Dell Wireless 1820A & AP230, only connect at 400Mbps

[sebus]

Replaced (same physical place, same wifi in laptop)

Zyxel NWA1123-ACv2 with AP230

On 5Ghz connection speed dropped from 768Mbps to only 400Mbps (that is HALF)

Not something I expected.

Played with all the settings available in Connect, no difference, cannot make it nowhere near the same speed.

Anybody has any ideas?

Thanks

sebus

[sebus]

Zyxel config is:

Dell 1820A connection to Zyxel

[sebus]

It is not client decision if the driver has no such option!

Client will go for 2.4 because that is easier.

Only way to get it using 5Ghz is to have in config:

radio profile uknh_radio_ng_ng0 band-steering enable
radio profile uknh_radio_ng_ng0 band-steering mode force-5g

which works well and makes the client connect to 5Ghz (as show above - Network band:    5 GHz)

So there is no issue where client connects!

I have ofcourse tested also with differently named SSID for 5Ghz (getting exactly the same results = 400Mbps)

Dell 1820A connection to AP230

But the whole point of this exercise was to NOT have separate SSIDs, but a single blanket one that covers everywhere. Which is fine, apart from the speed of connection

AP230 can do 1.3 Gbps in the 5 GHz 802.11ac mode

[StephanH]

If you the client uses 2.4 or 5 Ghz is a client decision, not the decision of the AP (all solutions to force a client to sepcific frequency from the AP side is vendor proprietary). The easiest way to force a client to 2.4 or 5 Ghz is to use different SSIDs for 2.4 und 5 Ghz.

This is a good approch to test the speed on 5 Ghz.

[sebus]

Using 80MHz configured on AP230 radio profile, I cannot connect at all to the 5Ghz network (get connected to 2.4Ghz only)

Dropping to 40MHz I get the 400Mbps

SSID:    *************
Protocol:    802.11ac
Security type:    WPA2-Personal
Network band:    5 GHz
Network channel:    44
Link-local IPv6 address:    fe80::ac24:f0af:755a:a0b9%11
IPv4 address:    192.168.88.98
Manufacturer:    Broadcom
Description:    Dell Wireless 1820A 802.11ac
Driver version:    1.555.0.0
Physical address (MAC):    30-52-CB-**-**-**
 

Name:    Wi-Fi
Description:    Dell Wireless 1820A 802.11ac
Physical address (MAC):    30:52:cb:**:**:**
Status:    Operational
Maximum transmission unit:    1500
Link speed (Receive/Transmit):    144/400 (Mbps)
DHCP enabled:    Yes
 

The latest Broadcom driver for this card 1.555.0.0 (from 26/11/2015) does not have any configurable settings for 2x2 MIMO (and not even a setting for Prefer 5Ghz, hence I needed to do it in CLI of the AP)

Yet with Zyxel it was working oob at full expected speed

[StephanH]

Hello Sebus,

768Mbps to 400Mbps looks a littebit like one AP uses 80MHz and the other 40MHz wide channels. I assume that the client supports 2x2 MIMO with 802.11ac and that this is configured in the driver.

Im am not sure because in my opinion 768 is no speed in the MCS for VHT (802.11ac).

To be sure, the easiest way is to do a Wireshark trace in the air and check the settings used in the packets.