.
802.11ba
Otherwise known as “Wake-Up Radio” (WUR), this isn’t a crazy morning zoo-crew thing, but rather a new technology aimed at extending the battery life of devices and sensors within an Internet of Things network. The goal of the WUR is to “greatly reduce the need for frequent recharging and replacement of batteries while still maintaining optimum device performance.” This is currently expected to be approved in July 2020.
Keith Shaw was a former Network World senior editor and writer of the Cool Tools column. He is now a freelance writer and editor from Worcester, Mass.
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