Best AP configuration for Netgear D7800

I have a Netgear D7800 and I want to configure it as (dumb) AP in OpenWRT.
My plan is to connect the AP to a managed switch (supports VLAN and Link Aggregation) and the switch to a router.
The picture shows the D7800 RJ45 interface capabilities.

How should I configure the AP to get the best in terms of throughput? Can I take any advantage of the two eth interfaces, somehow? If I bridge the WLANs to eth0 and eth1, can I use either of the two RJ45 port to connect my AP to the switch? Is link aggregation possible? Any suggestion or hints would be highly appreciated!

Thank you

Link aggregation isn't likely going to help you unless your radio is truly saturating a 1G link (this is possible, but unlikely in most situations).

Are you confident that your 1G link is actually being saturated (i.e. >940Mbs of actual traffic on the link at peak capacity)?

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Hi! Actually, I still need to setup my network. I am planning it. I am also sure it will be hard to saturate the 1 Gbps, but I was wondering whether link aggregation is possible and how to achieve it. Alternatively, what could be a reasonable configuration for eth0 and eth1? In my current configuration, the D7800 is a router / AP and eth0 goes to LAN1-4, whereas eth1 to WAN. When the D7800 will be just an AP, what do you suggest to do?

Creating a LAG is theoretically possible, but I am not the one who can help as I have no experience with this. I do know it makes things considerably more complex, and there is likely to be little-to-no gain in your situation.

Instead of a LAG? well, whatever you want/need them to do... normally one would be an uplink and the rest of the ports would be switched downlinks. But I'm not really sure what you're asking (if not a LAG).

In theory, yes - it's possible…

…but, ipq806x does not have the processing power to stitch the traffic back together at full line speed (maybe ~500 MBit/s, 650 MBit/s if you're lucky) - and the 802.11ac wireless won't get that over the air (especially not with the typical 2x2 clients) anyways, so why bother?
Really, save yourself the trouble, it will not help - on the contrary. LAG or no aggregation is not the bottleneck here, 802.11ac and the SOC's internal performance are.

Just as a rule of thumb (80 MHz channel width, 2x2 client, 5 GHz, same room):

  • 802.11ac: 250-400 MBit/s (ipq8064/ qca9980 tops out around 300-350 MBit/s)
  • 802.11ax: 700-800 MBit/s.

My final thought on this is as follows:

  • It has been pretty well established (espeically with @slh's info), that you will likely not get any performance gains whatsoever and may end up with reduced performance instead.
  • But, if you want to approach this as an academic exercise, then it might be worth doing. But I'd recommend doing it only for the educational aspects so you can learn new things, but then revert back because the performance may actually be lower with a LAG than without.
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@slh @psherman Thank you very much for your thoughts.
So, if my D7800 will work as a simple AP, then this would be a good starting point.
WAN and LAN are not meaningful anymore. I will just connect one of the switched ports or the former "WAN" port to the router and that's it.

By the way does it make sense to talk about upstream and downstream for an AP?

In the default configuration of the D7800, one "CPU" takes care of the traffic between from/to the LAN ports, the second one handles the traffic from/to the WAN.

Yes. In fact, it makes sense to use these terms for most networks and network devices. Upstream of your AP would be things like a nework switch (if applicable) and your router (upstream of the router is the modem/ONT/ISP connection, etc.). Downstream of your AP will be the clients (sta mode devices).

The CPU isn't really involved when using a device as a dumb AP.. with a few exceptions, the CPU is generally only involved when you are actually routing traffic (so the routing engine + firewall).

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