U6-Enterprise Preview: UniFi's First Wi-Fi 6E AP
Originally Posted: February 13th, 2022
Last Edited: October 13th, 2022
UniFi U6-Enterprise Preview and Wi-Fi 6E Deep Dive
Wi-Fi 7 (802.11be) is under development, but Wi-Fi 6E is here. Adoption and supply chain issues have limited it’s impact, but the Wi-Fi Alliance estimates that 350 million Wi-Fi 6E devices will enter the market in 2022. On February 11th, 2022, Ubiquiti added their first Wi-Fi 6E access point to their early access store, the U6-Enterprise.
The Access Point WiFi 6 Enterprise (U6 Enterprise) is a next-generation, enterprise-grade access point designed to take advantage of WiFi 6E speeds. Ideal for demanding, high-density networks, the U6 Enterprise can support up to 600+ clients over its 2.4, 5, and 6 GHz channels. Each of the U6 Enterprise's three bands also utilizes OFDMA technology, which tactically distributes high volumes of data to ensure that your clients maintain a reliably fast, quality connection.
On June 17th, 2022, Ubiquiti added the U6-Enterprise-In-Wall, which is another tri-band Wi-Fi 6E model. The Enterprise In-Wall is much larger than the older AC-In-Wall and AC-In-Wall-HD, covering a full 2-gang (double) outlet rather than a 1-gang (single) outlet that the past models covered. The Enterprise In-Wall can still be mounted to a 1-gang outlet, with the included wall plate adapter. It just needs more space for it's hotter components, 2.5 Gbps uplink, and tri-band antenna and radio array.
Since Ubiquiti prohibits product reviews of Early Access equipment, we can’t cover the details of how the U6-Enterprise performs. If you're interested in a comparison of all other UniFi APs, see my UniFi Wi-Fi Access Point Buyers Guide and my U6-Pro and U6-Mesh Review and Speed Comparisons. In the mean time, it is also helpful to understand what Wi-Fi 6E is, and how 6 GHz differs from 2.4 GHz and 5 GHz. Strap in, relax your shoulders, and grab a beverage. This dive is going deep.
Table of Contents
Specifications
U6-Enterprise Specs
Powerful, ceiling-mounted WiFi 6E access point designed to provide seamless, multi-band coverage within high-density client environments.
- Radios
- Tri-band, 10.2 Gbps aggregate throughput rate
- 6 GHz
- 4x4 DL/UL MU-MIMO and OFDMA
- Max Radio Rate: 4.8 Gbps
- Max TX Power: 26 dBm (6 GHz limited by PSD, not EIRP)
- Antenna Gain: 6 dBi
- 5 GHz
- 4x4 DL/UL MU-MIMO and OFDMA
- Max Radio Rate: 4.8 Gbps
- Max TX Power: 26 dBm
- Antenna Gain: 5.3 dBi
- 2.4 GHz
- 2x2 UL MU-MIMO
- Max Radio Rate: 570 Mbps
- Max TX Power: 22 dBm
- Antenna Gain: 3.2 dBi
- Ports and Power
- (1) 2.5GbE RJ45 Ethernet Input
- Powered with 802.3at PoE+
- PoE injector not included
- Optimized for use with USW Enterprise switches, supporting 2.5GbE PoE switching
- Supports up to 600+ clients
- Included mounting plate, backing plate, and screw kit for quick and easy installation
- $299 US MSRP
U6-Enterprise-In-Wall Specs
Sleek, wall-mounted WiFi 6E access point with an integrated four-port switch designed for high-density office networks.
- Radios
- Tri-band, 10.2 Gbps aggregate throughput rate
- 6 GHz
- 4x4 DL/UL MU-MIMO and OFDMA
- Max Radio Rate: 4.8 Gbps
- Max TX Power: 26 dBm (6 GHz limited by PSD, not EIRP)
- Antenna Gain: 5.8 dBi
- 5 GHz
- 4x4 DL/UL MU-MIMO and OFDMA
- Max Radio Rate: 4.8 Gbps
- Max TX Power: 26 dBm
- Antenna Gain: 5.8 dBi
- 2.4 GHz
- 2x2 UL MU-MIMO
- Max Radio Rate: 570 Mbps
- Max TX Power: 22 dBm
- Antenna Gain: 4 dBi
- Ports and Power
- (1) 2.5GbE RJ45 Ethernet Input
- 4-port Gigabit switch with (1) PoE passthrough output
- Powered with 802.3at 30W PoE+, 802.3bt 60W PoE++, or 48V PoE injector input
- PoE passthrough requires PoE++ in
- PoE injector not included
- Supports up to 600+ clients
- Included aluminum mounting plate and screw kit for quick and easy installation over top of single or double duplex wall outlet.
- $299 US MSRP
Nerdy Details of the U6-Enterprise
The specs of the U6-Enterprise and U6-Enterprise-In-Wall are straightforward, but 6 GHz Wi-Fi isn’t. Wi-Fi is a complicated technology that is often misunderstood. That’s especially true with newer standards and revisions such as Wi-Fi 6E and Wi-Fi 6 Release 2.
Thankfully, there are a lot of good white papers on Wi-Fi 6E, and the U6-Enterprise has been in the FCC database since July 2021. The public listing of the regulatory paperwork reveals a few other details.
- The FCC model ID is SWX-U6EP
- Ubiquiti’s original application was rejected, and this rejection letter from August 2021 is a fun read.
- The rules governing 6 GHz certification for the FCC are described here.
- The U6-Enterprise is a 61D class Low Power Indoor (LPI) Access Point.
- The U6-Enterprise will support DFS operation in 5 GHz, and 4x4 MIMO with 160 MHz channels in 5 GHz and 6 GHz.
- It’s the same size and shape as the U6-LR and AC-HD.
- The U6-Enterprise doesn’t come with a power injector, and all the injectors Ubiquiti sells only support 100 Mbps or 1 Gbps connections. To power the U6-Enterprise and get a 2.5 Gbps Ethernet connection, you’ll need:
- Switch Enterprise 8 PoE - $479
- Switch Enterprise 24 PoE - $799
- Switch Enterprise 48 PoE - $1,599
- 3rd Party switch capable of 2.5 Gbps and 802.3at PoE+
- 3rd party PoE injector such as TRENDnet’s TPE-215GI with a 2.5 Gbps switch.
- Of course, you can plug it into a Gigabit PoE+ injector or Gigabit Ethernet PoE+ switch. But is that really living?
What is Wi-Fi 6E?
In April 2020 the United States FCC voted to allow the unlicensed use of the 6 GHz band. This added 1200 MHz of spectrum (5.925 to 7.125 GHz) for devices like Wi-Fi access points. Previously, devices operating in this band had to be licensed, which prevented use by the general public. Since then more than 70 countries have followed, with some opting for different rules. Some areas such as the European Union chose to only allow unlicensed operation in the U-NII-5 band, adding 500 MHz rather than the full 1200 MHz. Chuck Lukaszewski has a great overview of the current status of Wi-Fi 6E on the Wi-Fi Alliance Beacon blog.
For perspective, there is around 260 MHz of unrestricted spectrum available in the 2.4 GHz and 5 GHz bands. The exact channels available vary by region, and it’s easy to get bogged down in specifics. What matters is that this limited amount of contiguous spectrum makes it difficult to enable wider 80 MHz or 160 MHz channels. Wider channels offer higher throughput, but also present a lot of issues and design challenges such as channel re-use and interference when used in the crowded 2.4 GHz and 5 GHz bands.
The desire for wider channels and more continuous spectrum is why the addition of the 6 GHz spectrum is such an important change. The additional 1200 MHz of spectrum comes with more asterisks and details than I cover below. If you’re interested in more depth, search for Wi-Fi 6E white papers such as A Guide to Wi-Fi 6E from Litepoint (direct PDF link).
5 GHz vs. 6 GHz Wi-Fi Speed and Coverage
There’s nothing special about 6 GHz to reduce latency, or increase speeds. Wi-Fi 6E uses the same PHY standard, MIMO, and modulation rates from Wi-Fi 6. The only new thing is the 6 GHz spectrum, and the rules surrounding its use. An 80 MHz channel in 5 GHz is going to perform similar to an 80 MHz channel in 6 GHz, with a few caveats:
- Higher frequencies attenuate faster, so 6 GHz signals by their nature offer slightly less range than 5 GHz. This varies by channel, but can be roughly estimated as a 10% reduction in range at a given power level. AP placement for good 5 GHz and 6 GHz coverage is nearly identical.
- 6 GHz offers more channels and should have less issues with interference. 6 GHz allows for up to seven 160 MHz channels or fourteen 80 MHz channels, depending on the rules in your area. This additional spectrum makes wide channels more usable in the real world, especially in networks with multiple APs.
- Wi-Fi 6E APs are typically tri-band to maintain backwards compatibility. Only Wi-Fi 6E clients can use the 6 GHz radio, all other clients have to use 2.4 or 5 GHz.
- In general, 6 GHz might be faster, if you’re near an AP using wide channels. 2.4 GHz and 5 GHz still have advantages, such as longer range, better wall penetration, and legacy compatibility.
Nerdy Details of 6 GHz and Wi-Fi 6E
EIRP vs. PSD
Traditionally, an APs power is measured with EIRP. Effective Isotropic Radiated Power (EIRP) is a measurement of radiated output power from an ideal isotropic antenna in a single direction. At the most basic level, transmit power and antenna gain are added together to get an AP’s EIRP.
- Transmit power = How loud it yells
- Antenna gain = How powerful its megaphone is
- EIRP = How loud it is, when it yells into its megaphone
Decibels (dB) are a logarithmic measure of power. Antenna gain is usually shown in dBi, and EIRP is measured in dBm, or decibels per milliwatt. Generally speaking, higher transmit power, higher antenna gain, higher EIRP = more range. The true range of any AP depends on where you put it, what’s around it, what device you’re using, and a bunch of other factors.
Another way to measure an APs power is spectral power density (PSD). Wi-Fi PSD is usually shown as dBm/MHz, meaning it takes into account both power and channel width.
Wi-Fi devices in the 2.4 GHz and 5 GHz bands are restricted by maximum EIRP, which is constant across channel sizes. This has the side effect of imposing a noise penalty on wider channels. With every doubling of channel width, the noise on the channel doubles as well. With a constant EIRP, that means that wider channels have a lower signal-to-noise (SNR) ratio, and lower spectral density. This reduces the effective range of wide channels in relation to narrow channels. Wide channels behave well with a strong signal, but narrow channels work better at range, and in noisy environments.
6 GHz Wi-Fi devices are restricted to a constant maximum power spectral density. When you double your channel bandwidth, you also can double (+3 dB) your EIRP, allowing for a consistent SNR with wider channels. This is easier to understand when you see it in a chart.
PSD and EIRP values for 6 GHz Wi-Fi devices. Image credit: mist.com
For more on power spectral density, Mist has a great explainer on EIRP, PSD, and how they relate. Oh, and don’t forget about MIMO gain, which is 3 dB for 2x2 APs, or 6 dB for 4x4 APs.
US FCC 6 GHz Power Limit Implications
- Max EIRP in 6 GHz varies by channel width
- Standard power APs:
- Indoor or outdoor
- Max EIRP = 36 dBm
- Max PSD = 23 dBm/MHz
- Operate in the U-NII-5 and U-NII-7 bands (5925 - 6425 MHz, or 6525 - 6875 MHz)
- Require the use of the new AFC system, which is similar to DFS in 5 GHz. They need to report their location to check for nearby incumbent users before being able to operate at their full power.
- Low-power indoor APs like the U6-Enterprise:
- Indoor only
- Max EIRP = 30 dBm
- Max PSD = 5 dBm/MHz
- Operate over the full 1200 MHz
- Do not require AFC
- Wi-Fi 6E client devices are always restricted to 6 dB lower than their access point.
Understanding Wi-Fi Speed
The U6-Enterprise is the first UniFi AP with a 2.5 Gbps Ethernet port, but it's not the first to offer multi-gig uplink speeds. The $799 UAP-XG and $1,499 UWB-XG both offer 10 Gbps Ethernet ports. APs that have dual Gigabit Ethernet ports like the AC-HD can use aggregation to get to 2 Gbps. The U6-Enterprise offers a single 2.5 Gbps port, but when will 1 Gbps become a bottleneck?
The U6-Enterprise claims “10.2 Gbps aggregate, over-the-air radio rate”, but where does that number come from? Why are the numbers what they are, and why don’t I get 10,200 Mbps on my speed tests, dang it!?
The short answer is: Wi-Fi transmissions have a lot of overhead. I covered this in more detail in Understanding Wi-Fi Speed, but these are some of the main contributors to overhead in Wi-Fi, and why you’ll never see 10.2 Gbps of throughput. To keep things simple, let’s start with a single client.
- Start With 10,200 Mbps
- Go down to one band = 4800 Mbps for 5 or 6 GHz
- Limit MIMO to 2x2 = 2400 Mbps
- If using 5 GHz, set channel width to 80 MHz or lower = 1200 Mbps
Already, from a best-case scenario wireless connection, a typical single client device will top out at a 1200 Mbps data rate. You'll never acheive 1200 Mbps of throughput with that data rate, due to the imperfect nature of wireless connections, and all the overhead that comes with them. Realistically, most Wi-Fi connections have these limits and sources or overhead:
- Reduce modulation/coding from 1024-QAM to 256-QAM or lower
- Account for TCP/IP overhead, normally a few percent
- Beacons and management traffic consume small amounts of airtime
- Wi-Fi is (mostly) half-duplex: only one device can transmit on the channel at a time
- Wi-Fi is a shared medium: collisions and re-transmissions consume airtime and reduce throughput
- The displayed PHY link rate is an estimate, and an average
After accounting for all the sources of overhead and gaps between frames, getting 50 to 70% of your advertised link rate in TCP throughput is usually the best you can hope for.
- A 2x2 device on an 80 MHz channel can achieve a maximum link rate of 1200 Mbps, resulting in throughput around 600-900 Mbps in ideal conditions.
- A 2x2 device on a 160 MHz channel can achieve a maximum link rate of 2400 Mbps, resulting in throughput around 1200-1600 Mbps in ideal conditions.
The Case For 2.5 Gbps Uplinks
Can you break the 1 Gbps barrier with a single client using 80 or 160 MHz channels? Yes, and that’s true with 5 GHz or 6 GHz. Wider channels are more realistic to use in 6 GHz, so these kind of extreme link rates and throughput values are more easily achieved with Wi-Fi 6E networks. Even then, you’ll need the right conditions, devices that are capable of sending and receiving at that speed, and an application or use case that can leverage it.
What I didn’t consider above is multi-user situations. For that, Small Net Builder has a great look at aggregate throughput and the impact of 2.5 Gbps Ethernet. I’d agree with his bottom line recommendation that all Wi-Fi 6 equipment should have a 2.5 Gbps Ethernet port. Can a single 1 Gbps uplink be a bottleneck on the U6-Enterprise, or any Wi-Fi 6 AP? In the right conditions, yes.
It’s easy to see numbers like 10.2 Gbps or 4,800 Mbps and think you’re getting screwed, but how often will you see more than 1 Gbps of throughput, in a single direction, on a single AP? I’ve personally never run into that limitation on any multi-AP network I’ve administered, including networks with 1000s of users spread over 100+ APs. Times are changing though, and devices are getting more data hungry all the time.
For better or worse, Ubiquiti is reserving multi-gig Ethernet for only their most expensive APs and switches. Some other manufacturers offer cheaper 2.5 Gbps and 5 Gbps options, but Gigabit Ethernet is going to be with us for a long time. As time goes on the cost of a multi-gig network will go down, and the ability to leverage it will go up.
Wi-Fi 6E and 6 GHz offers no shortage of asterisks, complications, and quirks. It also offers a lot to look forward to. We’re in the early adopter phase, where prices are high and benefits aren’t always obvious. Those that are willing to make the jump right now will have to deal with higher costs, limited availability, and early bugs.
The good news is that if the extra cost is worth it to you, Ubiquiti finally offers Wi-Fi 6E. Now we can all start telling people to wait for Wi-Fi 7.
