Discussion
Test Validation
Despite trying to minimize variable, any WiFi speed test can be highly variable due to many confounding factors. However, the test should demonstrate or confirm certain expected trends or relationship. If not, the test is grossly flawed. So let’s see if the data acquired have at least reasonable credibility.
Hypothesis: Speed should be faster when measured next to the access point when compared to 30 ft away.
Reason: The closer to the AP, the better signal strength and wireless physical link is.
Fact: Although all 3 clients for both access points indeed had faster speed when next to access points, iPad Pro had minimal drop in its speed even at 30ft distance. In fact, the difference here is likely statistically insignificant. Perhaps, iPad has better antenna?
Hypothesis: iPhone 11 Pro and iPad 11 Pro (2018) should have similar peak speed when connected to UniFi AP.
Reason: With UniFi AP, both device will have 2×2 MIMO WiFi 5 connection. So there should not be significant speed difference especially when next to the AP.
Fact: iPad Pro peak performance was 513 Mbps and iPhone 11 Pro was 528 Mbps so the difference is merely 15 Mbps, which is under 5%. So they are essentially the same.
At 28ft, iPad Pro retained most of its speed; however, iPhone Pro had significant speed reduction. So two became significantly different, but this may be due to the strength of client antenna for the range.
Hypothesis: iPhone 11 Pro should be faster than iPad 11 Pro (2018) when connected to Ax11000.
Reason: With Ax11000 node, iPhone 11 uses WiFi 6 technology; whereas, iPad remains at WiFi 5. Since both devices are 2×2 MIMO, there may be up to 40% speed advantage on iPhone 11 than iPad 11 according to Intel.
Fact: On this test, iPhone seemed to underperform on AiMesh system than what we expect. With AiMesh, iPhone had 474 Mbps average peak performance whereas iPad Pro had 401 Mbps. This calculated to be only 18% speed boost with WiFi 6. Based on my previous test, I saw Ax11000 in router mode showed 25% speed gain when compared to iPad Pro.
Hypothesis: Peak Performance Speed should be 50-70% of PHY.
Reason: 30-50% throughput loss with Wifi technology relates to the overhead and unavoidable. Since MBP is the only client I could easily look wireless physical link speed between each test, I only recorded that number. The reason we are limiting this to peak performance is because at range, the PHY was fluctuating.
Fact: AP-HD peformed 60% of PHY speed. Asus Ax11000 performed 50% of PHY speed. The latter is the number I got on the previous test using Ax11000 as router as well.
So absolute speed being aside, data trends and relationships appear what we expect. With these facts, we can confirm the test seemed credible. Now we can look at actual data and interpret what they mean.
Peak Performance Gain
For the peak performance, the result was a huge surprise to me with UniFi AP outperformed Ax11000 node in all 3 client devices. Even on WiFi 6 connected iPhone 11 Pro, there was 11% gain on UniFi over the AiMesh.
UniFi gave peak performance gain of over 11% even on WiFi 6 device.
Range Performance Gain
For the 30ft range performance, UniFi continued to outperform Ax11000 AiMesh but here difference are variable. On MBP, the difference being under 5%, which means they are essentially the same. For iPad and iPhone, relative performance lead of UniFi AP are not significantly changed from Ax11000.
UniFi continues to outperform AiMesh Ax11000 node even at 30ft distance.
WiFi 5 vs. WiFi 6
Now what about WiFi 5 vs. WiFi 6 comparison? iPhone 11 Pro table is a direct comparison of WiFi 5 against WiFi 6. With iPhone 11 Pro being 2×2 WiFi 6 capable, which is backward compatible so with Wifi 6 capable Ax11000 AiMesh node, the wireless physical link between two is WiFi 6. On the other hand, when Wifi 5 access point, UniFi HD is used, the link becomes WiFi 5.
This is the key part of test where I was hoping that with more efficient WiFi 5 system, single client range performance advantage of ~10% with WiFi 6 technology may be reduced.
The result was astonishing. Rather than closing the gap, UniFi actually outperformed flagship WiFi 6 device not only at the range performance, but even at peak performance by a substantial margin.
Overall performance In order
This is a table putting average speed in order. This is just another way to look how well UniFi did on both Peak and Range performance. What’s impressive here is iPad Pro with UniFi outperformed iPhone 11 with ASUS Ax11000. Generalizing this, under UniFi network WiFi 5 device can operate faster than WiFi 6 device in Asus AiMesh network.
under UniFi network WiFi 5 device can operate faster than WiFi 6 device in Asus AiMesh network.
Now this may be a bit too much generalization, but as of time of this writing (April 2020), I think it is safe to assume iPhone 11 Pro 2×2 MIMO operating 80 MHz is reasonable standard device.
Supportive Evidence
So my test basically says WiFi 6 really does not give throughput advantage. Could this be due to my setup/environment? Is it issue with Asus Ax11000?
SmallNetBuilder conducted WiFI 6 router performance test in more controlled environment with more expensive tools. They have compared 5 Wifi 6 routers: ASUS RT-Ax88U, Asus GT-AX11000, Netgear RAX40, RAX80 and RAX120. Their setup enabled 1024 QAM modulation and 80 MHz bandwidth. What’s missing for achieving marketing max throughput is 160 MHz bandwidth.
I did not run tests with 160 MHz bandwidth enabled on 5 GHz. Enabling 160 MHz requires using DFS channels, which aren’t available in all countries or reliably where public safety (including airport) radar is in use. I
Wi-Fi 6 Performance Roundup: Five Routers Tested
They had a test chamber with client mimicking device used 2×2 MIMO system capable of establishing 1201 Mbps WiFi 6 wireless physical link throughput at 80 MHz just like iPhone 11 Pro.
The result for 5GHz was…
There was no throughput gain observed from AX vs. AC when using 5 GHz. Even though our test STA got the expected 1201 Mbps link rate with all routers with the strongest signal, this did not translate to higher throughput. In fact, both AC and AX STAs were only able to get 700 Mbps at most and usually below that. 5 GHz uplink with the AC STA actually produced the highest throughput!
Wi-Fi 6 Performance Roundup: Five Routers Tested
So this truly confirms validity of my test and tells me it won’t matter if I try alternative WiFi 6 routers/access points from other manufactures.
One thing to note here is though, I did not test 2.4 GHz band and this is where WiFi 6 actually showed the gain.
In general, 2.4 GHz AX performance was better behaved than 5 GHz. Most products produced around 2X throughput when used with an AX STA vs. an AC STA. Right now, this is likely to be the thing that most buyers would notice from upgrading both router and device to Wi-Fi 6. Note that you’ll get this benefit even from using 20 MHz bandwidth and even with the lowest priced two-stream NETGEAR RAX40.
Wi-Fi 6 Performance Roundup: Five Routers Tested
Does this convince me about WiFi 6? No. absolutely not. The reason is 5 GHz band is by multiple factors faster than 2.4 GHz. So with a proper mesh or access points network, I should be able to get 5 GHz speed everywhere in my house. Those devices that use only 2.4 GHz or ones I want them to use 2.4 GHz e.g. Internet of Things (IOT) devices don’t need high speed anyways.
Conclusion
Although I always knew there were WiFi systems that have better stability than my current Wifi 6 Asus AiMesh setup, I believed that would come at the cost of speed and/or flexibility. From balancing of three core pillars of WiFi system (speed, stability and flexibility), I thought ASUS Wifi AiMesh system was the king at least on the paper.
However, I have (finally) started to realize stability/reliability are far more important factor than what I had been giving credit for. Especially, having high iPerf 3 or Internet speed test results did not impress any of my family member except 10 year old and nothing we do routinely ever uses the peak speed. So I was ready to give up some speed for stability even if I end up going back to WiFi 5 system as long as the loss is reasonable.
To my huge surprise, despite the lack of WiFi 6 support, UniFi access point (UAP-AC-HD) outperformed ASUS Wifi 6 router (Ax-11000) in AiMesh mode for the speed by a substantial margin even for WiFi 6 client. Based on the reputation, I expect UniFi would have better stability. So once I got this test result, the same night, I have ended up ordering UniFi Dream Machine Pro and UAP nano HD. I am ready to give full chance to UniFi network.