[hyperfrog]

Hello,

This is my first post. I set up a WDS consisting of three identical routers (D-Link DIR-825 B1). They all have been flashed with "DD-WRT v3.0-r44467 std (09/24/20)". There is one WDS AP and two WDS stations. Each station has a virtual interface using the same SSID, shared key and security type (WPA2 personal/AES) as the main AP.

All three routers (AP and stations) are configured to use the 2.4GHz radio (Ath0), "NG-Mixed" mode and "HT40" width.

Everything is working fine save for the connection speed of any device that connects to the virtual interface of a station. Those devices always show up as "LEGACY2.5" in the wireless nodes, and the actual speed never exceeds 54Mbps.

The "funny" thing is I get better speeds (up to 150Mbps) when using HT20. However, this is not enough, and I really want to get speeds up to 300Mbps.

What am I doing wrong?

Thank you.

[egc]

The display as legacy2.5 is resolved in the next build 44483.

Maybe that also resolves your problem but not sure about that.

As you are using the same radio for back haul and AP you are effectively halving the bandwidth, theoretically 300 Mb is possible, two stream with 40 MHz channel width.
As this is halved you get 150 Mb, but in real life expect something like 70-90 Mb/s I think.

[hyperfrog]

Is it possible to use the 5GHz radio for backhaul and the 2.5GHz radio for AP? I followed the guide at https://wiki.dd-wrt.com/wiki/index.php/WDS_Linked_router_network and I was under the impression that I should use one radio only.

I know the actual speed gets halved. However, my devices are connecting at 54Mbps max when using HT40 vs 150Mbps max when using HT20, so something's obviously wrong.

[egc]

I have no experience with WDS (I connect my routers with cable or powerline adapters ) but I think they mean use only one radio as back haul.

What you describe seems the superior solution, use one radio as back haul and the other as AP.

It is possible that clients only connect at G (54 Mb/s) depending on settings but you have to wait for our Wifi experts to chime in, in the mean time upgrade to the latest 44483 build.

[eibgrad]

FYI. Having HT20 result in better performance than HT40 is NOT necessarily an indication of an error. It depends on the amount of increased interference you encounter when choosing a wider channel width. IOW, a wider channel width only helps to the extent that the breadth of that channel is free of interference. But if it's NOT, then things could actually get worse than if you used a narrower channel width. If that wasn't the case, there wouldn't even be a reason to offer anything other than the widest possible channel width.

[gin-n-tonic]

Yes, that can work.

I have two WNDR3700v4 (r44340) connected with WDS using ath1 (5 GHz) and Wide HT40 as the backhaul and see 300 Mbit/sec on the Wireless Status page. Channel setting is 157,lower (157 + 153).

2.4GHz radio is disabled on the Host (WDS AP). Client (WDS Station) uses the 2.4GHz radio (Full 20 MHz) for both wireless AP and a VAP for guest access. (Not sure I got all the terminology correct...)

Connection is robust and works great.

[hyperfrog]

@gin-n-tonic, any reason why you're using 20MHz (full) width on the 2.4Ghz radio instead of 40MHz (wide)?

[gin-n-tonic]

I am no expert. I use the settings recommended in the Forum Sticky by msoengineer. The why's behind these settings are explained in the QCA Wiki.

When I set it up and added a Roku, I did play around with the channel width but didn't notice much difference, so just went back to the recommendation. Again, see the Wiki for likely reasons why I did not see a change.

I also live in a fairly congested area (Los Angeles) so a 20MHz window will keep my neighbors happier! (maybe)

[hyperfrog]

Upgrading to r44483 seems to have solved my issue. HT40 is working again. I wish to thank everyone for their input.

[hyperfrog]

As a matter of fact, the problem was not solved by upgrading to the latest version. I still had "LEGACY" connections only on the VAPs with 54Mbps at most.

I solved my problem by enabling the "WMM Support" option in the VAPs' advanced wireless settings. Apparently, this is mandatory for proper N operation, but the option is disabled by default.

[gin-n-tonic]

Mine has WMM Support Enabled. The QCA Settings Wiki says that is the default, but it has been so long since I have done a reset, I have no idea what the current default setting is. I can confirm that disabling WMM Support slows the connections.

[msoengineer]