I pay for 2.5Gbps symmetric fiber through AT&T.

When testing my speed directly from the AT&T BGW320-505 I (mostly)get the speed I pay for.

Heres a speedtest directly from the modem.

I use IP Passthrough so the WAN IP goes directly to the ER8411

While connected to the ER8411, I get download speed bursts up to 8Gbps sometimes.

As of writing this I had a burst to 3.1Gbps download BUT ONLY 620Mbps upload

I know.. I know.. some people don't get the opportunity or have the infrastructure and this can come off as inconsiderate to the people who don't get city/metro fiber in their area, but I do and the upload speed is abysmal.

Here's a test from Fast(dot)com showing my download at 3.1Gbps and upload of 620Mbps.

This is the same at Speedtest as well and any other speed test that isn't tied to Fast(Verizon) or Speedtest(Ookla)

I've also tried M-Lab, Testmy(dot)net, and Speedof(dot)me and they all conclude the same thing from the ER8411

If I connect my PC to the Modem directly, and run these speed tests, they give consistent download/upload, it is strictly the ER8411 that is limiting the upload.

Now the problem, the upload; Why is the upload not even hitting 1Gbps?

I have a 10Gbps SFP+ module installed(10Gtek ASF-10G-T), and it's obviously getting download speeds fine.

I've seen other posts(on Reddit) about this as well but opposite, where there upload is perfectly fine, but their download is not up to par with what is being paid for.

Is there a particular SFP+ module that is supported?

I've tried speed tests on multiple devices that have different ethernet cards ranging from 2.5Gb, 5Gb, and 10Gbps endpoint ethernet and all of them are between 300-600Mbps upload. What's the deal?

I've tinkered with settings thinking that maybe something being turned off or on was the problem, but nothing has solved this yet.

Someone, anyone, can I get help or an explanation? Do I need to buy a TP-Link module, such as the TL-SM5310-T?