topic Re: Low data rate in 5ghz netwrork in Aerohive Migrated Content

Low data rate in 5ghz netwrork

Yarael — Sun, 12 Dec 2021 12:28:57 GMT

Hi,

I recently modify my network to a full 802.11ac 5Ghz network and I can’t have more than 175Mb up and down (test on some AP’s alone, one device, nobody else).

have you an idea to resolve this ?
I have a 1gbps fiber connexion (up/down)

AP’s in my network are AP 130 230 550 1100

Re: Low data rate in 5ghz netwrork

Hans — Mon, 13 Dec 2021 09:48:41 GMT

Florian

Some questions:
- what are the WiFi specifications of the client (2x2:2, 3x3:3,...)?
- what is the channelwidth of the SSID you are using?

Re: Low data rate in 5ghz netwrork

Yarael — Mon, 13 Dec 2021 11:31:42 GMT

I'm using iPhone 13 Pro, iPad Pro M1, iMac M1, to run my test (MIMO 2x2 I think) with 40Mhz channel.

Re: Low data rate in 5ghz netwrork

Hans — Tue, 14 Dec 2021 10:04:37 GMT

Florian
I you are using a 2x2:2 device with 40Mhz channels and 802.11ac PHY you can have a max datarate of about 400Mbps (if the SNR is very good). datarates can be very volatile and are set on a per-frame basis. In reality is the 175Mbps real throughput not so strange because a lot of the airtime is used by the overhead of management and control traffic (datarates are not equal as throughput). Another sidenote, you don't share the airtime per AP, you share the airtime with every other device (clients or AP's) in 'listening-distance' (and this can be further then you think). You have to execute a spectrum analysis to check the channel utilization (wifi and non-wifi interference) to be sure there is no other device on the spectrum. Hope this could help.

Re: Low data rate in 5ghz netwrork

Yarael — Tue, 14 Dec 2021 15:02:12 GMT

I disagree with you, in other site, I'm able to have 800Mbps in 40Mhz with the same device.
When I test, the AP is alone, with no interference.

I really think there is a problem in my configuration that reduce the data rate, maybe background scanning, safety net or backhaul failover... I don't know 😞

Re: Low data rate in 5ghz netwrork

Hans — Tue, 14 Dec 2021 15:16:29 GMT

Hi Florion

if you are using a 2x2:2 device in a 40Mhz channel with the 802.11ac PHY the max is 400Mbps datarate, you may disagree however it's WiFi science ;), you can check the datarates table on this http://mcsindex.com. You need at least 80Mhz channels in this setup to get 800Mbps datarates (not the same as throughput).
However, there could be a lot of reasons why WiFi is not performing (interference, driver issues, congestion,...).

Re: Low data rate in 5ghz netwrork

Yarael — Tue, 14 Dec 2021 15:29:40 GMT

Sorry, exact in 2x2:2
So why I can have 800Mbps, iPhone 13 Pro is a 2x2 MIMO device ?

And if the max is 400Mbps, I want this lol.