Test 4: 80 & 160 MHz Networks - Both Ch 36
With the 80 MHz channel width tests out of the way, I next enabled the NETGEAR's HT160 mode and set the ASUS channel back to 36. The Pal connected to the NETGEAR was also set to use 160 MHz wide channels.
80 MHz & 160 MHz networks - Both Ch 36 - Downlink
AP1 AVG= 195 Mbps AP2 AVG = 344 Mbps
Well, this is encouraging. The two networks behave similarly to when both were using 80 MHz wide channels. The 80 MHz channel network running on the ASUS still had lower throughput than the 160 MHz channel network running on the NETGEAR. But the difference is again around 20% for downlink and 40% for uplink.
Conclusion: 160 MHz wide channels appear to have the same effect on a neighboring network using 80 MHz channels as a neighboring network using 80 MHz wide channels.
80 MHz & 160 MHz networks - Both Ch 36 - Uplink
AP1 AVG= 252 Mbps AP2 AVG = 400 Mbps
Test 5: 80 & 160 MHz Networks - 80 MHz to Ch 40
This test is essentially the same as Test 3, but with the NETGEAR set to 160 MHz wide channel.
80 MHz & 160 MHz networks - AP1 Ch 40 - Downlink
The results are eerily similar to Test 3, but more pronounced. The ASUS network using 80 MHz wide channels is clearly struggling throughout the test and again starts scanning for a new network after its throughput essentially drops to zero for around 10 seconds. Pal telemetry shows the Pal STA does reassociate a few seconds later, but that's too much of an interruption for iperf3, which doesn't resume traffic.
The uplink test shows much more even throughput sharing for much of the run than Test 3 (~5% difference). The test once again ends early, but only slightly. Pal telemetry showed no problem with association, but something caused iperf3 to disconnect a bit early.
Conclusion: The effect of a neighboring 160 MHz wide channel network appears to be no worse than an 80 MHz wide channel network.
80 MHz & 160 MHz networks - AP1 Ch 40 - Uplink
AP1 AVG= 333 Mbps AP2 AVG = 313 Mbps
Test 6: 80 & 160 MHz Networks, Intel AC 9260 STA - Both Ch 36
As noted earlier, pickin's are very slim if you're looking for 802.11ac devices that support 160 MHz wide channels. Since it's possible there is some optimization that could occur between the Qualcomm-based NETGEAR R7800 and Qualcomm-based octoScope Pal device, I decided to run the same tests using an Intel AC 9260.
I wasn't able to get the card to be recognized in a Lenovo M600 Tiny Desktop running Windows 10. But was able to get it running in a Dell XPS13 9350 running Windows 10. The XPS13 was located a few feet from both routers and ran an iperf3 server endpoint. The Intel driver version used was 220.127.116.11.
I jumped right to testing the AC 9260 in 160 MHz bandwidth mode, with both routers set to channel 36. As a reminder, AP1 is the network with an ASUS RT-AC86U and Pal 5 set to 80 MHz channel bandwidth and AP2 is the NETGEAR R7800, now with an Intel AC 9260 STA.
The first test is the same as Test 4, except it uses the Intel STA instead of an octoScope Pal as the 160 MHz channel bandwidth STA.
80 (Pal) & 160 (Intel) MHz networks - Both Ch 36 - Downlink
AP1 AVG= 400 Mbps AP2 AVG = 162 Mbps
I didn't expect to see the ASUS-based 80 MHz channel network outdo the NETGEAR/Intel WLAN, but that's what happened. I showing the better of two runs made. In the other run, the two networks wrassled even more at the start, with the 80 MHz network again coming out on top. The 160 MHz channel network had 60% lower average throughput than the standard 80 MHz wide network.
Uplink results were even more surprising. Pal telemetry for the 80 MHz network showed no scanning or breaks in association. But something happened to take down the iperf3 stream, which eventually killed the test.
Conclusion: The Intel AC 9260 did not fare as well in this test as the Qualcomm-based Pal. Something is very wrong on uplink.
80 (Pal) & 160 (Intel) MHz networks - Both Ch 36 - Uplink
Test 7: 80 & 160 MHz Networks, Intel AC 9260 STA - 80 MHz to Ch 40
The next tests repeat the Test 5 setup, but again with the Intel STA.
80 (Pal) & 160 (Intel) MHz networks - AP1 Ch 40 - Downlink
AP1 AVG= 400 Mbps AP2 AVG = 95 Mbps
Once again, the standard 11ac 80 MHz channel network cruised along at its 400 Mbps top throttled throughput, while the 160 MHz network hugged the 100 Mbps line, coming in with an average throughput almost 80% lower.
The uplink test ran a little longer than when both networks used the same primary channel (36).
Conclusion: Once again, something seems seriously wrong with the way the Intel AC 9260 STA and NETGEAR R7800 interact.
80 (Pal) & 160 (Intel) MHz networks - AP1 Ch 40 - Uplink
Test 8: Intel alone, 160 MHz channel
I ran just the Intel AC 9260 and NETGEAR R7800 in 160 MHz channel mode to see if that provided any clues to the Test 6 and 7 behavior. Channel was set to 36, and iperf3 was set to use four TCP/IP streams with no bandwidth caps. Here's the result of four downlink test runs...
Intel AC 9260 - 160 MHz B/W - Downlink
Run1 AVG= 402 Mbps Run2 AVG = 941 Mbps Run3 AVG = 941 Mbps Run4 AVG = 926 Mbps
...and four uplink. All these tests were run in a 15 minute period with no other active in-range 5 GHz networks.
Two of the four downlink runs ran at an average 1 Gbps Ethernet link rate of 941 Mbps, one stumbled a bit near the start and one didn't do well at all.
Intel AC 9260 - 160 MHz B/W - Uplink
Run1 AVG= 382 Mbps Run2 AVG = 214 Mbps Run3 AVG = 610 Mbps Run4 AVG = 605 Mbps
For uplink, we again see two of the four runs do ok, but the other two, not so much.
While this was an interesting and worthwhile exercise, it provides no clues to why the 160 MHz network using the Intel AC 9260 produced significantly lower throughput in the 80/160 neighboring network tests.
It's easy to get lost in the data. So here's a handy table of the results and conclusions for each test.
|Test||Downlink Throughput||Uplink Throughput||Conclusion|
|Test 1: Maximum Throughput - 160 vs. 80||- 160 MHz avg. = 943 Mbps
- 80 MHz avg. = 682 Mbps
|- 160 MHz avg. = 707 Mbps
- 80 MHz avg. = 677 Mbps
|Steady throughput, both directions, both networks|
|Test 2: 80 MHz - Both Channel 36||- ~20% avg. throughput difference
- AP1 avg. = 254 Mbps
- AP2 avg. = 348 Mbps
|- ~40% avg. throughput difference
- AP1 avg. = 244 Mbps
- AP2 avg. = 398 Mbps
|Even for two AC networks, bandwidth may not be shared equally.|
|Test 3: 80 MHz - AP1 to Ch 40||- Disconnect on one network during test||- AP1 avg. = 259 Mbps
- AP2 avg. = 397 Mbps
|Normal (80 MHz wide channels) neighboring 11ac networks can significantly affect each other.|
|Test 4: 80 & 160 MHz Networks - Both Ch 36||- AP1 avg. = 195 Mbps
- AP2 avg. = 344 Mbps
|- AP1 avg. = 252 Mbps
- AP2 avg. = 400 Mbps
|160 MHz wide channels appear to have the same effect on a neighboring network using 80 MHz channels as a neighboring network using 80 MHz wide channels.|
|Test 5: 80 & 160 MHz Networks - 80 MHz to Ch 40||- Disconnect on one network during test||- AP1 avg. = 333 Mbps
- AP2 avg. = 313 Mbps
|The effect of a neighboring 160 MHz wide channel network appears to be no worse than an 80 MHz wide channel network.|
|Test 6: 80 & 160 MHz Networks,
Intel AC 9260 STA - Both Ch 36
|- AP1 avg.= 400 Mbps
- AP2 avg. = 162 Mbps
|- Disconnect on one network during test||The Intel AC 9260 did not fare as well in this test as the Qualcomm-based Pal. Something is very wrong on uplink.|
|Test 7: 80 & 160 MHz Networks,
Intel AC 9260 STA - 80 MHz to Ch 40
|- AP1 avg. = 400 Mbps
- AP2 avg. = 95 Mbps
|- Disconnect on one network during test||Once again, something seems seriously wrong with the way the Intel AC 9260 STA and NETGEAR R7800 interact.|
|Test 8: Intel alone, 160 MHz channel||- Run1 avg. = 402 Mbps
- Run2 avg. = 941 Mbps
- Run3 avg. = 941 Mbps
- Run4 avg. = 926 Mbps
|- Run1 avg. = 382 Mbps
- Run2 avg. = 214 Mbps
- Run3 avg. = 610 Mbps
- Run4 avg. = 605 Mbps
|- Inconsistent throughput run-to-run.
- No indication of behavior seen in Tests 6 & 7
Table 2: Test conclusion summary
My data set is admittedly small. But I tend to think that if I can't see an advertised behavior in controlled conditions and with careful testing, then the chance of a typical user seeing the behavior is low.
So my basic takeaway is that an 802.11ac network using 160 MHz channel bandwidth parked next door could have an adverse effect on your wireless network. But no more or less than a regular 11ac network using 80 MHz channels.
And if that neighbor is using an Intel AC 9260—and they likely are since it's the only 11ac device that supports 160 MHz channels—your network might be more likely to make them unhappy than vice versa.
Of course, all this will probably change when we see 11ax networks using 160 MHz channels. So I'll get to repeat this exercise then.