Wireless Access

why are my iap devices only at a fraction of wifi router speed?

I have noticed that my wifi router (i.e., modem/router/wifi equipment provided by ISP) offers full speed of the ISP's offered bandwidth plan.  Unfortunately, after optimizing wifi settings, the wifi performance of my iap's (iap205 and iap207 and iap275) do NOT match wifi router speeds...

on my iap's wifi bandwidth seems to be cut in half or more.  however, when i connect to router wifi, the speed is at 100% speed offered by isp.

I went ahead and purchased the TP-Link Deco M5 to test with ethernet backhaul (setup same way as my iap's).  the Deco M5 matched the speedtest of the router wifi's speedtest.

in a nutshell:

wifi router: 215Mbps

deco m5 ap: ~205-210Mbps

iap: 135Mbps

is there a solution to this??  I keep reading that wifi is half duplex and that's supposed to explain the ~50% in bandwidth, but that doesn't explain how a prosumer ap like tp-link (deco m5) or a wifi router would be at or near 100% of the isp's bandwidth.

NOTE:

• even without content filters, security options (ids), arp filter enabled, AND standing 10ft from iap to test, the speed at best is 135Mbps
• wired port to iap is full speed - no bottleneck there

• Build Time:	2020-05-01 01:18:58 UTC (build 75343) by p4build
  Version:	6.5.4.17

why are my iap devices only at a fraction of wifi router speed?

I've noticed that this seems to be a limitation of iap 200 series at least.  does anyone else have this issue?

A couple of things would be good to know:

- Band and channel used

- Bandwidth setting (20/40/80)

- Client device capabilities (11n/ac, MIMO)

Are those all the same for the APs you're testing with?

A couple of things would be good to know:

- Band and channel used --> 5GHz (36) pretty much uncrowded bands in the 5g space since there are not too many devices around right now.

- Bandwidth setting (20/40/80) --> 20, 40, 80... but 80 support is disabled

- Client device capabilities (11n/ac, MIMO) --> connected w/11ac... how do i find out about MIMO on client? regardless they all were tested one after the other...

Are those all the same for the APs you're testing with? --> yes

VHT40 with 2x2 MIMO gives a peak over-the-air datarate of 400Mbps, and you should expect 250Mbps or so peak TCP throughput with a single client device. 135Mbps is definitely too low. Sure you're not operating with 20MHz channels?

i am connecting on 20mhz channels when i get those results... but these are the only channels available to me:

Try setting the channel to 36+ (40MHz) or 36E (80MHz).

Also, change "80MHz support" to "enabled"

In the valid channels, the channels with the + at the end of them are 40mhz channels, and the ones with E at the end are 80mhz channels. Looks like you do have them. I would also suggest changing wide channel bands to 5ghz only, not All.

Have you tried turning off 20mhz channels? If the AP is using 40mhz channels you should see 36+ with the + meaning its running as 40mhz. 

It doesn't look like the 40mhz channels are available to me... i guess they're restricted?

i'm now looking at this as a guide:

I then enabled 80mhz channel and am using 149:

Is this the limitation of the iap207 (200 series)?  the iap275 is not any better despite an ethernet connection.  I looked up documentation, but could not find any way to test the speed of the wired connection thru the UI.  Is there any way to tweak the port settings to optimize for speed?

I'm out of ideas

thank you for your guidance.  After making all the changes to keep the channel list to 40mhz and 80mhz for 5ghz band:

and connecting on 40mhz (and 80mhz) channels tested for each... this is connecting on 40mhz channel:

the speed hasn't improved beyond 140-145Mbps... slight improvement, but it seems like the bottleneck is at the ethernet connection of the iap (???).  HOWEVER, the ethernet port on the switch the iap is connected to tests out to full speed (200+Mbps)... this is the same for all iap-207's that i have used (5 different ones).

are you getting near wifi router speeds when you connect direct? this seems like the limitation of the iap device?  I understand that it would be half speed for iap to iap w/a wifi backhaul, but shouldn't be with a wired backhaul to router, right?

what am i missing here?

thank you so far for all the help you've given.  i appreciate your feedback!